US20150118944A1

US20150118944A1 - Polishing apparatus, method for attaching polishing pad, and method for replacing polishing pad

Info

Publication number: US20150118944A1
Application number: US14/372,446
Authority: US
Inventors: Ryuichi Kosuge; Tadakazu Sone; Soichi Isobe; Takeshi Sakurai; Eiji Hirai; Kaoru Hamaura; Suguru Ogura
Original assignee: Ebara Corp
Current assignee: Ebara Corp
Priority date: 2013-01-31
Filing date: 2014-01-29
Publication date: 2015-04-30
Also published as: CN104968472A; TW201436939A; TWI607499B; KR20150114382A

Abstract

The work of replacing a polishing pad is easily performed, and thermal damage is prevented from occurring in a polishing table. A polishing apparatus 100 includes a polishing table 110 having an attachment surface 110 a to which a polishing pad 108 used to polish a substrate 102 is attached. The polishing apparatus 100 also includes a silicone layer 111 provided on the attachment surface 110 a of the polishing table 110 and interposed between the polishing table 110 and the polishing pad 108. By interposing the silicone layer 111, it is possible to easily detach and attach the polishing pad 108. In addition, since a heat treatment for coating the silicone layer 111 on the polishing table 110 is performed at a relatively low temperature, it is possible to prevent thermal damage from occurring in the polishing table 110 due to the heat treatment.

Description

TECHNICAL FIELD

The present invention relates to a polishing apparatus, a method for attaching a polishing pad, and a method for replacing the polishing pad.

BACKGROUND ART

In recent years, a polishing apparatus is used in order to polish a surface of a substrate, such as a semiconductor wafer. The polishing apparatus polishes the surface of the substrate, while rotating a polishing table to which a polishing pad used to polish the substrate is attached, by pressing the substrate held with a top ring against the polishing pad.
In this type of polishing apparatus, the polishing pad is treated as a consumable and replaced periodically. In general, the polishing pad is replaced manually.
In an attachment process of attaching the polishing pad to the polishing table, the polishing pad the rear surface of which is an adhesive surface is manually attached to the polishing table by an operator. The polishing pad is attached to the polishing table with an adhesive force strong to some degree, so that the pad does not become displaced when the substrate is polished. Accordingly, the polishing pad is difficult to detach in a detachment process of detaching the polishing pad from the polishing table, thus taking time in detachment work.
In addition, if air is caught between the polishing pad and the polishing table and thus pockets of trapped air are produced in the attachment process, adverse effects may be exerted on the polishing performance profile of the substrate. If the polishing pad is strongly bonded to the polishing table at this point, it is difficult to temporarily detach the polishing pad and reuse the pad. Accordingly, if pockets of trapped air are produced between the polishing pad and the polishing table, this polishing pad may be detached and a new polishing pad may be attached in some cases. This is not preferable, however, from the viewpoint of economic efficiency.
On the other hand, it is known in conventional techniques to interpose a layer of fluorine-based resin between a polishing table and the adhesive surface of a polishing pad. These techniques are considered to allow the polishing pad attached to the polishing table to be easily detached from the polishing table.
Polishing pads are generally cut out so as to be conformal in shape to the attachment surface of a polishing table and attached thereto. A polishing pad therefore has no beginning ends with which to begin detaching the polishing pad in a detachment process of detaching the polishing pad from the polishing table. Accordingly, the polishing pad has the problem of taking time in detachment work.
In contrast, it is known that in conventional techniques, a polishing pad is cut out, so that part thereof protrudes outward from a polishing table, and the polishing pad is detached using this protruding part as a beginning end. It is also known to detach a polishing pad using a take-up jig, thereby saving labor in the detachment of the polishing pad.

CITATION LIST

Patent Literature

Patent Literature 1: Japanese Patent Laid-Open No. 2008-238375
Patent Literature 2: Japanese Patent Laid-Open No. 2007-20339
Patent Literature 3: Japanese Patent Laid-Open No. 10-217148

SUMMARY OF INVENTION

Technical Problem

In conventional techniques, however, no consideration is given to the possibility of thermal damage occurring in the polishing table due to heat treatment at the time of attaching the polishing pad to the polishing table.
That is, in conventional techniques, the layer of fluorine-based resin is interposed between the polishing table and the adhesive surface of the polishing pad. Hence, it is assumed that in order to coat the fluorine-based resin on the polishing table, a heat treatment needs to be performed at such a relatively high temperature as 300° C. to 400° C.
The polishing table can be formed from various materials. If the polishing table is formed from a material, such as resin, relatively low in allowable temperature limit, thermal damage, such as deformation, may occur in the polishing table due to the heat treatment for coating fluorine-based resin.
Hence, an object of the present invention is to realize a polishing apparatus and a method for attaching a polishing pad whereby it is possible to easily perform the work of replacing the polishing pad and prevent thermal damage from occurring in a polishing table.
Conventional techniques give no consideration either to precise replacement of the polishing pad in which effects exerted by the substrate on polishing performance are suppressed.
That is, in conventional techniques in which a beginning end protruding from the polishing table is previously formed in the polishing pad, this beginning end may serve as a singular point and affect polishing performance.
Even if a conventional technique in which the polishing pad is detached using a take-up jig is used, there is, after all, the need for a beginning end with which to begin detaching the polishing pad. The conventional technique therefore may damage or break a surface of the polishing table at the time of taking up the polishing pad.
Since the polishing pad is bonded to the polishing table with a certain degree of adhesive force, so that the polishing pad does not peel off from the polishing table during polishing, considerable force is required to detach the polishing pad.
On the other hand, in an attachment process of attaching the polishing pad to the polishing table, the polishing pad the rear surface of which is an adhesive surface is, in general, manually attached to the polishing table. Here in the attachment process, pockets of trapped air may be produced between a surface of the polishing table and the rear surface of the polishing pad. In that case, it is difficult to remove the pockets of trapped air even if the polishing pad is pressed so as to even out the polishing pad from the front surface side thereof. The polishing pad therefore has to be detached and discarded and a new polishing pad has to be attached once again. In addition, verification as to whether pockets of trapped air are produced depends on the human tactual or visual sense. Accordingly, it is difficult to precisely judge the quality of the state of attachment.
Hence, another object of the present invention is to realize precise replacement of a polishing pad in which effects exerted by a substrate on polishing performance are suppressed.
Yet another object of the present invention is to suppress effects exerted by a substrate on polishing performance and save labor in the work of detaching a polishing pad.

