WO2011112927A1

WO2011112927A1 - Three-point spindle-supported floating abrasive platen

Info

Publication number: WO2011112927A1
Application number: PCT/US2011/028088
Authority: WO
Inventors: Wayne O. Duescher
Original assignee: Duescher Wayne O
Priority date: 2010-03-12
Filing date: 2011-03-11
Publication date: 2011-09-15
Also published as: EP2544855A1; US20110223838A1; US8500515B2; US20110294405A1; US8328600B2

Abstract

A method and apparatus for releasably attaching flexible abrasive disks to a flat- surfaced platen that floats in three-point abrading contact with three rigid flat-surfaced rotatable fixed-position workpiece spindles that are mounted on a flat surface of an abrading machine base where the spindle surfaces are in a common plane. The three spindles are positioned to form a three-point triangle of platen supports where the rotational-centers of each of the spindles are positioned at the center of the annular width of the platen abrading surface. Flat surfaced workpieces are attached to the spindles and the rotating floating-platen abrasive surface contacts all three rotating workpieces to perform single-sided abrading. The platen abrasive surface can be re-flattened by attaching equal-thickness abrasive disks to the three spindles that are rotated while in abrading contact with the rotating platen abrasive. There is no wear of the abrasive-disk protected platen surface.

Description

THREE-POINT SPINDLE- SUPPORTED FLOATING ABRASIVE PLATEN RELATED APPLICATION DATA

This Application claims priority from US Patent Application Serial No.

12/661,212, filed March 12, 2010, 12/799,841, filed May 3, 2010, and 12/807,802, filed September 14, 2010.

BACKGROUND OF THE INVENTION

1 Field of the Invention

The present invention relates to the field of abrasive treatment of surfaces such as grinding, polishing and lapping. In particular, the present invention relates to a high speed lapping system that provides simplicity, quality and efficiency to existing lapping technology using multiple floating platens.

Flat lapping of workpiece surfaces used to produce precision-flat and mirror smooth polished surfaces is required for many high-value parts such as semiconductor wafer and rotary seals. The accuracy of the lapping or abrading process is constantly increased as the workpiece performance, or process requirements, become more demanding. Workpiece feature tolerances for flatness accuracy, the amount of material removed, the absolute part- thickness and the smoothness of the polish become more progressively more difficult to achieve with existing abrading machines and abrading processes. In addition, it is necessary to reduce the processing costs without sacrificing performance. Also, it is highly desirable to eliminate the use of messy liquid abrasive slurries. Changing the abrading process set-up of most of the present abrading systems to accommodate different sized abrasive particles, different abrasive materials or to match abrasive disk features or the size of the abrasive disks to the workpiece sizes is typically tedious and difficult.

Fixed-Spindle-Floating-Platen System

The present invention relates to methods and devices for a single-sided lapping machine that is capable of producing ultra-thin semiconductor wafer workpieces at high abrading speeds. This is done by providing a flat surfaced granite machine base that is used for mounting three individual rigid flat-surfaced rotatable workpiece spindles.

Flexible abrasive disks having annular bands of fixed-abrasive coated raised islands are attached to a rigid flat-surfaced rotary platen. The platen annular abrading surface floats in three-point abrading contact with flat surfaced workpieces that are mounted on the three equal-spaced flat-surfaced rotatable workpiece spindles. Water coolant is used with these raised island abrasive disks.

Presently, floating abrasive platens are used in double-sided lapping and double- sided micro-grinding (flat-honing) but the abrading speeds of both of these systems are very low. The upper floating platen used with these systems are positioned in conformal contact with multiple equal-thickness workpieces that are in flat contact with the flat abrading surface of a lower rotary platen. Both the upper and lower abrasive coated platens are typically concentric with each other and they are rotated independent of each other. Often the platens are rotated in opposite directions to minimize the net abrading forces that are applied to the workpieces that are sandwiched between the flat annular abrading surfaces of the two platens.

In order to compensate for the different abrading speeds that exist at the inner and outer radii of the annular band of abrasive that is present on the rotating platens, the workpieces are rotated. The speed of the rotated workpiece reduces the too-fast platen speed at the outer periphery of the platen and increases the too-slow speed at the inner periphery when the platen and the workpiece are both rotated in the same direction.

However, if the upper abrasive platen and the lower abrasive platen are rotated in opposite directions, then rotation of the workpieces is favorable to the platen that is rotated in the same direction as the workpiece rotation and is unfavorable for the other platen that rotates in a direction that opposes the workpiece rotation direction. Here, the speed differential provided by the rotated workpiece acts against the abrading speed of the opposed rotation direction platen. Because the localized abrading speed represents the net speed difference between the workpieces and the platen, rotating them in opposite directions increases the localized abrading speeds to where it is too fast. Providing double-sided abrading where the upper and lower platens are rotated in opposed directions results over-speeding of the abrasive on one surface of a workpiece compared to an optimum abrading speed on the opposed workpiece surface.

In double-sided abrading, rotation of the workpieces is typically done with thin gear-driven planetary workholder disks that carry the individual workpieces while they are sandwiched between the two platens. Workpieces comprising semiconductor wafers are very thin so the planetary workholders must be even thinner to allow unimpeded abrading contact with both surfaces of the workpieces. The gear teeth on these thin workholder disks that are used to rotate the disks are very fragile, which prevents fast rotation of the workpieces. The resultant slow-rotation workpieces prevent fast abrading speeds of the abrasive platens. Also, because the workholder disks are fragile, the upper and lower platens are often rotated in opposite directions to minimize the net abrading forces on individual workpieces because a portion of this net workpiece abrading force is applied to the fragile disk-type workholders. It is not practical to abrade very thin workpieces with double-sided platen abrasive systems because the required very thin planetary workholder disks are so fragile.

Multiple workpieces are often abrasive slurry lapped using flat-surfaced single- sided platens that are coated with a layer of loose abrasive particles that are in a liquid mixture. Slurry lapping is very slow, and also, very messy.

The platen slurry abrasive surfaces also wear continually during the workpiece abrading action with the result that the platen abrasive surfaces become non-flat. Non-flat platen abrasive surfaces result in non-flat workpiece surfaces. These platen abrasive surfaces must be periodically reconditioned to provide flat workpieces. Conditioning rings are typically placed in abrading contact with the moving annular abrasive surface to re-establish the planar flatness of the platen annular band of abrasive.

In single-sided slurry lapping, a rigid rotating platen has a coating of abrasive in an annular band on its planar surface. Floating-type spherical-action workholder spindles hold individual workpieces in flat-surfaced abrading contact with the moving platen slurry abrasive with controlled abrading pressure.

The fixed-spindle-floating-platen abrading system has many unique features that allow it to provide flat-lapped precision-flat and smoothly-polished thin workpieces at very high abrading speeds. Here, the top flat surfaces of the individual spindles are aligned in a common plane where the flat surface of each spindle top is co-planar with each other. Each of the three rigid spindles is positioned with approximately equal spacing between them to form a triangle of spindles that provide three-point support of the rotary abrading platen. The rotational-centers of each of the spindles are positioned on the granite so that they are located at the radial center of the annular width of the precision-flat abrading platen surface. Equal-thickness flat-surfaced workpieces are attached to the flat- surfaced tops of each of the spindles. The rigid rotating floating-platen abrasive surface contacts all three rotating workpieces to perform single-sided abrading on the exposed surfaces of the workpieces. The fixed-spindle-floating platen system can be used at high abrading speeds with water cooling to produce precision-flat and mirror-smooth workpieces at very high production rates. There is no abrasive wear of the platen surface because it is protected by the attached flexible abrasive disks. Use of abrasive disks that have annular bands of abrasive coated raised islands prevents the common problem of hydroplaning of workpieces when contacting coolant water-wetted continuous-abrasive coatings. Hydroplaning of workpieces causes non-flat workpiece surfaces.

This abrading system can also be used to recondition the flat surface of the abrasive that is on the abrasive disk that is attached to the platen. A platen annular abrasive surface tends to experience uneven wear across the radial surface of the annular abrasive band after continued abrading contact with the flat surfaced workpieces. When the non-even wear of the abrasive surface becomes excessive and the abrasive can no longer provide precision-flat workpiece surfaces it must be reconditioned to re-establish its precision planar flatness. Reconditioning the platen abrasive surface can be easily accomplished with this fixed-spindle floating-platen system by attaching equal-thickness abrasive disks, or other abrasive devices such as abrasive coated conditioning rings, to the flat surfaces of the rotary spindle tops in place of the workpieces. Here, the platen annular abrasive surface reconditioning takes place by rotating the spindle abrasive disks, or conditioning rings, while they are in flat-surfaced abrading contact with the rotating platen abrasive annular band.

Also, the bare platen (no abrasive coating) annular abrading surface can be reconditioned with this fixed-spindle floating-platen system by attaching equal-thickness abrasive disks, or other abrasive devices such as abrasive coated conditioning rings, to the flat surfaces of the rotary spindle tops in place of the workpieces. Here, the platen annular abrading surface reconditioning takes place by rotating the spindle abrasive disks, or conditioning rings, while they are in flat-surfaced abrading contact with the rotating platen annular abrading surface. Most conventional platen abrading surfaces have original- condition flatness tolerances of 0.0001 inches (3 microns) that typically wear down into a non-flat condition during abrading operations to approximately 0.0006 inches (15 microns) before they are reconditioned to re-establish the original flatness variation of 0.0001 inches (3 microns).

Furthermore, the system can be used to recondition the flat surfaces of the spindles or the surfaces of workpiece carrier devices that are attached to the spindle tops by bringing an abrasive coated floating platen into abrading contact with the bare spindle tops, or into contact with the workpiece carrier devices that are attached to the spindle tops, while both the spindles and the platen are rotated. This fixed- spindle-floating-platen system is particularly suited for flat-lapping large diameter semiconductor wafers. High-value large-sized workpieces such as 12 inch diameter (300 mm) semiconductor wafers can be attached with vacuum or by other means to ultra-precise flat-surfaced air bearing spindles for precision lapping of the wafers. Commercially available abrading machine components can be easily assembled to construct these lapper machines. Ultra-precise 12 inch diameter air bearing spindles can provide flat rotary mounting surfaces for flat wafer workpieces. These spindles typically provide spindle top flatness accuracy of 5 millionths of an inches (or less, if desired) during rotation. They are also very stiff for resisting abrading load deflections and can support loads of 900 lbs. A typical air bearing spindle having a stiffness of 4,000,000 lbs/inch is more resistant to deflections from abrading forces than a mechanical spindle having steel roller bearings.

The thicknesses of the workpieces can be measured during the abrading or lapping procedure by the use of laser, or other, measurement devices that can measure the workpiece thicknesses. These workpiece thickness measurements can be made by direct workpiece exposed-edge side measurements. They also can be made indirectly by measuring the location of the bottom position of the moving abrasive surface that makes contact with the workpiece surfaces as the abrasive surface location measurement is related to an established reference position.

Air bearing workpiece spindles can be replaced or extra units added as needed.

These air bearing spindles are preferred because of their precision flatness of the spindle surfaces at all abrading speeds and their friction-free rotation. Commercial 12 inch (300 mm) diameter air bearing spindles that are suitable for high speed flat lapping are available from Nelson Air Corp, Milford, NH. Air bearing spindles are preferred for high speed flat lapping but suitable rotary flat-surfaced spindles having conventional roller bearings can also be used.

Thick-section granite bases that have the required surface flatness accuracy, structural stiffness and dimensional stability to support these heavy air bearing spindles without distortion are also commercially available from numerous sources. Fluid passageways can be provided within the granite bases to allow the circulation of heat transfer fluids that thermally stabilize the bases. This machine base temperature control system provides long-term dimensional stability of the precision-flat granite bases and isolates them from changes in the ambient temperature changes in a production facility. Floating platens having precision-flat planar annular abrading surfaces can also be fabricated or readily purchased.

The flexible abrasive disks that are attached to the platen annular abrading surfaces typically have annular bands of fixed-abrasive coated rigid raised-island structures. There is insignificant elastic distortion of the individual raised islands through the thickness of the raised island structures or elastic distortion of the complete thickness of the raised island abrasive disks when they are subjected to typical abrading pressures. These abrasive disks must also be precisely uniform in thickness across the full annular abrading surface of the disk. This is necessary to assure that uniform abrading takes place over the full flat surface of the workpieces that are attached onto the top surfaces of each of the three spindles. The term "precisely" as used herein refers to within +5 wavelengths planarity and within +0.01 degrees of perpendicular or parallel, and precisely coplanar means within +0.01 degrees of parallel, thickness or flatness variations of less than 0.0001 inches (3 microns) and with a standard deviation between planes that does not exceed +20 microns.

During an abrading or lapping procedure, both the workpieces and the abrasive platens are rotated simultaneously. Once a floating platen "assumes" a position as it rests conformably upon workpieces attached to the spindle tops and the platen is supported by the three spindles, the planar abrasive surface of the platen retains this nominal platen alignment even as the floating platen is rotated. The three-point spindles are located with approximately equal spacing between them circumferentially around the platen and their rotational centers are in alignment with the radial centerline of the platen annular abrading surface. A controlled abrading pressure is applied by the abrasive platen to the equal- thickness workpieces that are attached to the three rotary workpiece spindles. Due to the evenly-spaced three-point support of the floating platen, the equal-sized workpieces attached to the spindle tops experience the same shared platen-imposed abrading forces and abrading pressures. Here, precision-flat and smoothly polished semiconductor wafer surfaces can be simultaneously produced at all three spindle stations by the fixed- spindle- floating platen abrading system.

Because the floating-platen and fixed-spindle abrading system is a single-sided process, very thin workpieces such as semiconductor wafers or flat-surfaced solar panels can be attached to the rotatable spindle tops by vacuum or other attachment means. To provide abrading of the opposite side of a workpiece, it is removed from the spindle, flipped over and abraded with the floating platen. This is a simple two-step procedure. Here, the rotating spindles provide a workpiece surface that is precisely co-planar with the opposed workpiece surface.

