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Publication numberUS3504457 A
Publication typeGrant
Publication date7 Apr 1970
Filing date5 Jul 1966
Priority date5 Jul 1966
Also published asDE1652046A1
Publication numberUS 3504457 A, US 3504457A, US-A-3504457, US3504457 A, US3504457A
InventorsHans R Jacobsen, Elmer W Jensen
Original AssigneeGeoscience Instr Corp
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Polishing apparatus
US 3504457 A
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Description  (OCR text may contain errors)

April 7, 1970 H, R, JACOBSEN ET AL 3,504,457

POLISHING APPARATUS Filed July 5, 1966 40W iy//5/ BEAR/NG CON 754C 7' (IRG/N6 MF4/V5 INVENTORS HANS REM/#0107' .fS/V B52/.MER M JENSEN 2@ @Mge ys.

United States Patent O York Filed July 5, 1966, Ser. No. 562,757 Int. Cl. B24b 5/00, 29/00, 11/00 U.S. Cl. 51-131 4 Claims ABSTRACT OF THE DISCLOSURE A device for polishing semiconductor wafers wherein the polishing tool comprises a poromeric material of polyurethane reinforced with a polyester and with a polishing slurry thereon is urged into contact with the workpiece.

This invention relates to an apparatus for processing workpieces and, more specifically for imparting a polished finish to elements subjected thereto.

Many applications of present day interest require thin, fragile semiconductor wafers having a highly polished critical surface. To produce such a finish, prior art organizations have rotated such semiconductor elements against a lapping substrate in the presence of a polishing slurry.

The surface of the lapping plate in contact with the semiconductor elements has typically included thereon -as the active polishing member a pitch composition, papers, pseudo papers or other nonwovens, or felt substances. However, the above and other prior art operative polishing surfaces are characterized by at least several of the following deficiencies: (1) temperature sensitivity, and therefore instability at high polishing rates; (2) unhomogeneous consistency; (3) a propensity to pick up and retain foreign elements; (4) poor wear characteristics requiring frequent replacement; (5) variations from sample to sample; (6) the characteristics of being impermeable, and thereby preventing a polishing slurry from reaching all surface areas of a product being operated upon; (7) relatively little tensile strength, thereby being subject to distortion; and (8) a resistance to bonding, thereby being difiicult to affix to cooperating compositions and/or a lapping plate.

It is therefore an object of the present invention to provide an improved apparatus for polishing workpieces.

More specifically, an object of the present invention is the provision of a resilient, homogeneous polishing organization which is porous, relatively insensitive to temperature, and which may be fabricated with little variation from sample to sample.

These and other objects of the present invention are realized in a specific illustrative polishing organization which comprises a layer of Corfam (a trademark of the Du Pont Corporation for a poromeric material) afiixed to a lapping substrate via layers of an adhesive, chemically inert nitrile rubber, and a pressure sensitive, clean release adhesive. A pororneric material, such as Du Ponts Corfam, comprises polyurethane reinforced with polyester. In this regard see, for example, Chemistry of Organic Compounds by C. R. Noller, published by W. B. Saunders Company in 1965, at chapter 36.

The active, or free Corfam surface is adapted to be fiat such that the surface of the work elements brought into rotational bearing contact therewith will be polished, i.e., will be rendered flat. In an alternative embodiment of the present invention a porous film e.g., of foam polyurethane, is attached to the Corfam to function as the active polishing surface.

A complete understanding of the present invention and of the above and other objects thereof may be gained 3,504,457 Patented Apr. 7, 1970 from a consideration of an illustrative embodiment thereof depicted in the accompanying drawing.

Referring now to the drawing, there is shown in crosssectional form an illustrative polishing organization which embodies the principles of the present invention. The arrangement includes a layer of Corfam 20 which has a layer 35 of a, chemically inert material, eg., nitrile rubber, afiixed thereto by an adhesive 30. A layer 40` of a pressure sensitive, clean release adhesive 40 is bonded to the bottom of the nitrile rubber layer 35 for purposes of facilitating the attachment and removal of the composite polishing laminated structure with respect to a metal lapping substrate 45. It is noted that other poromeric materials, as well as other compositions embodying the attributes of Corfam described herein, may be employed in place of the Corfam layer 20.

The Corfam layer 20 is fabricated such that the upper surface thereof exhibits the requisite flatness required for a particular polishing operation (assuming that a fiat surface is desired for the workpiece), Employing such a layer 20,the lapping substrate 45 is urged into a bearing pressure contact with elements 15 to be polished. Such elements 15 may comprise, for example, semiconductor wafers, with these elements being shown in the drawing as mounted on a rotating mounting block 10. Further, the polishing operation may advantageously take place in a polishing liquid slurry environment, with the slurry being supplied by a slurry source 50 via a nozzle 51.