Solution to Problem

A polishing apparatus of an embodiment of the present invention, which has been devised in view of the above-described objects, includes a polishing table having an attachment surface to which a polishing pad used to polish a substrate is attached; and a silicone layer provided on the attachment surface of the polishing table and interposed between the polishing table and the polishing pad.
The silicone layer may include a silicone resin-containing adhesive agent coated on the attachment surface or a silicone resin-containing adhesive sheet bonded to the attachment surface.
The silicone layer may also include resin-based paint prepared by mixing ceramic with silicon and coated on the attachment surface.
The polishing table may be formed by containing at least one of silicon carbide, stainless steel, resin, and aluminum oxide.
The polishing apparatus may further include an adhesive agent of the polishing pad interposed between the silicone layer and the polishing pad.
The polishing apparatus may be further provided with a control unit for pressurizing or depressurizing a rear surface of the polishing pad attached to the polishing table, the rear surface being a side of the polishing pad opposite to its polishing surface, wherein the control unit may pressurize the rear surface of the polishing pad in a detachment process of detaching the polishing pad from the polishing table or may pressurize or depressurize the rear surface of the polishing pad in an attachment process of attaching the polishing pad to the polishing table.
The polishing apparatus may be further provided with a pressing member for pressing the rear surface of the polishing pad in the detachment process of detaching the polishing pad from the polishing table, wherein the pressing member may include a piston disposed in a hole formed in the attachment surface of the polishing table to which the polishing pad is attached; and a driving member capable of driving the piston in a direction in which the rear surface of the polishing pad is pressed in the detachment process.
A method for attaching a polishing pad of an embodiment of the present invention includes the steps of providing a silicone layer on an attachment surface of a polishing table having the attachment surface to which the polishing pad used to polish a substrate is attached; heat-treating the silicone layer provided on the attachment surface; and attaching the polishing pad onto the heat-treated silicone layer.
A method for replacing a polishing pad of an embodiment of the present invention includes the step of pressurizing a rear surface of the polishing pad attached to the polishing table in the detachment process of detaching the polishing pad from the polishing table, the rear surface being a side of the polishing pad opposite to its polishing surface, or pressurizing or depressurizing the rear surface of the polishing pad in the attachment process of attaching the polishing pad to the polishing table in the above-described method for attaching the polishing pad or in the method for detaching the polishing pad from the polishing table.
In the process of detaching the polishing pad, the piston disposed in a hole formed in the attachment surface of the polishing table to which the polishing pad is attached can be driven in a direction in which the rear surface of the polishing pad is pressed.

Advantageous Effects of Invention

According to an embodiment of the present invention described above, it is possible to easily perform the work of replacing a polishing pad and prevent thermal damage from occurring in a polishing table.
Also according to an embodiment of the present invention described above, it is possible to realize precise replacement of a polishing pad in which effects exerted by a substrate on polishing performance are suppressed.
Also according to an embodiment of the present invention described above, it is possible to suppress effects exerted by a substrate on polishing performance and save labor in the work of detaching a polishing pad.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a drawing schematically illustrating the overall configuration of a polishing apparatus of a first embodiment.

FIG. 2 is a drawing illustrating a mode of adhesion between a polishing pad and a polishing table.

FIG. 3 is a drawing illustrating a flow of the process of attaching a polishing pad and a polishing process.

FIG. 4 is a drawing schematically illustrating the overall configuration of a polishing apparatus of a second embodiment.

FIG. 5 is a drawing schematically illustrating the detailed peripheral configuration of a polishing table.

FIG. 6 is a drawing illustrating, by way of example, array patterns of a plurality of holes formed in a polishing table.

FIG. 7 is a drawing illustrating a flow of the process of detaching a polishing pad.

FIG. 8 is a drawing schematically illustrating the way the process of detaching the polishing pad is carried out.

FIG. 9 is a drawing illustrating a flow of the process of attaching a polishing pad.

FIG. 10 is a drawing schematically illustrating the way the process of attaching the polishing pad is carried out.

FIG. 11 is a drawing schematically illustrating the overall configuration of a polishing apparatus.

FIG. 12 is a drawing schematically illustrating a polishing apparatus of a third embodiment.

FIG. 13 is a drawing illustrating details on a pressing member.

FIG. 14 is a drawing illustrating another example of the pressing member.

FIG. 15 is a drawing schematically illustrating the way the process of detaching the polishing pad is carried out.

FIG. 16 is a drawing schematically illustrating a polishing apparatus of a fourth embodiment.

FIG. 17 is a drawing schematically illustrating a polishing apparatus of a fifth embodiment.