The spindles and the platens can be rotated at very high speeds, particularly with the use of precision-thickness raised-island abrasive disks. These abrading speeds can exceed 10,000 surface feet per minute (SFPM) or 3,048 surface meters per minute. The abrading pressures used here for flat lapping are very low because of the extraordinary high material removal rates of superabrasives (including diamond or cubic boron nitride (CBN)) when operated at very high abrading speeds. The abrading pressures are often less than 1 pound per square inch (0.07 kilogram per square cm) which is a small fraction of the abrading pressures commonly used in abrading. Flat honing (micro-grinding) uses extremely high abrading pressures which can result in substantial sub-surface damage of high value workpieces. The low abrading pressures used here result in highly desired low subsurface damage. In addition, low abrading pressures result in lapper machines that have considerably less weight and bulk than conventional abrading machines.

Use of a platen vacuum disk attachment system allows quick set-up changes where abrasive disks having different sizes of abrasive particles and different types of abrasive material can be quickly attached to the flat platen annular abrading surfaces. Changing the sized of the abrasive particles on all of the other abrading systems is slow and tedious. Also, the use of messy loose-abrasive slurries is avoided by using the fixed-abrasive disks.

A minimum of three evenly-spaced spindles are used to obtain the three-point support of the upper floating platen by contacting the spaced workpieces. However, additional spindles can be mounted between any two of the three spindles that form three- point support of the floating platen. Here all of the workpieces attached to the spindle- tops are in mutual flat abrading contact with the rotating platen abrasive.

Semiconductor wafers or other workpieces can be processed with a fully automated easy-to-operate process that is especially easy to incorporate into the fixed- spindle floating-platen lapping or abrading system. Here, individual semiconductor wafers, workpieces or workpiece carriers can be changed on all three spindles with a robotic arm extending through a convenient gap-opening between two adjacent stand- alone workpiece rotary spindles. Flexible abrasive disks can be changed on the platen by using a robotic arm extending through a convenient gap-opening between two adjacent stand-alone workpiece rotary spindles.

This three-point fixed- spindle-floating-platen abrading system can also be used for chemical mechanical planarization (CMP) abrading of semiconductor wafers that are attached to the spindle-tops by using liquid abrasive slurry and chemical mixtures with resilient backed pads that are attached to the floating platen. The system can also be used with CMP-type fixed-abrasive shallow-island abrasive disks that are backed with resilient support pads. These abrasive shallow-islands can either be mold-formed on the surface of flexible backings or the abrasive shallow-islands can be coated on the backings using gravure-type coating techniques.

This three-point fixed- spindle-floating-platen abrading system can also be used for slurry lapping of the workpieces that are attached to the rotary spindle-tops by applying a coating of liquid abrasive slurry to the abrading surface of the platen. Also, a flat-surfaced annular metal or other material disk can be attached to the platen abrading surface and a coating of liquid abrasive slurry can be applied to the flat abrading surface of the attached annular disk.

The system has the capability to resist large mechanical abrading forces that can be present with abrading processes while maintaining unprecedented rotatable workpiece spindle tops flatness accuracies and minimum mechanical flatness out-of-planar variations, even at very high abrading speeds. There is no abrasive wear of the flat surfaces of the spindle tops because the workpieces are firmly attached to the spindle tops and there is no motion of the workpieces relative to the spindle tops. Rotary abrading platens are inherently robust, structurally stiff and resistant to deflections and surface flatness distortions when they are subjected to substantial abrading forces. Because the system is comprised of robust components, it has a long production usage lifetime with little maintenance even in the harsh abrading environment present with most abrading processes. Air bearing spindles are not prone to failure or degradation and provide a flexible system that is quickly adapted to different polishing processes. Drip shields can be attached to the air bearing spindles to prevent abrasive debris from contaminating the spindle.

All of the precision-flat abrading processes presently in commercial lapping use typically have very slow abrading speeds of about 5 mph (8 kph). By comparison, the high speed flat lapping system operates at or above 100 mph (160 kph). This is a speed difference ratio of 20 to 1. Increasing abrading speeds increase the material removal rates. High abrading speeds result in high workpiece production rates and large cost savings.

To provide precision-flat workpiece surfaces, it is important to maintain the required flatness of annular band of fixed-abrasive coated raised islands during the full abrading life of an abrasive disk. This is done by selecting abrasive disks where the full surface of the abrasive is contacted by the workpiece surface. This results in uniform wear-down of the abrasive.

The many techniques already developed to maintain the abrasive surface flatness are also very effective for the fixed-spindle floating-platen lapping system. The primary technique is to use the abraded workpieces themselves to keep the abrasive flat during the lapping process. Here large workpieces (or small workpieces grouped together) are also rotated as they span the radial width of the rotating annular abrasive band. Another technique uses driven planetary workholders that move workpieces in constant orbital spiral path motions across the abrasive band width. Other techniques include the periodic use of annular abrasive coated conditioning rings to abrade the non-flat surfaces of the platen abrasive or the platen body abrading surface. These conditioning rings can be rotated while remaining at stationary positions. They also can be moved around the circumference of the platen while they are rotated by planetary circulation mechanism devices. Conditioning rings have been used for years to maintain the flatness of slurry platens that utilize loose abrasive particles. These same types of conditioning rings are also used to periodically re-flatten the fixed- abrasive continuous coated platens used in micro-grinding (flat-honing).

Workpieces are often rotated at rotational speeds that are approximately equal to the rotational speeds of the platens to provide approximately equal localized abrading speeds across the full radial width of the platen abrasive when the workpiece spindles are rotated in the same rotation direction as the platens.

Unlike slurry lapping, there is no abrasive wear of raised island abrasive disk platens because only the non-abrasive flexible disk backing surface contacts the platen surface. Here, the abrasive disk is firmly attached to the platen flat annular abrading surface. Also, the precision flatness of the high speed flat lapper abrasive surfaces can be completely re-established by simply and quickly replacing an abrasive disk having a non- flat abrasive surface with another abrasive disk that has a precision-flat abrasive surface.

Vacuum is used to quickly attach flexible abrasive disks, having different sized particles, different abrasive materials and different array patterns and styles of raised islands. Each flexible disk conforms to the precision-flat platen surface provide precision- flat planar abrading surfaces. Quick lapping process set-up changes can be made to process a wide variety of workpieces having different materials and shapes with application-selected raised island abrasive disks that are optimized for them individually. Small and medium diameter disks are very light in weight and have very little bulk thickness. They can be stored or shipped flat where individual disks lay in layers in flat contact with other companion disks. Large and very large raised island fixed- abrasive disks can be rolled and stored or shipped in polymer protective tubes. Abrasive disk and floating platens can have a wide range of abrading surface diameters that range from 2 inches (5 cm) to 72 inches (183 cm) or even much greater diameters. Abrasive disks that have non-island continuous coatings of abrasive material can also be used on the fixed- spindle floating-platen abrading system

The abrasive disk quick change capability is especially desirable for laboratory lapping machines but it is also very useful for prototype lapping and for full-scale production lapping machines. This abrasive disk quick-change capability also provides a large advantage over micro-grinding (flat-honing) where it is necessary to change-out a worn heavy rigid platen or to replace it with one having different sized particles.

Changing the non-flat fixed abrasive surface of a micro-grinding (flat-honing) thick abrasive wheel can not be done quickly because it is a bolted-on integral part of the rotating platen that supports it. Often, the abrasive particle sizes are sequentially changed from coarse to medium to fine during a flat lapping or abrading operation.

Hydroplaning of workpieces occurs when smooth abrasive surfaces, having a continuous thin-coated abrasive, are in fast-moving contact with a flat workpiece surface in the presence of surface water. However, hydroplaning does not occur when interrupted- surfaces, such as abrasive coated raised islands, contact a flat water-wetted workpiece surface. An analogy to the use of raised islands in the presence of coolant water films is the use of tread lugs on auto tires which are used on rain slicked roads. Tires with lugs grip the road at high speeds while bald smooth-surfaced tires hydroplane. In the same way, the abrasive coatings of the flat-surface tops of the raised islands remain in abrading contact with water-wetted flat-surfaced workpieces, even at very high abrading speeds.

A uniform thermal expansion and contraction of air bearing spindles occurs on all of the air bearing spindles mounted on the granite or other material machine bases when each of individual spindles are mounted with the same methods on the bases. The spindles can be mounted on spindle legs attached to the bottom of the spindles or the spindles can be mounted to legs that are attached to the upper portion of the spindle bodies and the length expansion or shrinkage of all of the spindles will be the same. This insures that precision abrading can be achieved with these fixed-spindle floating-platen abrading systems. This invention references commonly assigned U.S. patents numbers 5,910,041 ; 5,967,882; 5,993,298; 6,048,254; 6,102,777; 6,120,352 ; 6,149,506; 6,607,157; 6,752,700; 6,769,969; 7,632,434 and 7,520,800, commonly assigned U.S. patent application published numbers 20100003904; 20080299875 and 20050118939 and U.S. patent application serial numbers 12/661,212, 12/799,841 and 12/807,802 and all contents of which are incorporated herein by reference.

U.S. Patent No. 7,614,939 (Tolles et al) describes a CMP polishing machine that uses flexible pads where a conditioner device is used to maintain the abrading

characteristic of the pad. Multiple CMP pad stations are used where each station has different sized abrasive particles. U.S. Patent No. 4,593,495 (Kawakami et al) describes an abrading apparatus that uses planetary workholders. U.S. Patent No. 4,918,870 (Torbert et al) describes a CMP wafer polishing apparatus where wafers are attached to wafer carriers using vacuum, wax and surface tension using wafer. U.S. Patent No.

5,205,082 (Shendon et al) describes a CMP wafer polishing apparatus that uses a floating retainer ring. U.S. Patent No. 6,506,105 (Kajiwara et al) describes a CMP wafer polishing apparatus that uses a CMP with a separate retaining ring and wafer pr3essure control to minimize over-polishing of wafer peripheral edges. U.S. Patent No. 6,371,838 (Holzapfel) describes a CMP wafer polishing apparatus that has multiple wafer heads and pad conditioners where the wafers contact a pad attached to a rotating platen. U.S. Patent No. 6,398,906 (Kobayashi et al) describes a wafer transfer and wafer polishing apparatus. U.S. Patent No. 7,357,699 (Togawa et al) describes a wafer holding and polishing apparatus and where excessive rounding and polishing of the peripheral edge of wafers occurs. U.S. Patent No. 7,276,446 (Robinson et al) describes a web-type fixed-abrasive CMP wafer polishing apparatus.

U.S. Patent No. 6,786,810 (Muilenberg et al) describes a web-type fixed-abrasive

CMP article. U.S. Patent No. 5,014,486 (Ravipati et al) and U.S. Patent No. 5,863,306 (Wei et al) describe a web-type fixed-abrasive article having shallow-islands of abrasive coated on a web backing using a rotogravure roll to deposit the abrasive islands on the web backing. U.S. Patent No. 5,314,513 (Milleret al) describes the use of ceria for abrading.

Various abrading machines and abrading processes are described in U.S. Patents 5,364,655 (Nakamura et al). 5,569,062 (Karlsrud), 5,643,067 (Katsuoka et al), 5,769,697 (Nisho), 5,800,254 (Motley et al), 5,916,009 (Izumi et al), 5,964,651 (hose), 5,975,997 (Minami, 5,989,104 (Kim et al), 6,089,959 (Nagahashi, 6,165,056 (Hayashi et al), 6,168,506 (McJunken), 6,217,433 (Herman et al), 6,439,965 (Ichino), 6,893,332 (Castor), 6,896,584 (Perlov et al), 6,899,603 (Homma et al), 6,935,013 (Markevitch et al),

7,001,251 (Doan et al), 7,008,303 (White et al), 7,014,535 (Custer et al), 7,029,380 (Horiguchi et al), 7,033,251 (Elledge), 7,044,838 (Maloney et al), 7,125,313 (Zelenski et al), 7,144,304 (Moore), 7,147,541 (Nagayama et al), 7,166,016 ( Chen), 7,250,368 (Kida et al), 7,367,867 (Boiler), 7,393,790 (Britt et al), 7,422,634 (Powell et al), 7,446,018 (Brogan et al), 7,456,106 (Koyata et al), 7,470,169 (Taniguchi et al), 7,491,342

(Kamiyama et al), 7,507,148 (Kitahashi et al), 7,527,722 (Sharan) and 7,582,221 (Netsu et al).

SUMMARY OF THE INVENTION

The presently disclosed technology includes a fixed-spindle, floating-platen system which is a new configuration of a single-sided lapping machine system. This system is capable of producing ultra- flat thin semiconductor wafer workpieces at high abrading speeds. This can be done by providing a precision-flat, rigid (e.g., synthetic, composite or granite) machine base that is used as the planar mounting surface for at least three rigid flat-surfaced rotatable workpiece spindles. Precision-thickness flexible abrasive disks are attached to a rigid flat-surfaced rotary platen that floats in three-point abrading contact with the three equal-spaced flat-surfaced rotatable workpiece spindles. These abrasive coated raised island disks have disk thickness variations of less than 0.0001 inches (3 microns) across the full annular bands of abrasive-coated raised islands to allow flat- surfaced contact with workpieces at very high abrading speeds and to assure that all of the expensive diamond abrasive particles that are coated on the island are fully utilized during the abrading process. Use of a platen vacuum disk attachment system allows quick set-up changes where different sizes of abrasive particles and different types of abrasive material can be quickly attached to the flat platen surfaces.