The Corfam material 20 is very porous, and hence the slurry is translated by the layer 20 to all portions of the surface of the elements 15 thereby effecting uniform polishing. Also, the Corfam material 20 is essentially insensitive to temperature, at least in the temperature range of interest for polishing operations. Accordingly, polishing may be accomplished at high rates of speed. Further, the layer 20 is homogeneous, and may be fabricated in relatively large quantities to produce many uniform polishing layers without material variation from element to element.

Moreover, Corfam is resilient and prevents damage to elements 15 being polished by absorbing mechanical vibrations and any compaction caused by overshoot of the mounting members 10 or 45. In addition, the layer 20 is durable which is beneficial from maintenance and batch processing rate standpoints.

Still further, the active, upper surface of the Corfam layer 20 can be treated or impregnated when required for special polishing operations. Such treatment may comprise, for example, brushing, napping, skiving or texturing the polishing Corfam surface to increase the number for active polishing fibers, or calendering the surface to increase its atness.

The composite laminated polishing organization 20-30- 35-40 is easily attached to, and removed from the lapping substrate 45 by reason of the properties of the pressure sensitive, clean release adhesive layer 40. The inert layer 35 is employed to insulate the adhesive 40 from the layers thereabove, and also from the slurry which would otherwise reach the adhesive I40 through the porous Corfam layer 20. Such lforeign substances would tend to change the physical state of the adhesive 40, e.g., harden it thereby making attachment to and removal from the plate 45 more difficult.

By way of -functional operation, when rotational bearing contact is established between the Corfam upper surface and the lwork pieces 15, the desired polishing surface is imparted to the lower, critical surface of these elements. Hence, the desired polishing is accomplished.

In an alternative embodiment of the invention a porous film 23, e.g., of foam polyurethane, is afiixed to the upper surface of the Corfam layer 20 by a porous adhesive 25. In such an arrangement, the upper face of the film 23 is the effective polishing surface, with the Corfam backing layer 20 providing resiliency and strength, while maintaining a composite porous organization which is desirable in a polishing organization for the reasons given hereinabove. Thus it is noted that compositions 4which are porous only in film thicknesses, but which otherwise have desirable polishing properties, may be used as a polishing surface when mounted on a Corfam backing layer 20.

Thus, the organization shown in the drawing, both with and without the film 23 and the adhesive 25, has been shown by the above to function as a very desirable polishing structure.

1t is to be understood that the above described method and organizations are only illustrative of the application of the principles of the present inventions. Numerous other arrangements and modes of operation may be devised by those skilled in the art without departing from the spirit and scope of this invention. For example, the active polishing surface, i.e., the upper surface of the Corfam 20 or the lm 23 if such a lm is employed, may exhibit a geometry other than a at plane -when a nonat work piece of a corresponding geometry is to be polished. In addition, other known bonding mechanisms, such as mechanical interlocking or distortion, may be used to fabricate the composite laminated polishing structure shown in the drawing vwithout the use of the adhesives 25 and 30.

We claim:

1. In combination in a polishing organization, a poromeric material comprising polyurethane reinforced with polyester, a porous film axed to said poromeric material, wherein said poromeric material has rst and second surfaces, said rst surface engaging said porous hlm, and further comprising an inert layer of nitrile rubber I affixed to said second surface of said Corfam.

plate, and means for selectively urging work pieces to be polished into a bearing relationship with said lapping plate.

3. In combination in a polishing organization, a poromeric material comprising polyurethane reinforced with polyester, a porous hlm aixed to said poromeric material, Iwherein said porous lm is polyurethane, and means for selectively urging work pieces to be polished into bearing contact with said porous film.

4. In combination in a polishing organization, a lapping substrate, a poromeric layer comprising polyurethane reinforced with polyester mounted on said substrate, said poromeric layer including a polishing surface thereon, and means for urging work pieces to be polished into bearing contact with said poromeric polishing surface.

References Cited UNITED STATES PATENTS 2,644,280 7 l 95 3 ONeil 51-406 3,050,909 8/ 1962 Rawstron 51-124 3,082,582 3/1963 Jeske 51-407 X 3,123,953 3/1964 Merkl 51-283 3,360,889 1/1968 Borish 51-131 X 671,130 4/1901 Darden 51-401 804,853 11/1905 Ireson. 1,923,719 8/1933 Fuller 51-301 X 2,650,158 8/1953 Eastman 51-407 X FOREIGN PATENTS 681,832 3/1964 Canada.