DESCRIPTION OF EMBODIMENTS

First Embodiment

Hereinafter, a polishing apparatus and a method for replacing a polishing pad in accordance with a first embodiment of the present invention will be described according to the accompanying drawings. In the embodiment to be discussed hereinafter, a CMP (Chemical Mechanical Polishing) polishing apparatus will be described by way of example, though the embodiment is not limited to this apparatus.
FIG. 1 is a drawing schematically illustrating the overall configuration of the polishing apparatus of the first embodiment. As illustrated in FIG. 1, a polishing apparatus 100 is provided with a polishing table 110 the upper surface of which can be fitted with a polishing pad 108 used to polish a substrate 102, such as a semiconductor wafer; a first electric motor 112 for rotary-driving the polishing table 110; a top ring 116 capable of holding the substrate 102; and a second electric motor 118 for rotary-driving the top ring 116.
The polishing apparatus 100 is also provided with a slurry line 120 for supplying a polishing agent-containing abrasive liquid to the upper surface of the polishing pad 108; and a dresser unit 124 provided with a dresser disk 122 for performing the conditioning (dressing) of the polishing pad 108.
When the substrate 102 is polished, the polishing agent-containing abrasive liquid is supplied from the slurry line 120 to the upper surface of the polishing pad 108, and the polishing table 110 is rotary-driven by the first electric motor 112. Then, the substrate 102 held on the top ring 116 is pressed against the polishing pad 108 with the top ring 116 being rotated around a rotational axis decentered from the rotational axis of the polishing table 110. Consequently, the substrate 102 is polished and planarized by the polishing pad 108.
Next, a mode of adhesion between the polishing pad 108 and the polishing table 110 will be described. FIG. 2 is a drawing illustrating a mode of adhesion between the polishing pad and the polishing table. As illustrated in FIG. 2, in the present embodiment, an adhesive agent-containing adhesive surface 109 of the polishing pad is formed on a rear surface 108 b on the opposite side of a polishing surface 108 a of the polishing pad 108. In addition, a silicone layer 111 is provided on an attachment surface 110 a of the polishing table 110 to which the polishing pad 108 is attached. In other words, the silicone layer 111 is interposed between the polishing table 110 and the polishing pad 108, and the adhesive surface 109 is interposed between the silicone layer 111 and the polishing pad 108.
The silicone layer 111 may include a silicone resin-containing adhesive agent coated on the attachment surface 110 a of the polishing table 110. In this case, the silicone resin-containing adhesive agent can be coated on the attachment surface 110 a of the polishing table 110 by various methods, including brush coating, roller coating, blast coating and spray coating.
The silicone layer 111 may also include a silicone resin-containing adhesive sheet bonded to the attachment surface 10 a of the polishing table 110.
The silicone layer 111 may also include resin-based paint prepared by mixing ceramic (for example, ceramic powder) with silicone and coated on the attachment surface 110 a of the polishing table 110. In this case, the resin-based paint prepared by mixing ceramic with silicon can be coated on the attachment surface 110 a of the polishing table 110 by various methods, including brush coating, roller coating, blast coating and spray coating. Mixing ceramic with silicone increases the hardness of the silicone layer 111 and can thus improve the durability thereof.
The polishing table 110 may be formed by containing at least one of such materials as silicon carbide (SiC), stainless steel (SUS), resin, and aluminum oxide (alumina).
Next, a description will be made of a process of attaching the polishing pad and a polishing process of the present embodiment. FIG. 3 is a drawing illustrating a flow of the process of attaching the polishing pad and the polishing process. In FIG. 3, a discussion will be made by taking an example in which a silicone resin adhesive agent is used as one illustrative embodiment of the silicone layer 111.
As illustrated in FIG. 3, an attachment process is first carried out by coating a silicone adhesive agent on a surface (attachment surface 110 a) of the polishing table 110 (step S101). Then, the attachment process is carried out by heat-treating the silicone adhesive agent coated on the polishing table 110 (step S102). This heat treatment applies a heat of, for example, approximately 150° C. to 200° C. to, for example, the polishing table 110 and the silicone adhesive agent as a whole. By this heat treatment, the silicone adhesive agent is favorably coated on the attachment surface 110 a of the polishing table 110.
Subsequently, the attachment process is carried out by attaching the polishing pad 108 onto the heat-treated silicone adhesive agent (step S103). Note that an adhesive surface 109 is previously coated on the rear surface 108 b of the polishing pad 108 and, in step S103, the adhesive surface 109 of the polishing pad 108 is attached onto the silicone adhesive agent. Consequently, the process of attaching the polishing pad 108 is completed.
Subsequently, the polishing process is carried out by rotating the first electric motor 112 (step S104), thereby rotating the polishing table 110. Then, the polishing process is carried out by rotating the second electric motor 118 (step S105), thereby rotating the top ring 116.
Then, the polishing process is carried out by pressing the substrate 102 held on the top ring 116 against the polishing surface 108 a of the polishing pad 108 to polish a surface of the substrate 102 (step S106). Subsequently, the polishing process is carried by determining whether or not the polishing of the substrate 102 is completed (step S107). The determination as to whether or not the polishing of the substrate 102 is completed can be made on the basis of, for example, a change in the torque current of the first electric motor 112 or the second electric motor 118.
In the polishing process, a polishing treatment is repeated until the determination is made that the polishing of the substrate 102 is completed, if the polishing of the substrate 102 is determined to be not yet completed (No in step S107). On the other hand, the polishing treatment is completed in the polishing process if the polishing of the substrate 102 is determined to be completed (Yes in step S107).
As described above, according to the present embodiment, it is possible to easily perform the work of replacing the polishing pad 108 and prevent thermal damage from occurring in the polishing table 110.
That is, in the present embodiment, the silicone layer 111 is interposed between the attachment surface 110 a of the polishing table 110 and the polishing pad 108 (or the adhesive surface 109). Consequently, the adherence of the polishing pad 108 (adhesive surface 109) to the polishing table 110 is weakened for a direction intersecting at right angles with the attachment surface 110 a.
Accordingly, it is possible to easily detach the polishing pad 108 in the process of, for example, detaching the polishing pad 108, if the polishing pad 108 is peeled off in the direction intersecting at right angles with the attachment surface 110 a. In addition, adhesive force in the shear direction of the polishing pad 108 (direction along the attachment surface 110 a) is kept strong by attaching the polishing pad 108 to the polishing table 110 with the silicone layer 111 interposed therebetween. As a result, it is possible to prevent the polishing pad 108 from peeling off or becoming displaced during the polishing of the substrate 102.
This polishing pad 108 can be easily peeled off even if pockets of trapped air are produced between the polishing table 110 and the polishing pad 108 in the process of attaching the polishing pad 108. Accordingly, it is possible to temporarily detach the polishing pad 108 and easily reattach the pad.
Yet additionally, according to the present embodiment, it is possible to prevent thermal damage, such as deformation, from occurring in the polishing table 110 due to the heat treatment of the silicone layer 111, since the silicone layer 111 is used.
That is, considering a case in which a layer of fluorine-based resin is interposed between the polishing table and the polishing pad as a comparative example, it is assumed that in order to coat the fluorine-based resin on the polishing table, a heat treatment needs to be performed at such a relatively high temperature as 300° C. to 400° C. If the heat treatment is performed at such a relatively high temperature, thermal damage, such as deformation, may occur in the polishing table in a case where the polishing table is formed from such a material as resin relatively low in allowable temperature limit.
In contrast, according to the present embodiment, a heat treatment for coating the silicone layer 111 on the polishing table 110 can be performed at such a relatively low temperature as approximately 150° C. to 200° C. since the silicone layer 111 is interposed between the polishing table 110 and the polishing pad 108. Accordingly, it is possible to prevent thermal damage, such as deformation, from occurring in the polishing table 110 due to heat treatment, even if the polishing table 110 is formed from such a material as resin relatively low in allowable temperature limit. Also according to the present embodiment, the same peel strength (ease of detachment) of the polishing pad 108 as in a case where fluorine-based resin is heat-treated at such a relatively high temperature as 300° C. to 400° C. can be obtained, even if the silicone layer 111 is heat-treated at such a relatively low temperature as approximately 150° C. to 200° C.
Yet additionally, the silicone layer 111, since being superior in chemical and heat resistance, can withstand not only the temperature rise of an abrasive liquid supplied from the slurry line 120 during polishing but also the temperature rise of the polishing table 110 during polishing.
The planarity of the polishing table 110 affects the polishing process performance of the substrate 102. Since the silicone layer 111 can be thinly coated to a thickness of, for example, 10±5 μm, it is possible to maintain the planarity of the polishing table 110.
If the silicone layer 111 is formed using resin-based paint prepared by mixing ceramic with silicon, the hardness of the silicone layer 111 can be increased by the mixture of ceramic with silicone. As a result, it is possible to improve the durability of the silicone layer 111.