Water coolant is used with these raised island abrasive disks, which allows them to be used at very high abrading speeds, often in excess of 10,000 SFPM (160 km per minute). The coolant water is typically applied directly to the top surfaces of the workpieces. The applied coolant water results in abrading debris being continually flushed from the abraded surface of the workpieces. Here, when the water-carried debris falls off the spindle top surfaces it is not carried along by the platen to contaminate and scratch the adjacent high-value workpieces, a process condition that occurs in double- sided abrading and with continuous-coated abrasive disks. The fixed-spindle floating-platen flat lapping system has two primary planar references. One planar reference is the precision-flat annular abrading surface of the rotatable floating platen. The other planar reference is the precision co-planar alignment of the flat surfaces of the rotary spindle tops of the three workpiece spindles that provide three -point support of the floating platen.

Flat surfaced workpieces are attached to the spindle tops and are contacted by the abrasive coating on the platen abrading surface. Both the workpiece spindles and the abrasive coated platens are simultaneously rotated while the platen abrasive is in controlled abrading pressure contact with the exposed surfaces of the workpieces.

Workpieces are sandwiched between the spindle tops and the floating platen. This lapping process is a single-sided workpiece abrading process. The opposite surfaces of the workpieces can be lapped by removing the workpieces from the spindle tops, flipping them over, attaching them to the spindle tops and abrading the second opposed workpiece surfaces with the platen abrasive.

A granite machine base provides a dimensionally stable platform upon which the three (or more) workpiece spindles are mounted. The spindles must be mounted where their spindle tops are precisely co-planar within 0.0001 inches (3 microns) in order to successfully perform high speed flat lapping. The rotary workpiece spindles must provide rotary spindle tops that remain precisely flat at all operating speeds. Also, the spindles must be structurally stiff to avoid deflections in reaction to static or dynamic abrading forces.

Air bearing spindles are the preferred choice over roller bearing spindles for high speed flat lapping. They are extremely stiff, can be operated at very high rotational speeds and are frictionless. Because the air bearing spindles have no friction, torque feedback signal data from the internal or external spindle drive motors can be used to determine the state-of-finish of lapped workpieces. Here, as workpieces become flatter and smoother, the water wetted adhesive bonding stiction between the flat surfaced workpieces and the flat-type abrasive media increase. The relationship between the state-of-finish of the workpieces and the adhesive stiction is a very predictable characteristic and can be readily used to control or terminate the flat lapping process.

Air bearing or mechanical roller bearing workpiece spindles having equal precision heights can be mounted on precisely flat granite bases to provide a system where the flat spindle tops are precisely co-planar with each other. These precision height spindles and precision flat granite bases are more expensive than commodity type spindles and granite bases. Commodity type air bearing spindles and non-precision flat granite bases can be utilized with the use of adjustable height legs that are attached to the bodies of the spindles. The flat surfaces of the spindle tops can be aligned to be precisely co-planar within the required 0.0001 inches (3 microns) with the use of a rotating leaser beam measurement device supplied by Hamar Laser Inc. of Danbury, CT.

An alternative method that can be used to attach spindles to granite bases is to provide spherical- action mounts for each spindle. These spherical mounts allow each spindle top to be aligned to be co-planar with the other attached spindles. Workpiece spindles are attached to the rotor portion of the spherical mount that has a spherical-action rotation within a spherical base that has a matching spherical shaped contacting area. The spherical-action base is attached to the flat surface of a granite machine base. After the spindle tops are precisely aligned to be co-planar with each other, a mechanical or adhesive-based fastener device is used to fixture or lock the spherical mount rotor to the spherical mount base. Using these spherical-action mounts, the precision aligned workpiece spindles are structurally attached to the granite base.

Another very simple technique that can be used for co-planar alignment of the spindle-tops is to use the precision-flat surface of a floating platen annular abrading surface as a physical planar reference datum for the spindle tops. Platens must have precision flat surfaces where the flatness variation is less than 0.0001 inches (nominally 3 microns) in order to successfully perform high speed flat lapping. Here, the precision-flat platen is brought into flat surfaced contact with the spindle-tops where pressurized air or a liquid can be applied through fluid passageways to form a spherical-action fluid bearing that allows the spherical rotor to freely float without friction within the spherical base. This platen surface contacting action aligns the spindle-tops with the flat platen surface. By this platen-to- spindles contacting action, the spindle tops are also aligned to be co- planar with each other. After co-planar alignment of the spindle tops, vacuum can be applied through the fluid passageways to temporarily lock the spherical rotors to the spherical bases. Then, a mechanical fastener or an adhesive -based fastener device is used to fixture or lock the spherical mount rotor to the spherical mount base. When using an adhesive rotor locking system, an adhesive can be applied in a small gap between a removable bracket that is attached to the spherical rotor and a removable bracket that is attached to the spherical base to rigidly bond the spherical rotor to the spherical base after the adhesive is solidified. If it is desired to re-align the spindle top, the removable spherical mount rotor and spherical base adhesive brackets can be discarded and replaced with new individual brackets that can be adhesively bonded together to again lock the spherical mount rotors to the respective spherical bases.

The fixed-platen floating- spindle lapping system can also be used to recondition the abrasive surface of the abrasive disk that is attached to the platen. This rotary platen annular abrasive surface tends to experience uneven wear across the radial surface of the annular abrasive band after continued abrading contact with the spindle workpieces. When the non-even wear of the abrasive surface becomes excessive and the abrasive can no longer provide precision-flat workpiece surfaces it must be reconditioned to reestablish its planar flatness.

Reconditioning the platen abrasive surface can be easily accomplished with this system by attaching equal-thickness abrasive disks to the flat surfaces of the spindles in place of the workpieces. Here, the abrasive surface reconditioning takes place by rotating the spindle abrasive disks while they are in flat-surfaced abrading contact with the rotating platen abrasive annular band.

In addition, the fixed-platen floating-spindle lapping system can also be used to recondition the platen bare (no abrasive coating) abrading surface by attaching equal- thickness abrasive disks, or other abrasive devices such as abrasive coated conditioning rings, to the flat surfaces of the rotary spindle tops in place of the workpieces. Here, the platen annular abrading surface reconditioning takes place by rotating the spindle abrasive disks, or conditioning rings, while they are in flat-surfaced abrading contact with the rotating platen annular abrading surface.

Automatic robotic devices can be added to the fixed-spindle-floating-platen system to change both the workpieces and the abrasive disks.

The fixed-platen floating- spindle lapping system has the capability to resist large mechanical abrading forces present with abrading processes with unprecedented flatness accuracies and minimum mechanical planar flatness variations. Because the system is comprised of robust components it has a long lifetime with little maintenance even in the harsh abrading environment present with most abrading processes. Air bearing spindles are not prone to failure or degradation and provide a flexible system that is quickly adapted to different polishing processes.

Platen surfaces have patterns of vacuum port holes that extend under the abrasive annular portion of an abrasive disk to assure that the disk is firmly attached to the platen surface. When an abrasive disk is attached to a flat platen surface with vacuum, the vacuum applies in excess of 10 pound per square inch (0.7 kg per square cm) hold-down clamping forces to bond the flexible abrasive disk to the platen. Because the typical abrasive disks have such a large surface area, the total vacuum clamping forces can easily exceed thousands of pounds of force which results in the flexible abrasive disk becoming an integral part of the structurally stiff and heavy platen. Use of the vacuum disk attachment system assures that each disk is in full conformal contact with the platen flat surface. Also, each individual disk can be marked so that it can be remounted in the exact same tangential position on the platen by using the vacuum attachment system. Here, a disk that is "worn-in" to compensate for the flatness variation of a given platen will recapture the unique flatness characteristics of that platen position by orienting the disk and attaching it to the platen at its original platen circumference position. This abrasive disk will not have to be "worn-in" again upon reinstallation. Expensive diamond abrasive particles are sacrificed each time it is necessary to wear-in an abrasive disk to establish a precision flatness of the disk abrasive surface. The original surface-flatness of the abrasive disk is re-established by simply mounting the previously removed abrasive disk in the same circumferential location on the platen that it had before it was removed from that same platen

BRIEF DESCRIPTION OF THE DRAWINGS

Fig. 1 is an isometric view of three-point spindles supporting a floating abrasive platen. Fig. 2 is an isometric view of three-point fixed-position spindles mounted on a granite base.

Fig. 3 is a cross section view of three-point spindles supporting a floating abrasive platen.

Fig. 4 is a top view of three-point fixed- spindles supporting a floating abrasive platen. Fig. 5 is an isometric view of a workpiece spindle having three-point mounting legs.

Fig. 6 is a top view of a workpiece spindle having multiple circular workpieces.

Fig. 7 is a top view of a workpiece spindle having multiple rectangular workpieces.

Fig. 8 is a top view of workpieces and planetary workholders on an abrasive platen.

Fig. 9 is a cross section view of planetary workholders and a double-sided abrasive platen.

Fig. 10 is a top view of multiple fixed- spindles that support a floating abrasive platen. Fig. 11 is an isometric view of fixed-abrasive coated raised islands on an abrasive disk. Fig. 12 is an isometric view of a fixed-abrasive coated raised island abrasive disk. Fig. 13 is a top view of an automatic robotic workpiece loader for multiple spindles. Fig . 14 is a side view of an automatic robotic workpiece loader for multiple spindles.

Fig . 15 is a top view of an automatic robotic abrasive disk loader for an upper platen.

Fig . 16 is a side view of an automatic robotic abrasive disk loader for an upper platen.

Fig . 17 is a cross section view of adjustable legs on a workpiece spindle.

Fig . 18 is a cross section view of an adjustable spindle leg.

Fig . 19 is a cross section view of a compressed adjustable spindle leg.

Fig . 20 is an isometric view of a compressed adjustable spindle leg.

Fig . 21 is a cross section view of a workpiece spindle with a spindle top debris guard.

Fig . 22 is a cross section view of a workpiece spindle driven by a cooled internal motor.

Fig . 23 is a cross section view of a workpiece spindle driven by an external motor.

Fig . 24 is a cross section view of a recessed workpiece spindle driven by an internal motor.

DETAILED DESCRIPTION OF THE INVENTION

Fig. 1 is an isometric view of an abrading system 45 having three-point fixed- position rotating workpiece spindles supporting a floating rotating abrasive platen.

Three evenly-spaced rotatable spindles 4 (one not shown) having rotating tops 22 that have attached workpieces 6 support a floating abrasive platen 16. The platen 16 has a vacuum, or other, abrasive disk attachment device (not shown) that is used to attach an annular abrasive disk 20 to the precision-flat platen 16 abrasive-disk mounting surface 8. The abrasive disk 20 is in flat abrasive surface contact with all three of the workpieces 6. The rotating floating platen 16 is driven through a spherical-action universal-joint type of device 10 having a platen drive shaft 12 to which is applied an abrasive contact force 14 to control the abrading pressure applied to the workpieces 6. The workpiece rotary spindles 4 are mounted on a granite, or other material, base 24 that has a flat surface 26. The three workpiece spindles 4 have spindle top surfaces that are co-planar. The workpiece spindles 4 can be interchanged or a new workpiece spindle 4 can be changed with an existing spindle 4 where the flat top surfaces of the spindles 4 are co-planar. Here, the equal-thickness workpieces 6 are in the same plane and are abraded uniformly across each individual workpiece 6 surface by the platen 16 precision- flat planar abrasive disk 20 abrading surface. The planar abrading surface 8 of the floating platen 16 is approximately co-planar with the flat surface 26 of the granite base 24.

The spindle 4 rotating surfaces spindle tops 22 can driven by different techniques comprising spindle 4 internal spindle shafts (not shown), external spindle 4 flexible drive belts (not shown) and spindle 4 internal drive motors (not shown). The individual spindle 4 spindle tops 22 can be driven independently in both rotation directions and at a wide range of rotation speeds including very high speeds of 10,000 surface feet per minute (3,048 meters per minute). Typically the spindles 4 are air bearing spindles that are very stiff to maintain high rigidity against abrading forces and they have very low friction and can operate at very high rotational speeds. Suitable roller bearing spindles can also be used in place of air bearing spindles.

Abrasive disks (not shown) can be attached to the spindle 4 spindle tops 22 to abrade the platen 16 annular flat surface 8 by rotating the spindle tops 22 while the platen 16 flat surface 8 is positioned in abrading contact with the spindle abrasive disks that are rotated in selected directions and at selected rotational speeds when the platen 16 is rotated at selected speeds and selected rotation direction when applying a controlled abrading force 14. The top surfaces 2 of the individual three-point spindle 4 rotating spindle tops 22 can be also be abraded by the platen 16 planar abrasive disk 20 by placing the platen 16 and the abrasive disk 20 in flat conformal contact with the top surfaces 2 of the workpiece spindles 4 as both the platen 16 and the spindle tops 22 are rotated in selected directions when an abrading pressure force 14 is applied. The top surfaces 2 of the spindles 4 abraded by the platen 16 results in all of the spindle 4 top surfaces 2 being in a common plane.

The granite base 24 is known to provide a time-stable precision-flat surface 26 to which the precision-flat three-point spindles 4 can be mounted. One unique capability provided by this abrading system 18 is that the primary datum-reference can be the fixed-position granite base 24 flat surface 26. Here, spindles 4 can all have the precisely equal heights where they are mounted on a precision-flat surface 26 of a granite base 24 where the flat surfaces of the spindle tops 2 are co-planar with each other.

When the abrading system is initially assembled it can provide extremely flat abrading workpiece 6 spindle 4 top 22 mounting surfaces and extremely flat platen 16 abrading surfaces 8. The extreme flatness accuracy of the abrading system 18 provides the capability of abrading ultra-thin and large-diameter and high- value workpieces 6, such as semiconductor wafers, at very high abrading speeds with a fully automated workpiece 6 robotic device (not shown).

In addition, the system 18 can provide unprecedented system 18 component flatness and workpiece abrading accuracy by using the system 18 components to "abrasively dress" other of these same-machine system 18 critical components such as the spindle tops 22 and the platen 16 planar-surface 8. These spindle top 22 and the platen 16 annular planar surface 8 component dressing actions can be alternatively repeated on each other to progressively bring the system 18 critical components comprising the spindle tops 22 and the platen 16 planar-surface 8 into a higher state of operational flatness perfection than existed when the system 18 was initially assembled. This system 18 self-dressing process is simple, easy to do and can be done as often as desired to reestablish the precision flatness of the system 18 component or to improve their flatness for specific abrading operations.