OTHER REFERENCES Boot and 'Shoe Recorder, Oct. l, 1963, article titled The Story of Corfam pages 1-2 thereof.

HAROLD D. WHITEHEAD, Primary Examiner U.'S. C1. XR.

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US671130 *2 May 19002 Apr 1901Newton J DardenPencil-sharpener.
US804853 *17 Mar 190521 Nov 1905Charles L IresonMethod of attachment of rubber and leather.
US1923719 *27 Apr 193122 Aug 1933Gen ElectricStropping material
US2644280 *13 Sep 19507 Jul 1953Carborundum CoSanding disk accessory
US2650158 *3 Aug 195025 Aug 1953Carborundum CoScouring implement
US3050909 *16 Feb 196028 Aug 1962Rawstron George OrmerodApparatus for and method of polishing aspheric surfaces
US3082582 *21 Jul 196026 Mar 1963Formax Mfg CorpSanding pad assembly
US3123953 *13 Dec 196210 Mar 1964 merkl
US3360889 *11 Oct 19652 Jan 1968Indiana Contact Lens IncMethod for altering the power of a corneal contact lens
CA681832A *10 Mar 1964Dominion Rubber CoFlexible laminate
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3841031 *30 Oct 197215 Oct 1974Monsanto CoProcess for polishing thin elements
US3857123 *27 Oct 197231 Dec 1974Monsanto CoApparatus for waxless polishing of thin wafers
US3947953 *23 Aug 19746 Apr 1976Nitto Electric Industrial Co., Ltd.Method of making plastic sealed cavity molded type semi-conductor devices
US4728552 *6 Jul 19841 Mar 1988Rodel, Inc.Substrate containing fibers of predetermined orientation and process of making the same
US4841680 *20 Sep 198827 Jun 1989Rodel, Inc.Inverted cell pad material for grinding, lapping, shaping and polishing
US4927432 *25 Mar 198622 May 1990Rodel, Inc.Pad material for grinding, lapping and polishing
US4954141 *25 Jan 19894 Sep 1990Showa Denko Kabushiki KaishaPolishing pad for semiconductor wafers
US5257478 *31 Jan 19922 Nov 1993Rodel, Inc.Apparatus for interlayer planarization of semiconductor material
US5403228 *8 Jul 19934 Apr 1995Lsi Logic CorporationTechniques for assembling polishing pads for silicon wafer polishing
US5510175 *1 Mar 199523 Apr 1996Chiyoda Co., Ltd.Polishing cloth
US5618227 *5 Sep 19958 Apr 1997Mitsubushi Materials CorporationApparatus for polishing wafer
US5649855 *23 Jan 199622 Jul 1997Nec CorporationWafer polishing device
US5664989 *18 Jul 19969 Sep 1997Kabushiki Kaisha ToshibaPolishing pad, polishing apparatus and polishing method
US5692950 *8 Aug 19962 Dec 1997Minnesota Mining And Manufacturing CompanyAbrasive construction for semiconductor wafer modification
US5769699 *19 May 199523 Jun 1998Motorola, Inc.Polishing pad for chemical-mechanical polishing of a semiconductor substrate
US5846335 *22 Apr 19978 Dec 1998Ebara CorporationMethod for cleaning workpiece
US5913712 *12 Mar 199722 Jun 1999Cypress Semiconductor Corp.Scratch reduction in semiconductor circuit fabrication using chemical-mechanical polishing
US6007407 *20 Aug 199728 Dec 1999Exclusive Design Company, Inc.Abrasive construction for semiconductor wafer modification
US6036579 *12 Jan 199814 Mar 2000Rodel Inc.Polymeric polishing pad having photolithographically induced surface patterns(s) and methods relating thereto
US6095902 *23 Sep 19981 Aug 2000Rodel Holdings, Inc.Polyether-polyester polyurethane polishing pads and related methods
US6210254 *2 Feb 20003 Apr 2001Rodel Holdings Inc.Method of manufacturing a polymeric polishing pad having photolithographically induced surface pattern(s)
US623859210 Mar 199929 May 20013M Innovative Properties CompanyWorking liquids and methods for modifying structured wafers suited for semiconductor fabrication
US628411424 Mar 20004 Sep 2001Rodel Holdings Inc.Method of fabricating a porous polymeric material by electrophoretic deposition
US633684512 Nov 19978 Jan 2002Lam Research CorporationMethod and apparatus for polishing semiconductor wafers
US641638522 Jun 20019 Jul 2002Lam Research CorporationMethod and apparatus for polishing semiconductor wafers
US643195920 Dec 199913 Aug 2002Lam Research CorporationSystem and method of defect optimization for chemical mechanical planarization of polysilicon