Second Embodiment

Hereinafter, a polishing apparatus and a method for replacing a polishing pad in accordance with a second embodiment of the present invention will be described according to the accompanying drawings. In the embodiment to be discussed hereinafter, a CMP (Chemical Mechanical Polishing) polishing apparatus will be described by way of example, though the embodiment is not limited to this apparatus. Note that the polishing apparatus and the method for replacing a polishing pad according to the second embodiment can be embodied in combination with the polishing apparatus and the method for replacing the polishing pad according to the above-described first embodiment.
FIG. 4 is a drawing schematically illustrating the overall configuration of the polishing apparatus of the second embodiment. As illustrated in FIG. 4, a polishing apparatus 1100 is provided with a polishing table 1110 the upper surface of which can be fitted with a polishing pad 1108 used to polish a substrate 1102, such as a semiconductor wafer; a first electric motor 1112 for rotary-driving the polishing table 1110; a top ring 1116 capable of holding the substrate 1102; and a second electric motor 1118 for rotary-driving the top ring 1116.
The polishing apparatus 1100 is also provided with a slurry line 1120 for supplying a polishing agent-containing abrasive liquid to the upper surface of the polishing pad 1108; and a dresser unit 1124 provided with a dresser disk 1122 for performing the conditioning (dressing) of the polishing pad 1108.
The polishing apparatus 1100 is also provided with an operating panel 1130 for inputting various operation commands related to the replacement of the polishing pad 1108 and outputting various information related to the replacement of the polishing pad 1108; and a control unit 1140 for controlling each component of the polishing apparatus 1100. The control unit 1140 is a controller used to pressurize or depressurize the rear surface on the opposite side of the polishing surface of the polishing pad 1108 attached to the polishing table 1110. The control unit 1140 pressurizes the rear surface of the polishing pad 1108 in the detachment process of detaching the polishing pad 1108 from the polishing table 1110. In addition, the control unit 1140 pressurizes or depressurizes the rear surface of the polishing pad 1108 in the attachment process of attaching the polishing pad 1108 to the polishing table 1110. Specific control modes of the control unit 1140 will be described later.
The polishing apparatus 1100 is also provided with a rotary joint 1160 used to take a fluid in and out between each a compressed-air line 1152 and a vacuum line 1154 within the polishing apparatus 1100 and the polishing table 1110; and a rotary connector 1170 used to input and output signals between the control unit 1140 and the polishing table 1110. Pressure regulators 1156-1 and 1156-2 are disposed in the compressed-air line 1152 and the vacuum line 1154, respectively. In addition, a pressurization valve 1158-1 and an adsorption valve 1158-2 used to open or close the lines are disposed in the compressed-air line 1152 and the vacuum line 1154, respectively. The pressure regulator 1156-1 is an electropneumatic regulator used to control the pressure of air injected from the compressed-air line 1152 to, for example, a high pressure or a low pressure. The pressure regulator 1156-2 is a manually-operated regulator used to control the pressure of air sucked into the vacuum line 1154 to, for example, a high pressure or a low pressure. Note that the pressure regulator 1156-1 is not limited to an electropneumatic regulator. Likewise, the pressure regulator 1156-2 is not limited to a manually-operated regulator.
When the substrate 1102 is polished, a polishing agent-containing abrasive liquid is supplied from the slurry line 1120 to the upper surface of the polishing pad 1108, and the polishing table 1110 is rotary-driven by the first electric motor 1112. Then, the substrate 1102 held on the top ring 1116 is pressed against the polishing pad 1108 with the top ring 1116 being rotated around a rotational axis decentered from the rotational axis of the polishing table 1110. Consequently, the substrate 1102 is polished and planarized by the polishing pad 1108.
FIG. 5 is a drawing schematically illustrating the detailed peripheral configuration of the polishing table. As illustrated in FIG. 5, a plurality of holes 1111 penetrating through the attachment surface 1110 a to which the polishing pad 1108 is attached and the surface 1110 b on the opposite side of the attachment surface 1110 a is formed in the polishing table 1110. The holes 1111 are one example of communication passages for communicating the rear surface 1108 b on the opposite side of the polishing surface 1108 a of the polishing pad 1108 with the outer portions of the polishing table 1110. The communication passages are not limited to holes but may be any means for communicating the rear surface 1108 b of the polishing pad 1108 with the outer portions of the polishing table 1110.
As also illustrated in FIG. 5, air (fluid) supplied from the compressed-air line 1152 is injected into the plurality of holes 1111 formed in the polishing table 1110 through conduction paths 1159 when the pressurization valve 1158-1 is open and the adsorption valve 1158-2 is closed. On the other hand, air is sucked from the plurality of holes 1111 into the vacuum line 1154 through the conduction paths 1159 when the pressurization valve 1158-1 is closed and the adsorption valve 1158-2 is open.
The control unit 1140 pressurizes the rear surface 1108 b of the polishing pad 1108 in a detachment process by blowing a fluid (air) onto the rear surface 1108 b of the polishing pad 1108 through the holes 1111. In addition, the control unit 1140 pressurizes the rear surface 1108 b of the polishing pad 1108 in an attachment process by blowing a fluid (air) onto the rear surface 1108 b of the polishing pad 1108 through the holes 1111, or depressurizes the rear surface 1108 b of the polishing pad 1108 (rear surface 1108 b side) by sucking the fluid from the rear surface 1108 b of the polishing pad 1108 through the holes 1111. Note that depressurizing the rear surface 1108 b of the polishing pad 1108 means reducing a pressure applied to the rear surface 1108 b.
A pressure sensor 1182 and a solenoid valve 1184 for opening or closing a conduction path 1159 are disposed in each of the conduction paths 1159 connecting the plurality of holes 1111 with the compressed-air line 1152 and the vacuum line 1154. A pressure detected by the pressure sensor 1182 is input to the control unit 1140 through the rotary connector 1170. The solenoid valve 1184 is opened or closed on the basis of a control signal input from the control unit 1140 through the rotary connector 1170.
Next, a description will be made of array patterns of the plurality of holes 1111 formed in the polishing table 1110. FIG. 6 is a drawing illustrating, by way of example, array patterns of the plurality of holes 1111 formed in the polishing table 1110. As illustrated in FIG. 6( a), the plurality of holes 1111 may be vorticosely disposed in the polishing table 1110 from the center toward the outer circumference of the polishing table. Alternatively, as illustrated in FIG. 6( b), the plurality of holes 1111 may be concentrically disposed in the polishing table 1110. Yet alternatively, as illustrated in FIG. 6( c), the plurality of holes 1111 may be disposed into a lattice-like shape in the polishing table 1110.
Note that an adhesive agent is coated on the rear surface of polishing pad 1108 and the polishing pad 1108 is attached to the polishing table 1110 with the adhesive agent. Here, as illustrated in FIG. 6( b), it is possible to facilitate the detachment of the polishing pad 1108 without impairing the retaining force of the polishing pad 1108 based on the adhesive agent, by performing coating (nonadhesive agent) in which the adhesive agent is not applied to the vicinity of the holes 1111 of the polishing table 1110.
Next, a description will be made of the process of detaching the polishing pad 1108. FIG. 7 is a drawing illustrating a flow of the process of detaching the polishing pad. FIG. 8 is a drawing schematically illustrating the way the process of detaching the polishing pad is carried out.
As illustrated in FIG. 7, the command “pressurize” for detaching the polishing pad 1108 is first issued from the operating panel 130 in the process of detaching the polishing pad 1108. Then, the control unit 1140 outputs valve switchover signals to the pressurization valve 1158-1 and the adsorption valve 1158-2. Consequently, the pressurization valve 1158-1 and the adsorption valve 1158-2 are switched over to the “pressurize” mode. Specifically, the pressurization valve 1158-1 is set to “open” and the adsorption valve 1158-2 is set to “close.”
The control unit 1140 performs pressure setting on the pressure regulator 1156-1. Specifically, the control unit sets the pressure regulator 1156-1 to “high pressure.” Here, the high pressure means a pressure at which the polishing pad 1108 is detached or becomes easy to detach.
Subsequently, the control unit 1140 performs the open/close-control of the solenoid valve. For example, the control unit 1140 sets the plurality of solenoid valves 1184 associated with the plurality of holes 1111 to “open,” according to the programmed order.
Specifically, as illustrated in FIG. 8( a), the control unit 1140 first sets a solenoid valve 1184, among the plurality of solenoid valves 1184, associated with a hole 1111 (for example, a first hole 1111 a in FIG. 6( b)) in the peripheral edge of the polishing table 1110 to “open.” The control unit 1140 thus blows air onto the rear surface 1108 b of the polishing pad 1108 through the opened solenoid valve 1184 and pressurizes the rear surface. As a result, the peripheral edge of the polishing pad 1108 is peeled off or becomes easy to peel off. Accordingly, it is possible to easily create a beginning end 1109 used to detach the polishing pad 1108.
A pressure sensor 1182 disposed in a conduction path 1159 through which air is injected measures the pressure of this conduction path 1159, i.e., the pressure of the hole 1111 into which air is injected, with air being injected into the hole 1111 in the peripheral edge of the polishing table 1110. The control unit 1140 determines the state of attachment of the polishing pad 1108 on the basis of the pressure measured by the pressure sensor 1182.
Specifically, if the control unit 1140 detects that the pressure measured by the pressure sensor 1182 is below a preset threshold pressure, the control unit 1140 determines that a portion of the polishing pad 1108 at this hole has peeled off. That is, the pressure of the hole 1111 rises if air is injected under the condition of the polishing pad 1108 being not peeled off. The pressure of the hole 1111 drops, however, if the polishing pad 1108 is peeled off, since air escapes from that hole. If the control unit 1140 determines that the polishing pad 1108 is peeled off, the control unit 1140 sets the solenoid valve 1184 associated with the hole 1111 the pressure of which has dropped to “close.”