This single-sided abrading system 18 self-enhancement surface-flattening process is unique among conventional floating-platen abrasive systems. Other abrading systems use floating platens but these systems are typically double-sided abrading systems.

These other systems comprise slurry lapping and micro-grinding (flat-honing) systems that have rigid bearing- supported rotated lower abrasive coated platens. They also have equal-thickness flat-surfaced workpieces in flat contact with the annular abrasive surfaces of the lower platens. The floating upper platen annular abrasive surface is in abrading contact with these multiple workpieces where these multiple workpieces support the upper floating platen as it is rotated. The result is that the floating platens of these other floating platen systems are supported by a single-item moving-reference device, the rotating lower platen.

Large diameter rotating lower platens that are typically used for double-sided slurry lapping and micro-grinding (flat-honing) often have substantial abrasive-surface out-of-plane variations. These undesired abrading surface variations are due to many causes comprising: relatively compliant (non-stiff) platen support bearings that transmit or magnify bearing dimension variations to the outboard tangential abrading surfaces of the lower platen abrasive surface; radial and tangential out-of-plane variations in the large platen surface; time-dependent platen material creep distortions; abrading machine operating-temperature variations that result in expansion or shrinkage distortion of the lower platen surface; and the constant wear-down of the lower platen abrading surface by abrading contact with the workpieces that are in moving abrading contact with the lower platen abrasive surface. The single-sided abrading system 18 is completely different than the double-sided system (not-shown).

The floating platen 16 system 18 performance is based on supporting a floating abrasive platen 16 on the top surfaces 2 of three-point spaced fixed-position rotary workpiece spindles 4 that are mounted on a stable machine base 24 flat surface 26 where the top surfaces 2 of the spindles 4 are precisely located in a common plane. The top surfaces 2 of the spindles 4 can be approximately or substantially co-planar with the precision-flat surface 26 of a rigid fixed-position granite, or other material, base 24 or the top surfaces 2 of the spindles 4 can be precisely co-planar with the precision-flat surface 26 of a rigid fixed-position granite, or other material, base 24. The three-point support is required to provide a stable support for the floating platen 16 as rigid components, in general, only contact each other at three points. As an option, additional spindles 4 can be added to the system 18 by attaching them to the granite base 24 at locations between the original three spindles 4.

This three-point workpiece spindle abrading system 18 can also be used for abrasive slurry lapping (not shown), for micro-grinding (flat-honing) (not shown) and also for chemical mechanical planarization (CMP) (not shown) abrading to provide ultra-flat abraded workpieces 6.

Fig. 2 is an isometric view of three-point fixed-position spindles mounted on a granite base. A granite base 36 has a precision- flat top surface 28 that supports three attached workpiece spindles 34 that have rotatable driven tops 32 where flat-surfaced workpieces 30 are attached to the flat-surfaced spindle tops 32.

Fig. 3 is a cross section view of three-point fixed-position spindles supporting a rotating floating abrasive platen. A floating circular platen 44 has a spherical-action rotating drive mechanism 50 having a drive shaft 58 where the platen 44 rotates about an axis 54. Three workpiece spindles 62 (one not shown) having rotatable spindle tops 38 that have flat top surfaces 66 are mounted to the top precision-flat surface 56 of a machine base 68 that is constructed from granite, metal or composite or other materials. The flat top surfaces of the spindle tops 38 are all in a common plane 52 where the spindle plane 52 is precisely co-planar with the top flat surface 56 of the machine base 68. Equal-thickness flat-surfaced workpieces 40 are attached to the spindle top 38 flat surfaces 66 by a vacuum, or other, disk attachment device where the top surfaces of the three workpieces 40 are mutually contacted by the abrading surface 64 of an annular abrasive disk 42 that is attached to the platen 44. The platen 44 disk attachment surface 46 is precisely flat and the precision-thickness abrasive disk 42 annular abrasive surface 64 is precisely co-planar with the platen 44 disk attachment surface 46. The annular abrasive surface 64 is precisely co-planar with the flat top surfaces of each of the three independent spindle top 38 flat surfaces 3 and also, co-planar with the spindle plane 52. The floating platen 44 is supported by the three equally- spaced spindles 62 where the flat disk attachment surface 46 of the platen 44 is co-planar with the top surface 56 of the machine base 68. The three equally-spaced spindles 62 of the three-point set of spindles 62 provide stable support to the floating platen 44. The spherical platen 44 drive mechanism 50 restrains the platen 44 in a circular platen 44 radial direction. The spindle tops 38 are driven (not shown) in either clockwise or counterclockwise directions with rotation axes 48 and 60 while the rotating platen 44 is also driven.

Typically, the spindle tops 38 are driven in the same rotation direction as the platen 44. The workpiece spindle 62 tops 38 can be rotationally driven by motors (not shown) that are an integral part of the spindles 62 or the tops 38 can be driven by internal spindle shafts (not shown) that extend through the bottom mounting surface of the spindles 62 and into or through the granite machine base 68 or the spindles 62 can be driven by external drive belts (not shown).

Fig. 4 is a top view of three -point fixed- spindles supporting a floating abrasive platen. Workpieces 69c are attached to three rotatable spindles 69a where the workpieces 69c are in abrading contact with an annular band of abrasive 69b where the workpieces 69c overhang the outer periphery of the abrasive 69b by a distance 69d and overhang the inner periphery of the abrasive 69b by a distance 69f. Each of the three spindles 69a are shown separated by an angle 69e of approximately 120 degrees to provide three-point support of the rotating platen (not shown) having an annular band of abrasive 69b.

Fig. 5 is an isometric view of a workpiece spindle having three-point mounting legs. The workpiece rotary spindle 78 has a rotary spindle top 80 that has a precision- flat surface 82 to which is attached a precision-flat vacuum chuck device 72 that has co- planar opposed flat surfaces. A flat-surfaced workpiece 74 has an exposed flat surface 76 that is abraded by an abrasive coated platen (not shown). The workpiece spindle 78 is three-point supported by spindle legs 70. The workpiece 74 shown here has a diameter of 12 inches and is supported by a spindle 78 having a 12 inch diameter and a rotary spindle top 80 top flat surface 82 that has a diameter of 12 inches. Fig. 6 is a top view of a workpiece spindle having multiple circular workpieces. A workpiece rotary spindle 84 having three-point support legs 88 where the spindle 84 supports small circular flat-surfaced workpieces 86 that are abraded by an abrasive coated platen (not shown). Fig. 7 is a top view of a workpiece spindle having multiple rectangular workpieces. A workpiece rotary spindle 92 has a spindle diameter 96 and three-point support legs 94 where the spindle 92 supports small circular flat-surfaced workpieces 90 that are abraded by an abrasive coated platen (not shown). Fig. 8 is a top view of prior art pin-gear driven planetary workholders and workpieces on an abrasive platen. A rotating annular abrasive coated platen 106 and three planetary workholder disks, 110, 116 and 98 that are driven by a platen 106 outer periphery pin-gear 104 and a platen 106 inner periphery pin-gear 102 are shown.

Typically the outer periphery pin-gear 104 and the inner periphery pin-gear 102 are driven in opposite directions where the three planetary workholder disks 110, 116 and 98 rotate about a workholder rotation axis 108 but maintain a stationary position relative to the platen 106 rotation axis 112 or they slowly rotate about the platen 106 rotation axis 112 as the platen 106 rotates about the platen rotation axis 112. The outer pin-gears 104 and the inner pin- gears 102 rotate independently in either rotation direction and at different rotation speeds to provide different rotation speeds of the workholder disks 110, 116 and 98 about the workholder rotation axes 108 and also to provide different rotation directions and speeds of the workholders disks 110, 116 and 98 about the platen 106 rotation axis 112. A single individual large-diameter flat-surfaced workpiece 100 is positioned inside the rotating workholder 98 and multiple small-diameter flat-surfaced workpieces 114 are positioned inside the rotating workholder 116. The workholder 110 does not contain a workpiece.

Fig. 9 is a cross section view of prior art planetary workholders, workpieces and a double-sided abrasive platen. The abrading surface 120 of a rotating upper floating platen 128 and the abrading surface 142 of a rotating lower rigid platen 134 are in abrading contact with flat-surfaced workpieces 122 and 126. A planetary workholder 118 contains a single large-sized workpiece 122 and the planetary workholder

132contains multiple small-sized workpieces 126. The planetary flat-surfaced workholder disks 118 and 132 rotate about a workholder axis 130 and the workholder disks 118 and 132 are driven by outer periphery pin-gears 146 and inner periphery pin- gears 136. The inner periphery pin-gears 136 are mounted on a rotary drive spindle that has a spindle shaft 138. The rigid-mounted lower platen 134 is supported by platen bearings 140. The floating upper spindle 128 is driven by a spherical rotation device 124 that allows the platen 128 to be conformably supported by the equal-thickness workpieces 122 and 126 that are supported by the lower rigid platen 134.

Fig. 10 is a top view of multiple fixed-spindles that support a floating abrasive platen. A flat-surfaced granite base 152 supports multiple fixed-position air bearing spindles 148 that have rotating flat-surfaced tops 150. The multiple spindles 148 support a floating abrasive platen (not shown) flat abrading surface on the multiple spindle top 150 flat surfaces that are all co-planar. Fig. 11 is an isometric view of fixed-abrasive coated raised islands on an abrasive disk. Abrasive particle 156 coated raised islands 158 are attached to an abrasive disk 154 backing 160. Fig. 12 is an isometric view of a flexible fixed- abrasive coated raised island abrasive disk. Abrasive particle coated raised islands 162 are attached to an abrasive disk 166 backing 164.

Fig. 13 is a top view of an automatic robotic workpiece loader for multiple spindles. An automated robotic device 184 has a rotatable shaft 182 that has an arm 180 to which is connected a pivot arm 178 that, in turn, supports another pivot arm 190. A pivot joint 188 joins pivot arms 190 and 178 and pivot joint 186 joins pivot arms 178 and 180. A workpiece carrier holder 194 attached to the pivot arm 190 holds a workpiece carrier 196 that contains a workpiece 168 where the robotic device 184 positions the workpiece 168 and carrier 196 on and concentric with the workpiece rotary spindle 192. Other workpieces 172 and carriers 170 are shown on a moving workpiece transfer belt 176 where they are picked up by the carrier holder 174. The workpieces 168 and 172 and workpiece carriers 196, 170 can also be temporarily stored in other devices comprising cassette storage devices (not shown). The workpieces 168, 172 and workpiece carriers 196, 170 can also be removed from the spindles 192 after the workpieces 196, 170 are abraded and the workpieces 168, 172 and workpiece carriers 196, 170 can then be placed in or on a moving belt (not shown) or a cassette device (not shown). The workpieces 168, 172 can also optionally be loaded directly on the spindles 192 without the use of the workpiece carriers 196, 170. Access for the robotic device 184 is provided in the open access area between two wide-spaced adjacent spindles 192.

Fig. 14 is a side view of an automatic robotic workpiece loader for multiple spindles. An automated workpiece loader device 206 (partially shown) can be used to load workpieces 204, 212 onto spindles 214 that have spindle tops that have flat surfaces 198 and where the spindle tops rotate about the spindle axis 202. A floating platen 210 that is rotationally driven by a spherical-action device 208 has an annular abrasive surface 200 that contacts the equal-thickness workpieces 204 and 212 where the platen 210 is partially supported by abrading contact with the three independent three -point spindles 214 and the abrading pressure on the workpieces 204 and 212 is controlled by controlled force-loading of the spherical action device 208. The spindles 214 are supported by a granite machine base 216.

Fig. 15 is a top view of an automatic robotic abrasive disk loader for an upper platen. An automated robotic device 232 has a rotatable shaft 230 that has an arm 228 to which is connected a pivot arm 234 that, in turn, supports another pivot arm 236. An abrasive disk carrier holder 238 attached to the pivot arm 236 holds an abrasive disk carrier 220 that contains an abrasive disk 222 where the robotic device 232 positions the abrasive disk 222 and disk carrier 220 on and concentric with the platen 218. Another abrasive disk 224 and abrasive disk carrier plate 226 are shown in a remote location where the abrasive disk 224 can also be temporarily stored in other devices comprising cassette storage devices (not shown). Guide or stop devices (not shown) can be used to aid concentric alignment of the abrasive disk 222 and the platen 218 and the robotic device can position the abrasive disk 222 in flat conformal contact with the flat-surfaced platen 218 after which, vacuum (not shown) is applied to attach the disk 222 to the platen 218 flat abrading surface (not shown). Then the pivot arms 236, 234 and 228 and the carrier holder 238 and the disk carrier 220 are translated back to a location away from the platen 218.

Fig. 16 is a side view of an automatic robotic abrasive disk loader for an upper platen. An automated robotic device 260 (partially shown) has a carrier holder plate 242 that has an attached resilient annular disk support pad 258 that supports an abrasive disk 250 that has an abrasive layer 244. The abrasive disk carrier holder 242 that contains an abrasive disk 250 is moved where the robotic device 260 positions the abrasive disk 250 and disk carrier 242 on to and concentric with the platen 256. The resilient layer pad 258 on the carrier holder 242 allows the back-disk-mounting side of the abrasive disk 250 to be in flat conformal contact with the platen 256 abrading surface 254 before the vacuum 246 is activated. The platen has vacuum 246 that is applied through vacuum port holes 248 to attach the abrasive disk 250 to the abrading surface 254 of the platen 256. The floating platen 256 is driven rotationally by a spherical action device 252 to allow the floating platen 256 abrading surface 254 to be in flat contact with equal- thickness flat-surface workpieces (not shown) that are attached with flat surface contact to the flat top rotating component 240 of three three-point spindles 262 (one not shown) that are mounted on a granite base 264. After the abrasive disk 250 is attached to the platen 256 the robotic device 260 carrier holder 242 is withdraw from the platen 256 area.