US651741822 Jun 200111 Feb 2003Lam Research CorporationMethod of transporting a semiconductor wafer in a wafer polishing system
US662674021 Dec 200030 Sep 2003Rodel Holdings, Inc.Self-leveling pads and methods relating thereto
US6746311 *24 Jan 20008 Jun 20043M Innovative Properties CompanyPolishing pad with release layer
US684897424 Sep 20021 Feb 2005Jsr CorporationPolishing pad for semiconductor wafer and polishing process using thereof
US685202022 Jan 20038 Feb 2005Raytech Innovative Solutions, Inc.Polishing pad for use in chemicalómechanical planarization of semiconductor wafers and method of making same
US68637741 Mar 20028 Mar 2005Raytech Innovative Solutions, Inc.Polishing pad for use in chemical-mechanical planarization of semiconductor wafers and method of making same
US688415617 Jun 200326 Apr 2005Cabot Microelectronics CorporationMulti-layer polishing pad material for CMP
US702566818 Jun 200311 Apr 2006Raytech Innovative Solutions, LlcGradient polishing pad made from paper-making fibers for use in chemical/mechanical planarization of wafers
US703718422 Jan 20032 May 2006Raytech Innovation Solutions, LlcPolishing pad for use in chemical-mechanical planarization of semiconductor wafers and method of making same
US719234028 Nov 200120 Mar 2007Toyo Tire & Rubber Co., Ltd.Polishing pad, method of producing the same, and cushion layer for polishing pad
US725563710 Oct 200114 Aug 2007Applied Materials, Inc.Carrier head vibration damping
US73291702 Mar 200612 Feb 2008Toyo Tire & Rubber Co., Ltd.Method of producing polishing pad
US7331847 *17 Jan 200619 Feb 2008Applied Materials, IncVibration damping in chemical mechanical polishing system
US743516125 Apr 200514 Oct 2008Cabot Microelectronics CorporationMulti-layer polishing pad material for CMP
US749776728 Jan 20053 Mar 2009Applied Materials, Inc.Vibration damping during chemical mechanical polishing
US761852925 May 200417 Nov 2009Rohm And Haas Electronic Materials Cmp Holdings, IncPolishing pad for electrochemical mechanical polishing
US76415402 Mar 20065 Jan 2010Toyo Tire & Rubber Co., LtdPolishing pad and cushion layer for polishing pad
US76548851 Oct 20042 Feb 2010Applied Materials, Inc.Multi-layer polishing pad
US77628702 Mar 200627 Jul 2010Toyo Tire & Rubber Co., LtdPolishing pad and cushion layer for polishing pad
US780703814 Sep 20095 Oct 2010Rohm And Haas Electronic Materials Cmp Holdings, Inc.Method for electrochemical mechanical polishing
US806655226 Jan 200529 Nov 2011Applied Materials, Inc.Multi-layer polishing pad for low-pressure polishing
US80753721 Sep 200413 Dec 2011Cabot Microelectronics CorporationPolishing pad with microporous regions
US809270715 Aug 200710 Jan 20123M Innovative Properties CompanyCompositions and methods for modifying a surface suited for semiconductor fabrication
US837681310 Feb 201019 Feb 2013Applied Materials, Inc.Retaining ring and articles for carrier head
US853512115 Feb 201317 Sep 2013Applied Materials, Inc.Retaining ring and articles for carrier head
US20110269380 *13 Aug 20103 Nov 2011Iv Technologies Co., Ltd.Base layer, polishing pad including the same and polishing method
EP0291100A2 *16 May 198817 Nov 1988Asahi Kasei Kogyo Kabushiki KaishaPolishing cloth
EP0304645A2 *26 Jul 19881 Mar 1989Rodel, Inc.Inverted cell pad material for grinding, lapping, shaping and polishing
EP0555660A2 *18 Jan 199318 Aug 1993Westech, Inc.Apparatus for interlayer planarization of semiconductor material
EP1295680A2 *24 Sep 200226 Mar 2003JSR CorporationPolishing pad for semiconductor wafer
WO1991014538A1 *22 Mar 19913 Oct 1991Westech Systems IncApparatus for interlayer planarization of semiconductor material
Classifications
U.S. Classification451/288, 257/E21.237, 451/533
International ClassificationB24B37/04, H01L21/304, B24D7/02
Cooperative ClassificationB24B37/042, B24B37/22, H01L21/02024, B24D7/02
European ClassificationB24B37/22, B24D7/02, B24B37/04B, H01L21/02D2M2P