By injecting air into the holes 1111 in the peripheral edge of the polishing table 1110 and pressurizing the rear surface of the polishing pad 1108 as described above, an operator can catch hold of the beginning end 1109 and detach the polishing pad 1108, as illustrated in FIG. 8( b).
After the beginning end 1109 is created, the polishing pad 1108 can be detached manually. In this example, however, a description will be made of a case in which further assistance is provided in the detachment of the polishing pad 1108. If a program is in progress, the control unit 1140 opens a solenoid valve 1184 associated with another hole 1111 (for example, a second hole 1111 b in FIG. 6( b)) adjacent to a hole 1111 (for example, the first hole 1111 a in FIG. 6( b)) into which air is injected first, and injects air into the hole 1111 b.
Then, the polishing pad 1108 is detached or becomes easy to detach, as illustrated in FIG. 8( c), due to the pressurization of the rear surface 1108 b of the polishing pad 1108 by air injection. The operator can therefore easily detach the polishing pad 1108.
The pressures of other holes 1111 into which air is injected are measured in the same way as described above. If a pressure drop is detected in any of the holes 1111, a solenoid valve 1184 associated with this hole 1111 is closed. In addition, the same process as described above is also performed on other holes 1111 adjacent to the above-mentioned holes 1111. By repeating the work of detaching the polishing pad 1108 and pressurization from the adjacent holes 1111 as illustrated in FIGS. 8( d) and 8(e), it is possible to easily detach the polishing pad 1108. Note that the control unit 1140 can inject air in order, for example, from the holes 1111 in the peripheral edge of the polishing table 1110 to the holes 1111 adjacent to the abovementioned holes 1111. As an alternative method, air may be injected into all of the holes at the same pressure from the beginning, and solenoid valves associated with holes in which pressure drops are detected may be closed in succession.
When the polishing pad 1108 is detached completely, the command “end” of the detachment of the polishing pad is issued through the operating panel 1130. Then, the control unit 1140 determines that the program has terminated, and outputs a valve switchover signal to the pressurization valve 1158-1. Consequently, the pressurization valve 1158-1 is set to “close” and the process of detaching the polishing pad 1108 is completed.
Next, a description will be made of a process of attaching the polishing pad 1108. FIG. 9 is a drawing illustrating a flow of the process of attaching the polishing pad. FIG. 10 is a drawing schematically illustrating the way the process of attaching the polishing pad is carried out.
First, the work of attaching the polishing pad 1108 is performed by an operator. This is the work in which the operator manually attaches a bonding surface on the backside of the polishing pad 1108 to the polishing table 1110 in an orderly manner, as illustrated in FIG. 10( a).
When the work of attaching the polishing pad 1108 is finished, the command “suction” of the polishing pad 1108 is issued from the operating panel 1130. Then, the control unit 1140 outputs valve switchover signals to the pressurization valve 1158-1 and the adsorption valve 1158-2. Consequently, the pressurization valve 1158-1 and the adsorption valve 1158-2 are switched over to the “suction” mode. Specifically, the pressurization valve 1158-1 is set to “close” and the adsorption valve 1158-2 is set to “open.”
Subsequently, the control unit 1140 performs the open/close-control of the solenoid valves. Specifically, the control unit 1140 sets all of the solenoid valves 1184 associated with the plurality of holes 1111 to “open.” Consequently, air is sucked from all of the holes 1111 formed in the polishing table 1110.
As a result, even if a pocket of trapped air 1107 is produced between the rear surface 1108 b of the polishing pad 1108 and the attachment surface 1110 a of the polishing table 1110 in the work of attaching the polishing pad 1108, as illustrated in FIG. 10( b), it is possible to remove the pocket of trapped air 1107 by sucking air from this pocket of trapped air 1107, as illustrated in FIG. 10( c). Note that although an example is shown here in which air is sucked from all of the holes 1111, the present embodiment is not limited to this example. For example, air may be sucked from at least one of holes 1111 associated with a location where the pocket of trapped air 1107 is produced.
When the suction of the pocket of trapped air 1107 is finished, the control unit 1140 temporarily sets all of the solenoid valves 1184 associated with the plurality of holes 1111 to “close.” Then, the control unit 1140 outputs a valve switchover signal to the adsorption valve 1158-2. Consequently, the adsorption valve 1158-2 is switched over to the “pressurize” mode. Specifically, the adsorption valve 1158-2 is set to “close.”
Subsequently, the control unit 1140 performs pressure setting on the pressure regulator 1156-1. Specifically, the control unit 1140 sets the pressure regulator 1156-1 to “low pressure.” Here, the low pressure means a pressure at which the polishing pad 1108 is not detached or does not become easy to detach. The reason for setting the pressure regulator 1156-1 to “low pressure” is that the correctly-attached polishing pad 1108 is detached or becomes easy to detach at high pressures.
Then, the control unit 1140 outputs a valve switchover signal to the pressurization valve 1158-1. Consequently, the pressurization valve 1158-1 is switched over to the “pressurize” mode. Specifically, the pressurization valve 1158-1 is set to “open.”
Subsequently, the control unit 1140 sets all of the solenoid valves 1184 associated with the plurality of holes 1111 to “open.” Consequently, air is injected from all of the holes 1111 formed in the polishing table 1110 and is blown onto the rear surface 1108 b of the polishing pad 1108, as illustrated in FIG. 10( d).
The pressure sensors 1182 disposed in the conduction paths 1159 measure the pressures of the conduction paths 1159, i.e., the pressures of the holes 1111 into which air is injected, with air being injected into all of the holes 1111 in the peripheral edge of the polishing table 1110. The control unit 1140 determines the state of attachment of the polishing pad 1108 on the basis of the pressures measured by the pressure sensors 1182.
Specifically, if the control unit 1140 detects that any of the pressures measured by the pressure sensors 1182 is lower than a preset threshold pressure or that the rise time of any of the measured pressures is longer than a preset threshold time, the control unit 1140 determines that the state of attachment of the polishing pad is abnormal, for example, that a certain portion of the polishing pad 1108 is peeled off or a pocket of trapped air is produced.
That is, the pressure being measured does not rise even though air is injected, if the polishing pad 1108 is peeled off. In addition, a time required for the pressure to rise is prolonged, compared with a case where any pockets of trapped air 1107 are not produced, if a pocket of trapped air 1107 is produced. If the control unit 1140 determines that the state of attachment of the polishing pad 1108 is abnormal, the control unit 1140 shows on the operating panel 1130 that the attachment of the polishing pad 1108 is “abnormal.”
On the other hand, if the control unit 1140 determines that the state of attachment of the polishing pad 1108 is normal, the control unit 1140 shows on the operating panel 1130 that the attachment of the polishing pad 1108 is “normal.” Then, the control unit 1140 sets all of the solenoid valves 1184 associated with the plurality of holes 1111 to “close.”
Consequently, if any failure is present in the attachment of the polishing pad 1108, the operator can notice this failure at an early stage immediately after attachment work.
Note that in the present embodiment, the pressure sensors 1182 are individually disposed for all of the plurality of holes 1111. Accordingly, it is possible to specify where a failure has occurred, if the failure is present in the state of attachment of the polishing pad 1108. Note however that it is possible to adjust the number of holes 1111, as appropriate, for which pressure sensors 1182 are arranged by, for example, disposing one pressure sensor 1182 for every two holes 1111 or for every four holes 1111, rather than individually disposing the pressure sensors 1182 for the respective holes 1111. Alternatively, one pressure sensor 1182 may be disposed for all of the holes 1111. Also in the present embodiment, an example has been shown in which the state of attachment of the polishing pad 1108 is determined by injecting air into all of the plurality of holes 1111. Without limitation to this method, however, it is also possible to inject air into at least one of the holes 1111 to determine the state of attachment of the polishing pad 1108 at this location. Also in the present embodiment, an example has been shown in which each of the plurality of holes 1111 penetrates through the polishing table 1110, and each of the conduction paths 1195 is connected to each of the holes 1111. Without limitation to this configuration, however, the plurality of holes 1111 may be, for example, integrated into one hole within the polishing table 1110 and made open on the rear surface side of the polishing table 1110. Then, this hole may be connected to one conduction path 1195.
Thereafter, when the command “end” of the attachment of the polishing pad is issued through the operating panel 1130, the control unit 1140 outputs a valve switchover signal to the pressurization valve 1158-1. Consequently, the pressurization valve 1158-1 is set to “close” and the process of attaching the polishing pad 1108 is completed.
As described above, according to the present embodiment, the rear surface 1108 b of the polishing pad 1108 is pressurized in the process of detaching the polishing pad 1108. Consequently, it is possible to make the polishing pad 1108 easy to detach without affecting the polishing performance of a substrate. Also according to the present embodiment, the rear surface 1108 b of the polishing pad 1108 is depressurized in the process of attaching the polishing pad 1108. Consequently, even if pockets of trapped air 1107 are produced in the polishing pad 1108, these pockets of trapped air 1107 can be sucked and removed. Also according to the present embodiment, it is possible to determine the state of attachment of the polishing pad 1108, such as lift or peel-off, by pressurizing the rear surface 1108 b of the polishing pad 1108 and monitoring a pressure rise time and a pressure distribution in the process of attaching the polishing pad 1108. As a result, according to the present embodiment, it is possible to realize precise replacement of the polishing pad 1108 in which effects exerted by a substrate on polishing performance are suppressed.