Fig. 17 is a cross section view of adjustable legs on a workpiece spindle. A rotary workpiece spindle 270 is attached to a granite base 282 by fasteners 278 that are used to bolt the spindle legs 268 to the granite base 282. The spindle 270 has three equally spaced spindle legs 268 that are attached to the bottom portion of the spindle 270 where there is a space gap 272 between the bottom of the spindle and the flat surface 266 of the granite base 282. The spindle 270 has a rotary spindle top 276 that rotates about a spindle axis 274 and the three spindle legs are height-adjusted to align the spindle axis 274 precisely perpendicular with the top surface 266 of the granite base 282. To adjust the height of the spindle leg 268, transverse bolts 280 are tightened to squeeze-adjust the spindle leg 268 where the spindle leg 268 distorts along the spindle axis 274 thereby raising the portion of the spindle 270 located adjacent to the transverse bolts 280 squeeze-adjusted spindle leg 268. After the three spindle legs 268 are adjusted to provide the desired height of the top flat surface of the spindle top 276 and provide the perpendicular alignment of the spindle axis 274 perpendicular with the top surface 266 of the granite base 282, the spindle hold-down attachment bolts 278 are torque- controlled tightened to attach the spindle 270 to the granite base 282. The hold-down bolts 278 can be loosened and the spindle 270 removed and the spindle 270 then brought back to the same spindle 270 location and position on the granite base 282 for re- mounting on the granite base 282 without affecting the height of the spindle top 276 or perpendicular alignment of the spindle axis 274 because the controlled compressive force applied by the hold-down bolts 278 does not substantially affect the desired size- height distortion of the spindle legs 268 along the spindle rotation axis 274. The height adjustments provided by this adjustable spindle leg 268 can be extremely small, as little as 1 or 2 micrometers, which is adequate for precision alignment adjustments required for air bearing spindles 270 that are typically used for the fixed-spindle floating-platen abrasive system (not shown). Also, these spindle leg 268 height adjustments are dimensionally stable over long periods of time because the squeeze forces produced by the transverse bolts 280 do not stress the spindle leg 268 material past its elastic limit. Here, the spindle leg 268 acts as a compression- spring where the spindle leg 268 height can be reversibly changed by changing the force applied by the transverse bolts 280 which is changed by changing the tightening-torque that is applied to these threaded transverse bolts 280.

Fig. 18 is a cross section view of an adjustable spindle leg. A spindle leg 286 has transverse tightening bolts 290 that compress the spindle leg 286 along the axis of the transverse bolts 290. Spindle (not shown) hold-down bolts 288 are threaded to engage threads (not shown) in the granite base 284 but the compressive action applied on the spindle leg 286 by the hold-down bolts 288 along the axis of the hold-down bolt 288 is carefully controlled in concert with the compressive action of the transverse bolts 290 to provide the desired distortion of the spindle leg 286 along the axis of the hold-down bolts 288.

Fig. 19 is a cross section view of a compressed adjustable spindle leg. A spindle leg 296 has transverse tightening bolts 302 that compress the spindle leg 296 along the axis of the transverse bolts 302 by a distortion amount 298. Spindle (not shown) hold- down bolts 300 are threaded to engage threads (not shown) in the granite base 292 but the compressive action applied on the spindle leg 296 by the hold-down bolts 300 along the axis of the hold-down bolt 300 is carefully controlled in relationship with the compressive action of the transverse bolts 302 on the spindle leg 296 to provide the desired distortion 304 of the spindle leg 296 along the axis of the hold-down bolts 300. The transverse bolts 302 create a transverse squeezing distortion 298 that is present on the spindle leg 296 and this transverse distortion 298 produces the desired height distortion 304 of the spindle leg 296. When the spindle leg 296 is distorted by the amount 304, the spindle is raised away from the surface 294 of the granite base 292 by this distance amount 304.

Fig. 20 is an isometric view of a compressed adjustable spindle leg. A spindle leg 316 has transverse tightening bolts 310 that compress the spindle leg 308 along the axis of the transverse bolts 310. The spindle 314 has attached spindle legs 316 that have spindle hold-down bolts 318 that are threaded to engage threads (not shown) in the granite base 322. The compressive action applied on the spindle leg 316 by the hold- down bolts 318 along the axis of the hold-down bolt 318 is carefully controlled in concert with the compressive action of the transverse bolts 310 to provide the desired distortion 324 of the spindle leg 316 along the axis of the hold-down bolts 318. The transverse bolts 310 create a transverse squeezing distortion that is present on the spindle leg 316 and this transverse distortion produces the desired height distortion 324 of the spindle leg 316. When the spindle leg 316 is distorted by the amount 324, the spindle 314 is raised away from the surface 320 of the granite base 322 by this distance amount 324. A spindle leg 316 integral flat-base 326 having a distortion-isolation wall 306 provides flat-contact of the spindle leg 316 with the flat surface 320of the granite base 322. The distortion-curvature 308 of the spindle leg 316 is shown where the spindle leg 316 leg-base 326 remains flat where it contacts the granite base 322 flat surface 320. A narrow but stiff bridge section 312 that is an integral portion of the spindle leg 316 isolates the spindle leg 316 distortion 324 from the body of the spindle 314. Fig. 21 is a cross section view of a workpiece spindle with a spindle top debris guard. A cylindrical workpiece spindle 1148 has a rotary top 1156 that rotates about a spindle axis 1154 where the spindle top 1156 has a circumferential separation line 1152 that separates the spindle top 1156 from the spindle 1148 base 1153. Where these spindles 1148 are used in abrading atmospheres, water mist, abrading debris and very small sized abrasive particles are present in the atmosphere surrounding the spindle 1148. To prevent entry of this debris, water moisture and abrasive particles in the spindle 1148 separation line 1152 area, a circumferential drip-shield 1150 is provided where the drip shield 1150 has a drip lip 1151that extends below the separation line 1152. Unwanted debris material and water simply drips off the surface of the drip shield 1150. Build-up of debris matter on the drip shield 1150 is typically avoided because of the continued presence of abrasive coolant water that continually washes the surface of the drip shield 1150. When the workpiece spindles 1148 are used in abrading processes, often special chemical additives are added to the coolant water to enhance the abrading action on workpieces (not shown) in abrading procedures such as chemical mechanical planarization. Both the cylindrical spindle 1148 cylindrical drip shields 1150 and the spindles 1148 are constructed from materials that are resistant to materials comprising water coolants, chemical additives, abrading debris and abrasive particles.

Fig. 22 is a cross section view of a workpiece spindle driven by a cooled internal motor. A spindle 346 has a flat-surfaced rotary spindle-top 354 where the spindle-top 354 is rotated about a spindle axis 352. The spindle 346 is mounted on a machine base 342 by fasteners that attach spindle support legs 344 that are attached to the spindle 346 body to the machine base 342. The spindle-top 354 is driven by a hollow shaft 362 that is driven by a motor armature 350 that is driven by an internal motor winding 348. The spindle-top 354 hollow drive shaft 362 has an attached hollow shaft 368 that has an attached to a stationary rotary union 366 that is coupled to a vacuum source 364 that supplies vacuum to the spindle-top 354. A water jacket 356 is shown wrapped around the spindle 346 body where the water jacket 356 has temperature-controlled coolant water 358 that enters the water jacket 356 and exits the water jacket as exit water 360 where the water 358 cools the spindle 346 to remove the heat generated by the motor windings 348 to prevent thermal distortion of the spindle 346 and thermal displacement of the spindle-top 354.

Fig. 23 is a cross section view of a workpiece spindle driven by an external motor. A spindle 376 having a flat-surfaced spindle-top 374 that rotates about a spindle axis 372 is mounted to a machine base 370. An external motor 386 drives the spindle-top 374 with a bellows-type drive coupler 378 that allows slight misalignments between the motor 386 rotation axis and the spindle-top 374 axis of rotation 372. The bellows-type coupler 378 provides stiff torsional load capabilities for accelerating or decelerating the spindle-top 374. A rotary union device 384 supplies vacuum 382 to the spindle-top 374 through a flexible tube 380. The motor 386 is attached to the machine base 370 with motor brackets 388.

Fig. 24 is a cross section view of a recessed workpiece spindle driven by an internal motor. A rotary workpiece air bearing spindle 406 is mounted on a machine base 416 with spindle legs 408 that are attached to the spindle 406 body. The spindle 406 has a flat-surfaced spindle-top 396 that rotates about a spindle axis 402 where the spindle-top 396 has a flat top surface 404. The spindle-top 396 has a hollow spindle shaft 412 that is driven by an internal motor armature 400 that is driven by an electrical motor winding 398. The spindle 406 is recessed into the machine base 416 because the spindle 406 support legs 408 are attached to the spindle 406 body near the top of the spindle 406. The spindle 406 is attached to a spherical rotor 392 with fasteners 394 where the rotor 392 is mounted in a spherical base 390 that is attached to the machine base 416. After co-planar alignment of spindle-tops 396 with other spindle-tops 396 (not shown), the spherical rotor 392 is locked to the spherical base 390 with fasteners 410. This spindle 406 spherical mount system comprising the rotor 392 and base 390, allows inexpensive, but dimensionally stable, machine bases having non-precision flat top surfaces to be used to mount the spindles 406 where the spindle-tops 396 can be precisely aligned to be co- planar with each other.

Here, the separation-line 414 between the spindle-top 396 and the spindle 406 body is a close distance from the spindle 406 mounting surface of the machine base 416. Because the separation distance is short, heat from the motor electrical winding 398 that tends to thermally expand the length of the spindle 406 is minimized and the there is little thermally-induced vertical movement of the spindle-top 396 due to the motor heat. Also, the pressurized air that is supplied to the air bearing spindle 406 expands as it travels through the spindle 406 which lowers the temperature of the spindle air. This cool spindle air exits the spindle body at the separation line 414 where it cools the spindle 406 internally and at the interface between the spindle-top 396 and the spindle 406 which reduces the thermal-expansion effects from the heat generated by the electrical internal motor windings 398. Thermal growth in the length of the spindles 406 tends to be equal for all three spindles 406 used in the fixed-spindle floating platen abrading systems (not shown). Any spindle 406 thermal distortion effects are uniform across all of the system spindles 406 and there is little affect on the abrading process because the floating abrasive platen simply contacts all of these same-expanded spindles 406 in a three-point contact stance. When the spindles 406 are mounted where the bottom of the spindle 406 extends below the surface of the machine base 416 the effect of the thermal growth of the spindles 406 along the spindle length is diminished.

The spindles 406 are attached to spherical rotors 392 that are mounted in a spherical base 390 where pressurized air or a liquid 420 can be applied through a fluid passageways 418 to allow the spherical rotor 392 to float without friction in the spherical base 390 when the spindle-tops 396 (others not shown) are aligned to be co-planar in a common plane after which vacuum 422 can be applied through fluid passageways 418 to lock the spherical rotor 392 to the spherical base 390 and fasteners 410 can be used to attach the spherical rotor 392 to the spherical base 390. The spherical rotor 392 and the spherical base 390 have a mutually common spherical diameter. Another technique of locking the spherical rotor 392 to the spherical base 390 after the spindle-tops 396 are aligned to be co-planar is to apply a liquid adhesive 426 in the gap between a removable bracket 428 that is attached to the spherical rotor 392 and a removable bracket 424 that is attached to the spherical base 390 where the liquid adhesive 426 becomes solidified and provides structural locking attachment of the spherical rotor 392 to the spherical base 390. For future co-planar realignment of the spindle-tops 396 to be co-planar, the brackets 428 and 424 that are adhesively bonded together can be removed by detaching them from the rotor 392 and the housing base 390 and other individual replacement brackets 428 and 424 can be attached to the rotor 392 and the housing base 390. Then, when the spindle-tops 396 are aligned to be co-planar an adhesive 426 is applied in the gap between a removable bracket 428 that is attached to the spherical rotor 392 and a removable bracket 424 that is attached to the spherical base 390 to bond the spherical rotor 392 to the spherical base 390.

The spindle-tops 396 can be aligned to be co-planar with the use of measurement instruments (not shown) or with the use of laser alignment devices (not shown). Also, a very simple technique that can be used for co-planar alignment of the spindle-tops 396 is to bring a precision-flat surface of a floating platen (not shown) annular abrading surface into flat surfaced contact with the spindle-tops 396 where pressurized air or a liquid 420 can be applied through a fluid passageways 418 to form a spherical-action fluid bearing that allows the spherical rotor 392 to float without friction in the spherical base 390. Here, the spindle-tops 396 are aligned to be co-planar in a common plane after which vacuum 422 can be applied through fluid passageways 418 to lock the spherical rotor 392 to the spherical base 390. If desired, pressurized air can be applied to the internal passageways (not shown) connected to the spindle-tops 396 flat surfaces during the procedure of co- planar alignment of the spindle-tops 396. This is done to reduce the friction between the spindle-tops 396 and the platen abrading surface which provides assurance that the spindle-tops 396 and the platen abrading surface are mutually in flat contact with each other. After co-planar alignment of the spindle-tops 396, vacuum can be applied to these spindle-tops 396 flat surfaces to temporarily bond the spindle-tops 396 to the platen before or while vacuum 422 is applied through fluid passageways 418 to lock the spherical rotor 392 to the spherical base 390. Then, when the spindle-tops 396 are aligned to be co- planar, an adhesive 426 is applied in the gap between a removable bracket 428 that is attached to the spherical rotor 392 and a removable bracket 424 that is attached to the spherical base 390 to rigidly bond the spherical rotor 392 to the spherical base 390.