Third to Fifth Embodiments

Hereinafter, polishing apparatuses and methods for detaching a polishing pad in accordance with third to fifth embodiments of the present invention will be described according to the accompanying drawings. In the embodiments to be discussed hereinafter, a CMP (Chemical Mechanical Polishing) polishing apparatus will be described by way of example, though the embodiments are not limited to this apparatus. Note that the polishing apparatuses and the methods for detaching a polishing pad according to the third to fifth embodiments can be embodied in combination with the polishing apparatus and the method for replacing the polishing pad according to the above-described first embodiment.

Third Embodiment

FIG. 11 is a drawing schematically illustrating the overall configuration of a polishing apparatus. As illustrated in FIG. 11, a polishing apparatus 2100 is provided with a polishing table 2110 the upper surface of which can be fitted with a polishing pad 2108 used to polish a substrate 2102, such as a semiconductor wafer; a first electric motor 2112 for rotary-driving the polishing table 2110: a top ring 2116 capable of holding the substrate 2102; and a second electric motor 2118 for rotary-driving the top ring 2116.
The polishing apparatus 2100 is also provided with a slurry line 2120 for supplying a polishing agent-containing abrasive liquid to the upper surface of the polishing pad 2108; and a dresser unit 2124 including a dresser disk 2122 for performing the conditioning (dressing) of the polishing pad 2108.
The polishing apparatus 2100 is also provided with an operating panel 2130 for inputting various operation commands related to the detachment of the polishing pad 2108 and outputting various information related to the detachment of the polishing pad 2108; and a control unit 2140 for controlling each component of the polishing apparatus 2100.
The control unit 2140 is a controller used to press a rear surface 2108 b on the opposite side of the polishing surface of the polishing pad 2108 attached to the polishing table 2110 in the detachment process of detaching the polishing pad 2108 from the polishing table 2110.
The polishing apparatus 2100 is also provided with rotary joints 2160 and 2170 used to take a fluid in and out between a compressed-air line 2152 and a later-described pressing member 2200 within the polishing apparatus 2100. The compressed-air line 2152 is branched into two compressed-air lines 2152-1 and 2152-2. The compressed-air lines 2152-1 and 2152-2 are connected to the rotary joints 2160 and 2170, respectively. A pressure regulator 2156 is disposed in the compressed-air line 2152. Valves 2158-1 and 2158-2 used to open or close the lines are disposed in the compressed-air lines 2152-1 and 2152-2, respectively. The pressure regulator 2156 is an electropneumatic regulator used to control the pressure of air injected from the compressed-air line 2152 to, for example, a high pressure or a low pressure. Note that the pressure regulator 2156 is not limited to an electropneumatic regulator.
When the substrate 2102 is polished, a polishing agent-containing abrasive liquid is supplied from the slurry line 2120 to the upper surface of the polishing pad 2108, and the polishing table 2110 is rotary-driven by the first electric motor 2112. Then, the substrate 2102 held on the top ring 2116 is pressed against the polishing pad 2108 with the top ring 2116 being rotated around a rotational axis decentered from the rotational axis of the polishing table 2110. Consequently, the substrate 2102 is polished and planarized by the polishing pad 2108.
FIG. 12 is a drawing schematically illustrating the polishing apparatus of the third embodiment. FIG. 13 is a drawing illustrating details on the pressing member. As illustrated in FIGS. 12 and 13, a hole 2111 is formed in the attachment surface 2110 a of the polishing table 2110 to which the polishing pad 2108 is attached. Specifically, a hole (communication passage) 2111 communicating the attachment surface 2110 a to which the polishing pad 2108 is attached with a surface (the rear surface 2110 b of the polishing table 2110 in the present embodiment) other than the attachment surface 2110 a is formed in the polishing table 2110.
A pressing member 2200 for pressing the rear surface 2108 b on the opposite side of the polishing surface of the polishing pad 2108 in the detachment process of detaching the polishing pad 2108 from the polishing table 2110 is disposed on the rear surface side of the polishing table 2110.
The pressing member 2200 is provided with a piston 2210 disposed in the hole 2111, and a driving member 2220 capable of driving the piston 2210 in a direction in which the rear surface 2108 b of the polishing pad 2108 is pressed in the detachment process. The driving member 2220 is housed in an enclosure 2230 mounted on the rear surface side of the polishing table 2110. The piston 2210 has a pressing surface 2210 a for pressing the rear surface 2108 b of the polishing pad 2108 in the detachment process.
The pressing member 2200 is also provided with a stopper member 2240 for restricting the movement of the piston 2210 when the piston 2210 moves in a direction toward the rear surface 2110 b of the polishing table 2110 (in a direction in which the piston 2210 moves away from the rear surface 2108 b of the polishing pad 2108). Specifically, the stopper member 2240 includes a cylindrical portion 2240-a, and a flange portion 2240-b protruding outward from one end of the cylindrical portion 2240-a.
The pressing member 2200 is also provided with a shim member 2250 for adjusting the position of the stopper member 2240, so that the pressing surface 2210 a of the piston 2210 and the attachment surface 2110 a of the polishing table 2110 are flush with each other under the condition of the piston 2210 being restricted in movement by the stopper member 2240.
Specifically, the shim member 2250 is formed into a disc-like shape, and a hole is formed in the center of the disc. The stopper member 2240 is fitted on the polishing table 2110 as the result of the other end of the cylindrical portion 2240-a being inserted into the hole 2111 through the hole of the shim member 2250 and the flange portion 2240-b being fixed to the rear surface 2110 b of the polishing table 2110 through the shim member 2250 with screws 242.
When the piston 2210 moves in the direction toward the rear surface 2110 b of the polishing table 2110, the piston 2210 is restricted in movement as the result of abutting on the other end of the cylindrical portion 2240-a. The pressing member 2200 enables the pressing surface 2210 a of the piston 2210 and the attachment surface 2110 a of the polishing table 2110 to be made flush with each other by adjusting the thickness of the shim member 2250 under the condition of the piston 2210 being restricted in movement by the stopper member 2240.
The driving member 2220 is provided with a cylinder 2260 in which first and second communicating ports 2260 a and 2260 b capable of letting a fluid (air or the like) flow therein or thereout are formed, and a partitioning member 2270. The partitioning member 2270 is used to partition between a first space 2262 communicated with the first communicating port 2260 a within the cylinder 2260 and a second space 2264 communicated with the second communicating port 2260 b within the cylinder 2260. The driving member 2220 is also provided with a coupling member 2280 for coupling the partitioning member 2270 and the piston 2210 with each other.
The driving member 2220 includes a fluid cylinder for driving the piston 2210 in a direction in which the piston abuts on or moves away from the rear surface 2108 b of the polishing pad 2108 by means of fluid inflow into or fluid outflow from the first and second communicating ports 2260 a and 2260 b. The driving member 2220 is not limited to the fluid cylinder, however. The driving member 2220 may be any means capable of driving the piston in the direction in which the rear surface 2108 b of the polishing pad 2108 is pressed in the detachment process. In the present embodiment, an example has been shown in which one pressing member 2200 is disposed for the polishing apparatus 2100. Without limitation to this configuration, however, a plurality of pressing members 2200 may be disposed.
In FIGS. 12 and 13, an example has been shown in which the cylinder 2260 is disposed externally to the polishing table 2110. The present embodiment is not limited to this configuration, however. FIG. 14 is a drawing illustrating another example of the pressing member. As illustrated in FIG. 14, the cylinder 2260 may be formed of part of the hole 2111 formed in the polishing table 2110. According to this configuration, there is no need to mount the enclosure 2230 on the rear surface side of the polishing table 2110. Thus, it is possible to form the pressing member 2200 in a compact manner.
As illustrated in FIG. 12, the compressed-air lines 2152-1 and 2152-2 are connected to the first and second communicating ports 2260 a and 2260 b, respectively, through the rotary joints 2160 and 2170. A speed control valve 2182 used to adjust the speed at which the piston 2210 goes up is disposed in the compressed-air line 2152-1. In addition, a speed control valve 2184 used to adjust the speed at which the piston 2210 goes down, and a speed control valve 2186 used to prevent the piston 2210 from abruptly jumping out of the polishing table are disposed in the compressed-air line 2152-2.
Next, a description will be made of the behavior of the pressing member 2200 in the process of detaching the polishing pad 2108. FIG. 15 is a drawing schematically illustrating the way the process of detaching the polishing pad is carried out. The upper view of FIG. 15 illustrates the state of the pressing member 2200 when the polishing apparatus 2100 is in ordinary use, rather than in a detachment process, whereas the lower view of FIG. 15 illustrates the state of the pressing member 2200 in the detachment process.
When the polishing apparatus 2100 is in ordinary use, the pressing member 2200 pressurizes the piston 2210 downward, as illustrated in the upper view of FIG. 15, as the result of air being flowed in from the first communicating port 2260 a through the compressed-air line 2152-1. Specifically, the control unit 2140 controls the valve 2158-1 to “open (air supply)” and the valve 2158-2 to “close (exhaust).” Consequently, the partitioning member 2270 is pushed downward, and therefore, the piston 2210 is also pushed downward in conjunction with the motion of the partitioning member 2270. The piston 2210 thus pushed downward goes into a state of abutting on the stopper member 2240.
On the other hand, the pressing member 2200 pressurizes the piston 2210 upward in the detachment process, as illustrated in the lower view of FIG. 15, as the result of air being flowed in from the first communicating port 2260 b through the compressed-air line 2152-2. Specifically, the control unit 2140 controls the valve 2158-1 to “close (exhaust)” and the valve 2158-2 to “open (air supply).” Consequently, the partitioning member 2270 is pushed upward, and therefore, the piston 2210 is also pushed upward in conjunction with the motion of the partitioning member 2270. The piston 2210 thus pushed upward presses the rear surface 2108 b of the polishing pad 2108 to detach the polishing pad 2108.
According to the present embodiment, it is possible to suppress adverse effects exerted on the polishing performance of the substrate 2102 and save labor in the work of detaching the polishing pad 2108. That is, according to the present embodiment, it is possible to easily detach the polishing pad 2108 since the work of detaching the polishing pad 2108 is assisted by the pressing force of the piston 2210, as illustrated in the lower view of FIG. 15. In addition, in the present embodiment, there is no need to previously form any beginning ends protruding out of the polishing table in the polishing pad or peel off the polishing pad using a take-up jig. As a result, it is possible to suppress adverse effects exerted on the polishing performance of the substrate 2102 and save labor in the work of detaching the polishing pad 2108.