This same technique of applying fluid pressure and vacuum to the fluid passageways 418 to form a spherical-action fluid bearing that allows the spherical rotor 392 to float without friction in the spherical base 390 can be used with the fasteners 410 to attach the spherical rotor 392 to the spherical base 390. Another alternative, but closely related, spindle-tops 396 co-planar alignment technique is to apply pressurized fluid and then vacuum to vacuum abrasive mounting holes in the platen abrading surface to perform the procedure of co-planar alignment of the spindle-tops. Those abrasive disk vacuum holes in the platen that are not in contact with the spindle-tops 396 are temporarily plugged using adhesive tape or by other means during the spindle-tops 396 co-planar alignment procedure.

The fixed-spindle floating platen machine has a number of different characteristics that allow it to be configured in different ways and perform different tasks. These system characteristics and capabilities are described here.

An at least three -point, fixed-spindle floating-platen abrading machine comprising:

a) three rotary spindles having spindle bodies and having rotatable flat-surfaced spindle-tops that each have a spindle-top axis of rotation at a center of the rotatable flat- surfaced spindle top;

b) an abrading machine base having a horizontal, flat top surface and a spindle-circle where the spindle-circle is located approximately at the center of a top surface of the machine base and the spindle-circle is coincident with the machine base top surface;

c) wherein at least three rotary spindles are located with approximately equal spaces between each of them and the spindle-tops' axes of rotation intersect the machine base spindle-circle and the spindles are attached to the machine base top surface at those spindle-circle locations;

d) wherein the three spindle-top flat surfaces are co-planar with each other;

e) a floating, rotatable abrading platen having a flat annular abrading surface where the platen is supported by and rotationally driven about a platen rotation axis located at a rotational center of the platen by a spherical-action rotation device located at the rotational center of the platen and the spherical-action rotation device restrains the platen in a radial direction relative to the platen axis of rotation and the platen axis of rotation is concentric with the machine base spindle-circle;

f) wherein the spherical-action rotation device allows spherical motion of the floating platen about the rotational center of the platen where the platen abrading surface is nominally horizontal;

g) flexible abrasive disk components having annular bands of abrasive coated flat surfaces where a selected flexible abrasive disk is attached in flat conformal contact with the platen abrading surface by disk attachment techniques where the attached abrasive disk is concentric with the platen abrading surface;

h) wherein equal-thickness workpieces having parallel or approximately parallel opposed flat surfaces are attached in flat-surfaced contact with the flat surfaces of the spindle-tops and the platen is vertically moveable to allow the abrasive surface of the abrasive disk that is attached to the platen abrading surface to contact the top surfaces of the workpieces;

i) wherein the at least three spindle-tops having the attached workpieces can be rotated about the respective spindles' axes and the platen can be rotated about the platen rotation axis where the flat abrasive surface of the abrasive disk attached to the platen is in force-controlled abrading pressure with the workpieces to single-side abrade the workpieces.

The same flat lapping machine wherein flat-surfaced disk-type devices comprising workpieces, workpiece carriers, abrasive conditioning rings and abrasive disks where selected flat-surfaced disk-type devices are attached to the at least three spindles' spindle-tops and where the machine base is granite. Also, where the machine at least three spindles are air bearing spindles where the rotary spindle-tops are rotated by external motors that are attached to the spindle-tops or the rotary spindle-tops are rotated by internal motors that are integral to the spindles. In addition, the machine's individual workpiece spindles have adjustable-height at least three-point support legs where the at least three support legs are attached to a supporting surface of each respective spindle and the spindle support legs are positioned around the periphery of the respective spindle bodies with approximately equal space distances between the at least three support legs to form an at least three-point support of the individual workpiece spindles and where the flat surfaces of the spindle-tops of the at least three spindles can be aligned to be co- planar by adjusting the heights of the individual spindle support legs that support the individual at least three spindles.

The same flat lapping machine wherein the platen flexible abrasive disk articles are selected from the group consisting of: flexible abrasive disks, flexible raised-island abrasive disks, flexible abrasive disks with resilient backing layers, flexible abrasive disks with resilient backing layers having a vacuum-seal polymer backing layer, flexible abrasive disks having attached solid abrasive pellets, chemical-mechanical planarization resilient disk pads that are suitable for use with liquid abrasive slurries, chemical- mechanical planarization resilient disk pads having nap covers, shallow-island chemical- mechanical planarization abrasive disks, shallow-island abrasive disks with resilient backing layers having a vacuum-seal polymer backing layer, and flat-surfaced slurry abrasive plate disks. Also, the same machine where auxiliary workpiece spindles in excess of the at least three workpiece spindles which are primary workpiece spindles are attached to the machine base precision-flat surface and where the more than three auxiliary workpiece spindles are each positioned between sets of two adjacent primary three-point equally spaced workpiece spindles, the auxiliary spindle-tops having centers of rotation that are positioned on the machine base spindle-circle, and the top surfaces of the spindle-tops of the auxiliary spindles are co-planar with the top surfaces of the spindle-tops of the primary spindles.

The same flat lapping machine where the three-point fixed-spindle floating-platen is configured to abrade the flat-surfaced spindle-tops with a structure comprising:

a) the at least three spindle-top flat surfaces are co-planar with each other;

b) flexible abrasive disk articles having annular bands of abrasive coated surfaces where a selected flexible abrasive disk is attached in flat conformal contact with the platen abrading surface; c) and wherein the platen can be moved vertically along the platen rotation axis by the spherical-action platen rotation device to allow the abrasive surface of the abrasive disk that is attached to the platen abrading surface to contact the top surfaces of the spindle-tops;

d) providing that the at least three spindle-tops are rotated about their respective spindle axes and the platen is rotated about the platen rotation axis to abrade the spindle-tops while the moving platen abrading surface is in force-controlled abrading pressure with the spindle-tops. Furthermore, a process is described where the lapper machine can be used for abrading flat-surfaced workpieces using a three-point fixed-spindle floating- platen abrading machine comprising:

a) providing at least three primary rotary spindles having rotatable flat-surfaced spindle-tops that each have a spindle-top axis of rotation at the center of the rotatable flat-surfaced spindle top;

b) providing an abrading machine base having a horizontal, flat top surface and a spindle-circle where the spindle-circle is located at the approximate center of the machine base top surface and the spindle-circle is coincident with the machine base top surface;

c) providing that at least three rotary spindles are located with approximately equal spaces between each of them and the spindle-tops' axes of rotation intersect the machine base spindle-circle and the spindles are attached to the machine base top surface at those spindle-circle locations;

d) providing that the three spindle-top flat surfaces are precisely co-planar with each other;

e) providing a floating rotatable abrading platen having a flat annular abrading surface where the platen is supported by and rotationally driven about a platen rotation axis located at the rotational center of the platen by a spherical-action rotation device located at the rotational center of the platen and the spherical-action rotation device restrains the platen in a radial direction relative to the platen axis of rotation and the platen axis of rotation is concentric with the machine base spindle-circle;

g) providing that the spherical-action rotation device allows spherical motion of the floating platen about the rotational center of the platen where the platen abrading surface is nominally horizontal;

h) providing flexible abrasive disk articles having annular bands of abrasive coated flat surfaces where a selected flexible abrasive disk is attached in flat conformal contact with the platen abrading surface by disk attachment techniques where the attached abrasive disk is concentric with the platen abrading surface;

j) providing that equal-thickness workpieces having parallel or approximately parallel opposed flat surfaces are attached in flat-surfaced contact with the flat surfaces of the at least three spindle-tops and the platen is moved vertically to allow the abrasive surface of the abrasive disk that is attached to the platen abrading surface to contact the top surfaces of the workpieces;

k) wherein the at least three spindle-tops having the attached workpieces are rotated about the respective spindles' axes and the platen is rotated about the platen rotation axis to single-side abrade the workpieces while the moving platen abrading surface is in force-controlled abrading pressure with the workpieces. Additionally, a process is described of abrading an abrading surface of a floating platen that is a component of a three-point fixed-spindle floating-platen abrading machine to recondition or reestablish the planar flatness of the platen abrading surface comprising: a) providing at least three primary rotary spindles having rotatable flat- surfaced spindle-tops that have a spindle-top axis of rotation at the center of the rotatable flat- surfaced spindle top;

e) providing a floating rotatable abrading platen having a flat annular abrading surface where the platen is supported by and rotationally driven about a platen rotation axis located at the rotational center of the platen by a spherical-action rotation device located at the rotational center of the platen and the spherical-action rotation device restrains the platen in a radial direction relative to the platen axis of rotation and the platen axis of rotation is concentric with the machine base spindle-circle; f) providing that the spherical-action rotation device allows spherical motion of the floating platen about the rotational center of the platen where the platen abrading surface is nominally horizontal;

g) attaching selected flexible abrasive disks or abrasive conditioning rings having flat- surfaced abrasive coating surfaces to the flat surfaces of the at least three spindles' spindle-tops;

h) moving the platen vertically along the platen rotation axis by the spherical-action platen rotation device to allow the platen abrading surface to contact the abrasive surfaces of the selected flexible abrasive disks or the selected abrasive conditioning rings that are attached to the spindle-top flat surfaces of the at least three spindles; i) rotating the at least three spindle-tops having the attached selected abrasive disks or abrasive conditioning rings about the respective spindles' axes and rotating the platen about the platen rotation axis to abrade the abrading-surface of the platen with the selected abrasive disks or abrasive conditioning rings while the moving platen abrading surface is in force-controlled abrading pressure with the selected abrasive disks or abrasive conditioning rings.

Also, the process of abrading an abrading surface of a floating platen is described where the abrading surface of the floating platen is abraded to recondition or reestablish planar flatness of the platen abrading surface using conditioning rings where circular- shaped conditioning rings having a flat-surfaced abrasive coated annular band are attached to the at least three spindle-tops where the conditioning rings annular abrasive surfaces have equal heights above each spindle-top wherein the at least three spindle- tops having the attached conditioning rings are rotated about the respective spindles' axes while the moving platen abrading surface is in force-controlled abrading pressure with the spindle-top conditioning rings.

A process is described of abrading an abrading surface of an abrasive disk that is attached to the abrading surface of the floating platen that is a component of a fixed- spindle floating platen abrading machine is abraded to recondition or reestablish the planar flatness of the abrading surface of the abrasive disk comprising:

a) providing at least three primary rotary spindles having rotatable flat-surfaced spindle-tops that have a spindle-top axis of rotation at the center of the rotatable flat- surfaced spindle top;

f) providing that the spherical-action rotation device allows spherical motion of the floating platen about the rotational center of the platen where the platen abrading surface is nominally horizontal;

i) moving the platen vertically along the platen rotation axis by the spherical-action platen rotation device to allow the abrading surface of the abrasive disk that is attached to the abrading surface of the platen to contact the abrasive surfaces of the selected flexible abrasive disks or the selected abrasive conditioning rings that are attached to the spindle-top flat surfaces of the at least three spindles;

j) rotating the at least three spindle-tops having the attached selected abrasive disks or abrasive conditioning rings about the respective spindles' axes and rotating the platen about the platen rotation axis to abrade the abrasive surface of the abrasive disk that is attached to the abrading-surface of the platen while the moving abrasive surface of the abrasive disk that is attached to the abrading surface of the platen is in force-controlled abrading pressure with the selected abrasive disks or abrasive conditioning rings.

The process of abrading an abrading surface of an abrasive disk is also described where the abrading surface of an abrasive disk that is attached to the abrading surface of the floating platen is abraded to recondition or reestablish the planar flatness of the abrading surface of the abrasive disk using conditioning rings where circular-shaped conditioning rings having a flat-surfaced abrasive coated annular band are attached to the at least three spindle-tops where the conditioning ring annular abrasive surfaces have equal heights above each spindle-top wherein the at least three spindle-tops having the attached conditioning rings are rotated about their respective spindles' axes while the moving abrasive surface of the abrasive disk that is attached to the abrading surface of the platen is in force-controlled abrading pressure with the spindle-top abrasive conditioning rings.

The fixed-spindle floating platen lapping machine is also described where the three -point fixed-spindle floating-platen machine has an automated robotic workpiece loading apparatus that can selectively install and remove workpieces for a three -point fixed-spindle floating-platen abrading machine apparatus comprising: an automated robotic device that can sequentially transport and install selected flat workpieces or flat workpiece carrier devices on the top flat surface on all at least three spindle-top flat surfaces by picking selected individual workpieces or workpiece carrier devices from a corresponding workpiece or workpiece carrier storage device and can transport it to a select spindle spindle-top where it is positioned concentrically with the rotational center of the rotatable spindle-top wherein the workpiece or workpiece carrier is attached to the spindle-top with vacuum for abrading action on the workpieces by the abrading machine apparatus; and the same automated robotic device sequentially can remove selected flat workpieces or flat workpiece carrier devices from the top flat surface on all three spindle- top flat surfaces by picking the individual workpieces or workpiece carriers from a selected spindle-top and transporting them to a corresponding workpiece or workpiece carrier storage device for storage.

A process is described of loading workpieces using the automated robotic workpiece loading apparatus where workpieces are selectively installed and removed from a three-point fixed- spindle floating-platen abrading machine having: an automated robotic device that sequentially transports and installs selected flat workpieces or flat workpiece carrier devices on the top flat surface on all three spindle-top flat surfaces by picking selected individual workpieces or workpiece carrier devices from a corresponding workpiece or workpiece carrier storage device and transporting it to a select spindle spindle-top where it is positioned concentrically with the rotational center of the rotatable spindle-top wherein the workpiece or workpiece carrier is attached to the spindle-top with vacuum for abrading action on the workpieces by the abrading machine; and the same automated robotic device sequentially can remove selected flat workpieces or flat workpiece carrier devices from the top flat surface on all three spindle-top flat surfaces by picking the individual workpieces or workpiece carriers from a selected spindle-top and transporting them to a corresponding workpiece or workpiece carrier storage device for storage.