Fourth Embodiment

Next, a description will be made of a polishing apparatus of a fourth embodiment. FIG. 16 is a drawing schematically illustrating the polishing apparatus of the fourth embodiment. The fourth embodiment differs from the third embodiment in that control signals for controlling the opening/closure of the valves 2158-1 and 2158-2 is input to the valves 2158-1 and 2158-2 through a rotary connector. Constituent elements the same as those of the third embodiment will therefore be excluded from the description.
As illustrated in FIG. 16, the compressed-air line 2152 is connected to a rotary joint 2160 and, after being passed therethrough, branches into two compressed-air lines 2152-1 and 2152-2. Valves 2158-1 and 2158-2 used to open or close the lines are disposed in the compressed-air lines 2152-1 and 2152-2, respectively.
On the other hand, a control signal line 2192 through which control signals for controlling the opening/closure of the valves 2158-1 and 2158-2 are transferred is input to a rotary connector 2190, and connected to the valves 2158-1 and 2158-2 through the rotary connector 2190.
When the polishing apparatus 2100 is in ordinary use, the control unit 2140 controls the valve 2158-1 to “open (air supply)” and the valve 2158-2 to “close (exhaust).” Consequently, the partitioning member 2270 is pushed downward, and therefore, the piston 2210 is also pushed downward in conjunction with the motion of the partitioning member 2270. The piston 2210 thus pushed downward goes into a state of abutting on the stopper member 2240.
On the other hand, the control unit 2140 controls the valve 2158-1 to “close (exhaust)” and the valve 2158-2 to “open (air supply)” in the detachment process. Consequently, the partitioning member 2270 is pushed upward, and therefore, the piston 2210 is also pushed upward in conjunction with the motion of the partitioning member 2270. The piston 2210 thus pushed upward presses the rear surface 2108 b of the polishing pad 2108 to detach the polishing pad 2108.
According to the present embodiment, it is possible to suppress adverse effects exerted on the polishing performance of the substrate 2102 and save labor in the work of detaching the polishing pad 2108, as in the third embodiment. That is, according to the fourth embodiment, it is possible to easily detach the polishing pad 2108 since the work of detaching the polishing pad 2108 is assisted by the pressing force of the piston 2210. In addition, in the present embodiment, there is no need to previously form any beginning ends protruding out of the polishing table in the polishing pad or peel off the polishing pad using a take-up jig. As a result, it is possible to suppress adverse effects exerted on the polishing performance of the substrate 2102 and save labor in the work of detaching the polishing pad 2108.