The fixed-spindle floating platen lapping machine is also described where the three -point fixed-spindle floating-platen machine has an automated robotic abrasive disk loading apparatus that can selectively install and remove abrasive disks to and from a platen of a three-point fixed-spindle floating-platen abrading machine wherein the automated robotic device sequentially can install selected abrasive disks comprising flexible abrasive disks, flexible raised-island abrasive disks, flexible abrasive disks having attached solid abrasive pellets, chemical mechanical planarization resilient disk pads, shallow-island abrasive disks, flat-surfaced slurry abrasive plate disks and non-abrasive cloth or other material pads are selectively attached to the platen flat-surfaced abrading by picking selected individual abrasive disks from a corresponding abrasive disk storage device and transporting it to the platen abrading surface where it is positioned concentrically with the rotational center of the platen and the flexible abrasive disk is pressed conformably against the abrading surface of the platen wherein the abrasive disk is attached to the platen abrading surface with vacuum for abrading action on the workpieces by the abrading machine; and the same automated robotic device sequentially removes the selected abrasive disk from the flat abrading surface of the platen by picking the abrasive disk from the platen after the abrasive disk attachment vacuum is released and transporting the abrasive disk to an abrasive disk device for storage.

A process is described of loading abrasive disks using the automated robotic abrasive disk where the automated robotic device selectively installs and removes abrasive disks to and from a platen of a three-point fixed-spindle floating-platen abrading machine comprising: an

automated robotic device sequentially installing selected abrasive disks to the platen flat- surfaced abrading by picking selected individual abrasive disks from a corresponding abrasive disk storage device and transporting it to the platen abrading surface; positioning the selected individual adhesive disk concentrically with the rotational center of the platen; attaching the adhesive disk to the platen abrading surface with vacuum for abrading action on the workpieces by the abrading machine and the same automated robotic device can remove selected abrasive disk from the flat abrading surface of the platen by picking the abrasive disk from the platen after the abrasive disk attachment vacuum is released and transporting the abrasive disk.

The fixed-spindle floating platen lapping machine is also described where the spindle-top flat surfaces of the at least three rotary spindles that are mechanically attached to respective at least three rotary spindle two-piece spindle-mount devices' rotatable spindle-mount spherical-action rotors can be aligned to be precisely co-planar with the other spindle-tops' flat surfaces by adjusting the spherical angle of the rotatable spindle- mount spherical-action rotors relative to the respective stationary spindle-mount spherical- bases while the rotatable spindle-mount spherical-action rotor is supported by respective stationary spindle-mount spherical-bases after which the rotary spindle two-piece spindle- mount device' locking devices are engaged to lock the respective rotatable spindle-mount spherical-action rotors to the respective stationary spindle-mount spherical-bases to structurally maintain the co-planar alignment of the at least three spindle-tops' flat surfaces.

A process is described where the fixed-spindle floating platen lapping machine is configured and aligned where the spindle-top flat surfaces of the at least three rotary spindles that are mechanically attached to respective at least three rotary spindle two-piece spindle-mount devices' rotatable spindle-mount spherical-action rotors are aligned to be precisely co-planar with the other spindle-tops' flat surfaces by adjusting the spherical angle of the rotatable spindle-mount spherical-action rotors relative to the respective stationary spindle-mount spherical-bases while the rotatable spindle-mount spherical- action rotor is supported by respective stationary spindle-mount spherical-bases after which the rotary spindle two-piece spindle-mount device' locking devices are engaged to lock the respective rotatable spindle-mount spherical-action rotors to the respective stationary spindle-mount spherical-bases to maintain the co-planar alignment of the at least three spindle-tops' flat surfaces.

Also, a fixed-spindle floating platen lapping machine is also described where the at least three rotary spindles are mechanically attached to respective at least three rotary spindle two-piece spindle-mount devices having rotary spindle two-piece spindle-mount device locking devices where rotatable spindle-mount spherical-action rotors are supported by respective stationary spindle-mount spherical-bases that are attached to a machine base wherein the spindle-top flat surfaces of the individual at least three rotary spindles can be mutually aligned to be co-planar with the other spindle-tops' flat surfaces by adjusting the spherical angle of the respective rotatable spindle-mount spherical-action rotors relative to the respective stationary spindle-mount spherical-bases while the rotatable spindle-mount spherical-action rotors are in intimate flat-surfaced contact with the flat annular abrading surface of the platen after which rotary spindle two-piece spindle- mount device' locking devices are engaged to lock the respective rotatable spindle-mount spherical-action rotors to the respective stationary spindle-mount spherical -bases to structurally maintain the co-planar alignment of the at least three spindle-tops' flat surfaces after the platen abrading surface is separated from contact with the least three rotary spindle tops.

Further a process is described where the fixed-spindle floating platen lapping machine is configured and aligned where the spindle-top flat surfaces of the at least three rotary spindles are mutually aligned to be co-planar with the other spindle-tops' flat surfaces by adjusting the spherical angle of the respective rotatable spindle-mount spherical-action rotors relative to the respective stationary spindle-mount spherical-bases while the rotatable spindle-mount spherical-action rotors are positioned in intimate flat- surfaced contact with the flat annular abrading surface of the platen after which the rotary spindle two-piece spindle-mount device' locking devices are engaged to lock the respective rotatable spindle-mount spherical-action rotors to the respective stationary spindle-mount spherical-bases to structurally maintain the co-planar alignment of the at least three spindle-tops' flat surfaces after the platen abrading surface is separated from contact with the least three rotary spindle tops.

In addition, a fixed-spindle floating platen lapping machine is described where each of the at least three rotary spindles has multiple paired sets of removable rotor mount tabs that are attached to the respective spindle-mount spherical-action rotors and adjacent multiple removable spherical-base tabs that are attached to the respective spindle-mount spherical-action spherical-bases where small gaps exist between the pairs of adjacent respective removable rotor mount tabs and the removable spherical-base tabs wherein a liquid adhesive can be applied in the small gap areas that exist between the pairs of adjacent respective removable rotor mount tabs and the removable spherical-base tabs after the at least three rotary spindles' spindle-tops are aligned to be co-planar with each other wherein the adhesive is solidified and structurally bonds the respective pairs of removable rotor mount tabs and the respective adjacent removable spherical-base tabs together wherein the respective spindle-mount spherical-action rotors are structurally fixtured to the respective spindle-mount spherical-action spherical-bases where the respective spindle-mount spherical-action rotors are prevented from moving relative to the respective spindle-mount spherical-action spherical-bases.

Further, a process is described where the fixed-spindle floating platen lapping machine where each of the at least three rotary spindles has multiple paired sets of removable rotor mount tabs that are attached to the respective spindle-mount spherical- action rotors and adjacent multiple removable spherical -base tabs that are attached to the respective spindle-mount spherical-action spherical-bases where small gaps exist between the pairs of adjacent respective removable rotor mount tabs and the removable spherical- base tabs wherein a liquid adhesive can be applied in the small gap areas that exist between the pairs of adjacent respective removable rotor mount tabs and the removable spherical-base tabs after the at least three rotary spindles' spindle-tops are aligned to be co-planar with each other wherein the adhesive is solidified and structurally bonds the respective pairs of removable rotor mount tabs and the respective adjacent removable spherical-base tabs together wherein the respective spindle-mount spherical-action rotors are structurally fixtured to the respective spindle-mount spherical-action spherical-bases where the respective spindle-mount spherical-action rotors are prevented from moving relative to the respective spindle-mount spherical-action spherical-bases.

Claims

WHAT IS CLAIMED:

1. An at least three-point, fixed-spindle floating platen abrading machine comprising: a) at least three rotary spindles having spindle bodies and having rotatable flat- surfaced spindle-tops that each have a spindle-top axis of rotation at a center of the rotatable flat-surfaced spindle top;

b) the floating platen abrading machine base having a horizontal, flat top surface and a spindle-circle where the spindle-circle is located approximately at the center of a top surface of the machine base and the spindle-circle is coincident with the machine base top surface;

c) wherein the at least three rotary spindles are located with approximately equal spaces between each of the at least three rotary spindles and the spindle tops' axes of rotation intersect the machine base spindle-circle and the at least three rotary spindles are attached to the machine base top surface at those spindle-circle locations;

d) wherein the flat surfaces of the at least three spindle-top are co-planar with each other;

e) a floating rotatable abrading platen having a flat annular abrading surface where the platen is supported by and rotationally driven about a platen rotation axis located at a rotational center of the floating rotatable abrading platen by a spherical-action rotation device located at a rotational center of the floating rotatable abrading platen and the spherical- action rotation device restrains the floating rotatable abrading platen in a radial direction relative to the floating rotatable abrading platen axis of rotation and the floating, rotatable abrading platen axis of rotation is concentric with the machine base spindle-circle;

f) wherein the spherical-action rotation device causes spherical motion of the floating rotatable abrading platen about the rotational center of the platen where the floating rotatable abrading platen abrading surface is nominally horizontal;

g) flexible abrasive disk components having annular bands of abrasive coated flat surfaces and wherein a flexible abrasive disk is attached in flat conformal contact with the floating rotatable abrading platen abrading surface wherein the attached abrasive disk is concentric with the floating rotatable abrading platen abrading surface; h) wherein equal-thickness workpieces having approximately parallel opposed flat surfaces are attached in flat-surfaced contact with the flat surfaces of the spindle- tops and the floating rotatable abrading platen is vertically moveable to allow the abrasive surface of the abrasive disk that is attached to the floating rotatable abrading platen abrading surface to contact the top surfaces of the workpieces; i) wherein the at least three spindle-tops having the attached workpieces can be rotated about respective spindles' axes and the floating rotatable abrading platen can be rotated about the floating rotatable abrading platen rotation axis where the flat abrasive surface of the abrasive disk attached to the platen is in force-controlled abrading pressure with the workpieces to single-side abrade the workpieces.

The machine of claim 1 wherein flat-surfaced disk-type devices comprising workpieces, workpiece carriers, abrasive conditioning rings and abrasive disks where selected flat-surfaced disk- type devices are attached to the at least three spindles' spindle-tops.

3. The machine of claim 1 wherein the machine base is granite.

The machine of claim 1 wherein the at least three spindles are air bearing spindles where the rotary spindle-tops are rotated by external motors that are attached to the spindle-tops or the rotary spindle-tops are rotated by internal motors that are integral to the spindles.

5. The machine of claim 1 where the individual workpiece spindles have adjustable- height at least three-point support legs where the at least three-point support legs are attached to a supporting surface of each respective spindle and the spindle three- point support legs are positioned around the periphery of the respective spindle bodies with approximately equal space distances between the at least three -point support legs to form an at least three-point support of the individual workpiece spindles and where flat surfaces of the spindle-tops of the at least three spindles are adapted to be aligned to be co-planar by adjustable heights of the individual three- point spindle support legs that support the individual at least three spindles.

6. The machine of claim 1 wherein the platen flexible abrasive disk articles are selected from the group consisting of: flexible abrasive disks, flexible raised-island abrasive disks, flexible abrasive disks with resilient backing layers, flexible abrasive disks with resilient backing layers having a vacuum-seal polymer backing layer, flexible abrasive disks having attached solid abrasive pellets, chemical-mechanical planarization resilient disk pads that are suitable for use with liquid abrasive slurries, chemical-mechanical planarization resilient disk pads having nap covers, shallow- island chemical-mechanical planarization abrasive disks, shallow-island abrasive disks with resilient backing layers having a vacuum-seal polymer backing layer, and flat-surfaced slurry abrasive plate disks.

7. The machine of claim 1 where auxiliary workpiece spindles in excess of the at least three workpiece spindles, which are primary workpiece spindles, are attached to the machine base precision-flat surface and where each of the more than three auxiliary workpiece spindles are positioned between sets of two adjacent primary three -point equally spaced workpiece spindles, the auxiliary work piece spindles having spindle- tops having centers of rotation positioned on the machine base spindle-circle, and top surfaces of the spindle-tops of the auxiliary spindles are co-planar with top surfaces of the spindle-tops of the primary spindles.

8. The machine of claim 1 where the three-point fixed-spindle floating-platen is configured to abrade the flat-surfaced spindle-tops with a structure comprising: a) the at least three spindle-top flat surfaces are co-planar with each other;

b) flexible abrasive disk articles having annular bands of abrasive coated surfaces where a selected flexible abrasive disk is attached in flat conformal contact with the platen abrading surface;

c) wherein the platen can be moved vertically along the platen rotation axis by the spherical-action platen rotation device to allow the abrasive surface of the abrasive disk that is attached to the platen abrading surface to contact the top surfaces of the spindle-tops;

d) providing that the at least three spindle-tops are rotated about their respective spindle axes and the platen is rotated about the platen rotation axis to abrade the spindle-tops while the moving platen abrading surface is in force-controlled abrading pressure with the spindle-tops.

9. A process of abrading flat-surfaced workpieces using a three-point fixed-spindle floating-platen abrading machine comprising:

a) providing at least three primary rotary spindles having rotatable flat-surfaced spindle-tops with each primary rotary spindle having a spindle-top axis of rotation at a center of the rotatable flat-surfaced spindle top;

b) providing an abrading machine base having a horizontal, flat top surface and a spindle-circle where the spindle-circle is located at an approximate center of the machine base top surface and the spindle-circle is coincident with the machine base top surface;

c) providing the at least three rotary spindles at a location with approximately equal spaces between each of them, and the spindle-tops' axes of rotation intersect the machine base spindle-circle, and the spindles are attached to the machine base top surface at those spindle-circle locations;

e) providing a floating rotatable abrading platen having a flat annular abrading surface where the platen is supported by and rotationally driven about a floating platen rotation axis located at a rotational center of the floating platen by a spherical- action rotation device located at the rotational center of the floating platen and the spherical-action rotation device restrains the floating platen in a radial direction relative to the floating platen axis of rotation and the platen axis of rotation is concentric with the machine base spindle-circle;

g) configuring the spherical- action rotation device to allow spherical motion of the floating platen about the rotational center of the floating platen where the floating platen abrading surface is nominally horizontal;

h) providing flexible abrasive disk articles having annular bands of abrasive coated flat surfaces and attaching a selected flexible abrasive disk in flat conformal contact with the floating platen abrading surface wherein the attached abrasive disk is concentric with the floating platen abrading surface;

j) attaching equal-thickness workpieces having parallel or approximately parallel opposed flat surfaces to be in flat-surfaced contact with the flat surfaces of the at least three spindle-tops and the floating platen is moved vertically to allow an abrasive surface of the abrasive disk that is attached to the floating platen abrading surface to contact top surfaces of the workpieces;

k) wherein the at least three spindle-tops having the attached workpieces are rotated about respective spindles' axes and the floating platen is rotated about the floating platen rotation axis to single-side abrade the workpieces while the moving floating platen abrading surface is in force-controlled abrading pressure with the workpieces.

10. A process of abrading an abrading surface of a floating platen that is a component of a three-point fixed-spindle floating-platen abrading machine to recondition or reestablish the planar flatness of the platen abrading surface comprising:

a) providing at least three primary rotary spindles having rotatable flat- surfaced spindle-tops that have a spindle-top axis of rotation at the center of the rotatable flat- surfaced spindle top;

d) positioning the three spindle-top flat surfaces to be co-planar with each other;

e) providing a floating rotatable abrading platen having a flat annular abrading surface where the floating rotatable abrading platen is supported by and rotationally driven about a floating rotatable abrading platen rotation axis located at a rotational center of the floating rotatable abrading platen by a spherical-action rotation device located at the rotational center of the floating rotatable abrading platen, and the spherical-action rotation device restraining the floating rotatable abrading platen in a radial direction relative to the floating rotatable abrading platen axis of rotation and the floating rotatable abrading platen axis of rotation is concentric with the machine base spindle-circle; f) configuring the spherical-action rotation device to allow spherical motion of the floating rotatable abrading platen about the rotational center of the floating rotatable abrading platen where the floating rotatable abrading platen abrading surface is nominally horizontal;

g) attaching flexible abrasive disks or abrasive conditioning rings having flat-surfaced abrasive coating surfaces to the flat surfaces of the at least three spindles' spindle- tops;

h) moving the floating rotatable abrading platen vertically along the floating rotatable abrading platen rotation axis by the spherical-action platen rotation device to allow the floating rotatable abrading platen abrading surface to contact the abrasive surfaces of the attached flexible abrasive disks or the attached abrasive conditioning rings that are on the spindle-top flat surfaces of the at least three spindles;

i) rotating the at least three spindle-tops having the attached abrasive disks or attached abrasive conditioning rings about the respective spindles' axes and rotating the floating rotatable abrading platen about the floating rotatable abrading platen rotation axis to abrade the abrading-surface of the floating rotatable abrading platen with the attached abrasive disks or attached abrasive conditioning rings while the moving floating rotatable abrading platen abrading surface is in force- controlled abrading pressure with the selected abrasive disks or abrasive conditioning rings.

11. The process of claim 10 where the abrading surface of the floating rotatable abrading platen is abraded to recondition or reestablish planar flatness of the floating rotatable abrading platen abrading surface using conditioning rings where circular-shaped conditioning rings having a flat-surfaced abrasive coated annular band are attached to the at least three spindle-tops, where the conditioning rings annular abrasive surfaces have equal heights above each spindle-top wherein the at least three spindle- tops having the attached conditioning rings are rotated about the respective spindles' axes while moving the floating rotatable abrading platen abrading surface in force- controlled abrading pressure with the spindle-top conditioning rings.

12. A process of abrading an abrading surface of an abrasive disk that is attached to the abrading surface of a floating platen that is a component of a fixed-spindle floating platen abrading machine, wherein the abrading surface of the abrading platen is abraded to recondition or reestablish planar flatness of the abrading surface of the abrasive disk comprising:

a) providing at least three primary rotary spindles having rotatable flat- surfaced spindle-tops that have a spindle-top axis of rotation at a center of the rotatable flat- surfaced spindle top;

c) providing at least three rotary spindles with approximately equal spaces between each of them and the spindle-tops' axes of rotation intersect the machine base spindle-circle and the spindles are attached to the machine base top surface at those spindle-circle locations;

d) configuring the three spindle-top flat surfaces to be co-planar with each other;

e) providing a floating rotatable abrading platen having a flat annular abrading surface where the floating abrading platen is supported by and rotationally driven about a platen rotation axis located at the rotational center of the floating abrading platen by a spherical-action rotation device located at the rotational center of the floating abrading platen and the spherical-action rotation device restrains the platen in a radial direction relative to the floating abrading platen axis of rotation and the platen axis of rotation is concentric with the machine base spindle-circle;

f) providing that the spherical-action rotation device allows spherical motion of the floating abrading platen about the rotational center of the platen where the floating abrading platen abrading surface is nominally horizontal;

h) providing flexible abrasive disk articles having annular bands of abrasive coated flat surfaces where a selected flexible abrasive disk is attached in flat conformal contact with the floating abrading platen abrading surface by disk attachment techniques where the attached abrasive disk is concentric with the platen abrading surface; i) moving the platen vertically along the platen rotation axis by the spherical-action platen rotation device to allow the abrading surface of the abrasive disk that is attached to the abrading surface of the platen to contact the abrasive surfaces of the selected flexible abrasive disks or the selected abrasive conditioning rings that are attached to the spindle-top flat surfaces of the at least three spindles;

13. The process of claim 12 where the abrading surface of an abrasive disk that is attached to the abrading surface of the floating platen is abraded to recondition or reestablish the planar flatness of the abrading surface of the abrasive disk using conditioning rings where circular- shaped conditioning rings having a flat-surfaced abrasive coated annular band are attached to the at least three spindle-tops where the conditioning ring annular abrasive surfaces have equal heights above each spindle- top wherein the at least three spindle-tops having the attached conditioning rings are rotated about their respective spindles' axes while the moving abrasive surface of the abrasive disk that is attached to the abrading surface of the floating platen is in force- controlled abrading pressure with the spindle-top abrasive conditioning rings.

14. The machine of claim 1 where the three-point fixed-spindle floating-platen machine has an automated robotic workpiece loading apparatus that can selectively install and remove workpieces for the three-point fixed-spindle floating-platen abrading machine apparatus, the automated robotic workpiece loading apparatus comprising: multiple individual workpieces or workpiece carrier devices in a corresponding workpiece or workpiece carrier storage device

an automated robotic device that can sequentially transport and install selected flat workpieces or flat workpiece carrier devices on the top flat surface on all of the at least three spindle-top flat surfaces by picking selected individual workpieces or workpiece carrier devices from a corresponding workpiece or workpiece carrier storage device,

the robotic device configured to transport the selected individual workpieces or workpiece carrier devices to a select spindle spindle-top and configured to position the selected individual workpieces or workpiece carrier devices concentrically with a rotational center of the rotatable spindle-top,

wherein the workpiece or workpiece carrier device is attached to the spindle-top with vacuum for abrading action on the workpieces by the abrading machine apparatus; and

the same automated robotic device sequentially can remove selected flat workpieces or flat workpiece carrier devices from the top flat surface on all three spindle-top flat surfaces by picking the individual workpieces or workpiece carriers from a selected spindle-top and transporting them to a corresponding workpiece or workpiece carrier storage device for storage.

15. A process of loading workpieces using the apparatus of claim 14 where

workpieces are selectively installed and removed from a three-point fixed-spindle floating- platen abrading machine having: an automated robotic device that sequentially transports and installs selected flat workpieces or flat workpiece carrier devices on the top flat surface on all three spindle-top flat surfaces by picking selected individual workpieces or workpiece carrier devices from a corresponding workpiece or workpiece carrier storage device and transporting it to a select spindle spindle-top where it is positioned concentrically with the rotational center of the rotatable spindle-top wherein the workpiece or workpiece carrier is attached to the spindle-top with vacuum for abrading action on the workpieces by the abrading machine; and the same automated robotic device sequentially can remove selected flat workpieces or flat workpiece carrier devices from the top flat surface on all three spindle-top flat surfaces by picking the individual workpieces or workpiece carriers from a selected spindle-top and transporting them to a corresponding workpiece or workpiece carrier storage device for storage.

16. The machine of claim 1 where the three-point fixed-spindle floating-platen machine has an automated robotic abrasive disk loading apparatus that can selectively install and remove abrasive disks to and from a floating platen of a three-point fixed- spindle floating-platen abrading machine wherein the automated robotic device sequentially can install selected abrasive disks comprising flexible abrasive disks, flexible raised-island abrasive disks, flexible abrasive disks having attached solid abrasive pellets, chemical mechanical planarization resilient disk pads, shallow-island abrasive disks, flat- surfaced slurry abrasive plate disks and non- abrasive cloth or other material pads are selectively attached to the floating platen flat-surfaced abrading by picking selected individual abrasive disks from a corresponding abrasive disk storage device and transporting it to the floating platen abrading surface where it is positioned concentrically with the rotational center of the floating platen and the flexible abrasive disk is pressed conformably against the abrading surface of the floating platen wherein the abrasive disk is attached to the floating platen abrading surface with vacuum for abrading action on the workpieces by the abrading machine; and the same automated robotic device sequentially removes the selected abrasive disk from the flat abrading surface of the floating platen by picking the abrasive disk from the floating platen after the abrasive disk attachment vacuum is released and transporting the abrasive disk to an abrasive disk device for storage.

17. A process of using the machine of claim 16 where an automated robotic device selectively installs and removes abrasive disks to and from a floating platen of a three- point fixed-spindle floating-platen abrading machine comprising: an automated robotic device sequentially installing selected abrasive disks to the floating platen flat-surfaced abrading by picking selected individual abrasive disks from a corresponding abrasive disk storage device and transporting it to the floating platen abrading surface; positioning the selected individual abrasive disk concentrically with the rotational center of the floating platen; attaching the abrasive disk to the floating platen abrading surface with vacuum for abrading action on the workpieces by the abrading machine and the same automated robotic device removes selected abrasive disk from the flat abrading surface of the floating platen by picking the abrasive disk from the floating platen after the abrasive disk attachment vacuum is released and transporting the abrasive disk.

18. The machine of claim 1 where the at least three rotary spindles are

mechanically attached to respective at least three rotary spindle two-piece spindle-mount devices having rotary spindle two-piece spindle-mount device locking devices where rotatable spindle-mount spherical-action rotors are supported by respective stationary spindle-mount spherical-bases that are attached to a machine base wherein the spindle-top flat surfaces of the individual at least three rotary spindles can be mutually aligned to be co-planar with the other spindle-tops' flat surfaces by adjusting the spherical angle of the respective rotatable spindle-mount spherical-action rotors relative to the respective stationary spindle-mount spherical-bases while the rotatable spindle-mount spherical- action rotors are in intimate flat-surfaced contact with the flat annular abrading surface of the platen after which rotary spindle two-piece spindle-mount device' locking devices are engaged to lock the respective rotatable spindle-mount spherical-action rotors to the respective stationary spindle-mount spherical-bases to structurally maintain the co-planar alignment of the at least three spindle-tops' flat surfaces after the platen abrading surface is separated from contact with the least three rotary spindle tops.

19. A process where the machine of claim 18 is configured and aligned where the spindle-top flat surfaces of the at least three rotary spindles are mutually aligned to be co- planar with the other spindle-tops' flat surfaces by adjusting the spherical angle of the respective rotatable spindle-mount spherical-action rotors relative to the respective stationary spindle-mount spherical-bases while the rotatable spindle-mount spherical- action rotors are positioned in intimate flat-surfaced contact with the flat annular abrading surface of the platen after which the rotary spindle two-piece spindle-mount device' locking devices are engaged to lock the respective rotatable spindle-mount spherical- action rotors to the respective stationary spindle-mount spherical-bases to structurally maintain the co-planar alignment of the at least three spindle-tops' flat surfaces after the platen abrading surface is separated from contact with the least three rotary spindle tops.

20. The machine of claim 18 where each of the at least three rotary spindles has multiple paired sets of removable rotor mount tabs that are attached to the respective spindle-mount spherical-action rotors and adjacent multiple removable spherical-base tabs that are attached to the respective spindle-mount spherical-action spherical-bases where small gaps exist between the pairs of adjacent respective removable rotor mount tabs and the removable spherical-base tabs wherein a liquid adhesive can be applied in the small gap areas that exist between the pairs of adjacent respective removable rotor mount tabs and the removable spherical-base tabs after the at least three rotary spindles' spindle-tops are aligned to be co-planar with each other wherein the adhesive is solidified and structurally bonds the respective pairs of removable rotor mount tabs and the respective adjacent removable spherical-base tabs together wherein the respective spindle-mount spherical-action rotors are structurally fixtured to the respective spindle-mount spherical- action spherical-bases where the respective spindle-mount spherical-action rotors are prevented from moving relative to the respective spindle-mount spherical-action spherical- bases.

21. The process of claim 19 where each of the at least three rotary spindles has multiple paired sets of removable rotor mount tabs that are attached to the respective spindle-mount spherical-action rotors and adjacent multiple removable spherical-base tabs that are attached to the respective spindle-mount spherical-action spherical-bases where small gaps exist between the pairs of adjacent respective removable rotor mount tabs and the removable spherical-base tabs wherein a liquid adhesive can be applied in the small gap areas that exist between the pairs of adjacent respective removable rotor mount tabs and the removable spherical-base tabs after the at least three rotary spindles' spindle-tops are aligned to be co-planar with each other wherein the adhesive is solidified and structurally bonds the respective pairs of removable rotor mount tabs and the respective adjacent removable spherical-base tabs together wherein the respective spindle-mount spherical-action rotors are structurally fixtured to the respective spindle-mount spherical- action spherical-bases where the respective spindle-mount spherical-action rotors are prevented from moving relative to the respective spindle-mount spherical-action spherical- bases.