Fifth Embodiment

Next, a description will be made of a polishing apparatus of a fifth embodiment. FIG. 17 is a drawing schematically illustrating the polishing apparatus of the fifth embodiment. The fifth embodiment differs from the third and fourth embodiments in that a jig for detaching a polishing pad is fitted on the polishing apparatus 2100 (pressing member 2200) and used each time a detachment process is carried out. Constituent elements the same as those of the third embodiment will therefore be excluded from the description.
As illustrated in FIG. 17, a jig for detaching a polishing pad 2300 is provided with a compressed-air connection port 2302 connected to a source of compressed-air supply disposed externally to the polishing apparatus 2100, and compressed-air lines 2304-1 and 2340-2 for conveying compressed air supplied from the compressed-air connection port 2302.
A valve 2306 used to open or close the compressed-air line 2304-1 and a speed control valve 2312 used to adjust the speed at which the piston 2210 goes up are disposed in the compressed-air line 2304-1. In addition, a valve 2308 used to open or close the compressed-air line 2304-2, a speed control valve 2314 used to adjust the speed at which the piston 2210 goes down, and a speed control valve 2316 used to prevent the piston 2210 from abruptly jumping out of the polishing table are disposed in the compressed-air line 2304-2.
In addition, a jig connection port 2322 communicated with the first space 2262 and a jig connection port 2324 communicated with the second space 2264 are connected to the cylinder 2260. When a process of detaching the polishing pad 2108 is carried out, the compressed-air line 2304-1 of the jig for detaching the polishing pad 2300 is connected to the jig connection port 2322 and the compressed-air line 2304-2 is connected to the jig connection port 2324 by an operator.
When the polishing apparatus 2100 is in ordinary use, the control unit 2140 controls the valve 2306 to “open” and the valve 2308 to “close.” Consequently, the partitioning member 2270 is pushed downward, and therefore, the piston 2210 is also pushed downward in conjunction with the motion of the partitioning member 2270. The piston 2210 thus pushed downward goes into a state of abutting on the stopper member 2240.
On the other hand, the control unit 2140 controls the valve 2306 to “close” and the valve 2308 to “open” in the detachment process. Consequently, the partitioning member 2270 is pushed upward, and therefore, the piston 2210 is also pushed upward in conjunction with the motion of the partitioning member 2270. The piston 2210 thus pushed upward presses the rear surface 2108 b of the polishing pad 2108 to detach the polishing pad 2108.
According to the present embodiment, it is possible to suppress adverse effects exerted on the polishing performance of the substrate 2102 and save labor in the work of detaching the polishing pad 2108, as in the third embodiment. That is, according to the fifth embodiment, it is possible to easily detach the polishing pad 2108 since the work of detaching the polishing pad 2108 is assisted by the pressing force of the piston 2210. In addition, in the present embodiment, there is no need to previously form any beginning ends protruding out of the polishing table in the polishing pad or peel off the polishing pad using a take-up jig. As a result, it is possible to suppress adverse effects exerted on the polishing performance of the substrate 2102 and save labor in the work of detaching the polishing pad 2108.

REFERENCE SIGNS LIST

- 100 Polishing apparatus
- 102 Substrate
- 108 Polishing pad
- 108 a Polishing surface
- 108 b Rear surface
- 109 Adhesive surface
- 110 Polishing table
- 110 a Attachment surface
- 111 Silicone layer
- 1100 Polishing apparatus
- 1102 Substrate
- 1107 Pocket of trapped air
- 1108 Polishing pad
- 1108 a Polishing surface
- 1108 b Rear surface
- 1109 Beginning end
- 1110 Polishing table
- 1110 a Attachment surface
- 1110 b Surface on the opposite side of attachment surface
- 1111 Hole
- 1130 Operating panel
- 1140 Control unit
- 1152 Compressed-air line
- 1154 Vacuum line
- 1159 Conduction path
- 1160 Rotary joint
- 1170 Rotary connector
- 1182 Pressure sensor
- 2100 Polishing apparatus
- 2102 Substrate
- 2108 Polishing pad
- 2108 b Rear surface
- 2110 Polishing table
- 2110 a Attachment surface
- 2110 b Rear surface
- 2111 Hole
- 2152 Compressed-air line
- 2158-1, 2158-2 Valve
- 2200 Pressing member
- 2210 Piston
- 2210 a Abutting surface
- 2220 Driving member
- 2240 Stopper member
- 2240-a Cylindrical portion
- 2240-b Flange portion
- 2250 Shim member
- 2260 Cylinder
- 2260 a First communicating port
- 2260 b Second communicating port
- 2262 First space
- 2264 Second space
- 2270 Partitioning member
- 280 Coupling member

Claims

1. A polishing apparatus comprising:

a polishing table having an attachment surface to which a polishing pad used to polish a substrate is attached; and

a silicone layer provided on the attachment surface of the polishing table and interposed between the polishing table and the polishing pad.

2. The polishing apparatus according to claim 1, wherein the silicone layer includes a silicone resin-containing adhesive agent coated on the attachment surface or a silicone resin-containing adhesive sheet bonded to the attachment surface.

3. The polishing apparatus according to claim 1, wherein the silicone layer includes resin-based paint prepared by mixing ceramic with silicon and coated on the attachment surface.

4. The polishing apparatus according to claim 1, wherein the polishing table is formed by containing at least one of silicon carbide, stainless steel, resin, and aluminum oxide.

5. The polishing apparatus according to claim 1, further comprising an adhesive agent of the polishing pad interposed between the silicone layer and the polishing pad.

6. The polishing apparatus according to claim 1, further comprising a control unit configured to pressurize or depressurize a rear surface of the polishing pad attached to the polishing table, the rear surface being a side of the polishing pad opposite to its polishing surface, wherein the control unit pressurizes the rear surface of the polishing pad in a detachment process of detaching the polishing pad from the polishing table, or pressurizes or depressurizes the rear surface of the polishing pad in an attachment process of attaching the polishing pad to the polishing table.

7. The polishing apparatus according to claim 1, further comprising a pressing member configured to press the rear surface of the polishing pad in the detachment process of detaching the polishing pad from the polishing table, wherein the pressing member includes:

a piston disposed in a hole formed in the attachment surface of the polishing table to which the polishing pad is attached; and

a driving member capable of driving the piston in a direction in which the rear surface of the polishing pad is pressed in the detachment process.

8. A method for attaching a polishing pad, comprising the steps of:

providing a silicone layer on an attachment surface of a polishing table having the attachment surface to which the polishing pad used to polish a substrate is attached;

heat-treating the silicone layer provided on the attachment surface; and

attaching the polishing pad onto the heat-treated silicone layer.

9. A method for replacing a polishing pad including a method for attaching the polishing pad or a method for detaching the polishing pad from a polishing table, the method for attaching the polishing pad comprising the steps of: providing a silicone layer on an attachment surface of the polishing table having the attachment surface to which the polishing pad used to polish a substrate is attached; heat-treating the silicone layer provided on the attachment surface; and attaching the polishing pad onto the heat-treated silicone layer, the method for replacing the polishing pad comprising the step of:

pressurizing a rear surface of the polishing pad attached to the polishing table in a detachment process of detaching the polishing pad from the polishing table, the rear surface being a side of the polishing pad opposite to its polishing surface, or

pressurizing or depressurizing the rear surface of the polishing pad in an attachment process of attaching the polishing pad to the polishing table.

10. The method for replacing a polishing pad according to claim 9, wherein a piston disposed in a hole formed in the attachment surface of the polishing table to which the polishing pad is attached is driven in a direction in which the rear surface of the polishing pad is pressed in the process of detaching the polishing pad.

11. The polishing apparatus according to claim 2, wherein the silicone layer includes resin-based paint prepared by mixing ceramic with silicon and coated on the attachment surface.

12. The polishing apparatus according to claim 11, wherein the polishing table is formed by containing at least one of silicon carbide, stainless steel, resin, and aluminum oxide.

13. The polishing apparatus according to claim 12, further comprising an adhesive agent of the polishing pad interposed between the silicone layer and the polishing pad.

14. The polishing apparatus according to claim 3, wherein the polishing table is formed by containing at least one of silicon carbide, stainless steel, resin, and aluminum oxide.

15. The polishing apparatus according to claim 3, further comprising an adhesive agent of the polishing pad interposed between the silicone layer and the polishing pad.

16. The polishing apparatus according to claim 3, further comprising a control unit configured to pressurize or depressurize a rear surface of the polishing pad attached to the polishing table, the rear surface being a side of the polishing pad opposite to its polishing surface, wherein the control unit pressurizes the rear surface of the polishing pad in a detachment process of detaching the polishing pad from the polishing table, or pressurizes or depressurizes the rear surface of the polishing pad in an attachment process of attaching the polishing pad to the polishing table.

17. The polishing apparatus according to claim 3, further comprising a pressing member configured to press the rear surface of the polishing pad in the detachment process of detaching the polishing pad from the polishing table, wherein the pressing member includes: