U.S. patent application number 14/372446 was filed with the patent office on 2015-04-30 for polishing apparatus, method for attaching polishing pad, and method for replacing polishing pad.
The applicant listed for this patent is EBARA CORPORATION. Invention is credited to Kaoru Hamaura, Eiji Hirai, Soichi Isobe, Ryuichi Kosuge, Suguru Ogura, Takeshi Sakurai, Tadakazu Sone.
Application Number | 20150118944 14/372446 |
Document ID | / |
Family ID | 52113191 |
Filed Date | 2015-04-30 |
United States Patent
Application |
20150118944 |
Kind Code |
A1 |
Kosuge; Ryuichi ; et
al. |
April 30, 2015 |
POLISHING APPARATUS, METHOD FOR ATTACHING POLISHING PAD, AND METHOD
FOR REPLACING POLISHING PAD
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 110a 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
110a 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.
Inventors: |
Kosuge; Ryuichi; (Tokyo,
JP) ; Sone; Tadakazu; (Tokyo, JP) ; Isobe;
Soichi; (Tokyo, JP) ; Sakurai; Takeshi;
(Tokyo, JP) ; Hirai; Eiji; (Tokyo, JP) ;
Hamaura; Kaoru; (Tokyo, JP) ; Ogura; Suguru;
(Tokyo, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
EBARA CORPORATION |
Tokyo |
|
JP |
|
|
Family ID: |
52113191 |
Appl. No.: |
14/372446 |
Filed: |
January 29, 2014 |
PCT Filed: |
January 29, 2014 |
PCT NO: |
PCT/JP2014/051905 |
371 Date: |
July 15, 2014 |
Current U.S.
Class: |
451/287 ;
29/402.08; 29/428; 451/490 |
Current CPC
Class: |
Y10T 29/4973 20150115;
B24B 45/006 20130101; B24B 37/34 20130101; B24B 37/04 20130101;
Y10T 29/49826 20150115 |
Class at
Publication: |
451/287 ;
451/490; 29/428; 29/402.08 |
International
Class: |
B24B 37/34 20060101
B24B037/34; B24B 45/00 20060101 B24B045/00; B24B 37/04 20060101
B24B037/04 |
Foreign Application Data
Date |
Code |
Application Number |
Jan 31, 2013 |
JP |
2013-016876 |
Feb 12, 2013 |
JP |
2013-024425 |
Apr 24, 2013 |
JP |
2013-091617 |
Aug 22, 2013 |
JP |
2013-172189 |
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: 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.
Description
TECHNICAL FIELD
[0001] 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
[0002] 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.
[0003] 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.
[0004] 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.
[0005] 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.
[0006] 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.
[0007] 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.
[0008] 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
[0009] Patent Literature 1: Japanese Patent Laid-Open No.
2008-238375 [0010] Patent Literature 2: Japanese Patent Laid-Open
No. 2007-20339 [0011] Patent Literature 3: Japanese Patent
Laid-Open No. 10-217148
SUMMARY OF INVENTION
Technical Problem
[0012] 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.
[0013] 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.degree. C. to 400.degree. C.
[0014] 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.
[0015] 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.
[0016] 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.
[0017] 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.
[0018] 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.
[0019] 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.
[0020] 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.
[0021] 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.
[0022] 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
[0023] 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.
[0024] 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.
[0025] The silicone layer may also include resin-based paint
prepared by mixing ceramic with silicon and coated on the
attachment surface.
[0026] The polishing table may be formed by containing at least one
of silicon carbide, stainless steel, resin, and aluminum oxide.
[0027] The polishing apparatus may further include an adhesive
agent of the polishing pad interposed between the silicone layer
and the polishing pad.
[0028] 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.
[0029] 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.
[0030] 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.
[0031] 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.
[0032] 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
[0033] 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.
[0034] 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.
[0035] 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
[0036] FIG. 1 is a drawing schematically illustrating the overall
configuration of a polishing apparatus of a first embodiment.
[0037] FIG. 2 is a drawing illustrating a mode of adhesion between
a polishing pad and a polishing table.
[0038] FIG. 3 is a drawing illustrating a flow of the process of
attaching a polishing pad and a polishing process.
[0039] FIG. 4 is a drawing schematically illustrating the overall
configuration of a polishing apparatus of a second embodiment.
[0040] FIG. 5 is a drawing schematically illustrating the detailed
peripheral configuration of a polishing table.
[0041] FIG. 6 is a drawing illustrating, by way of example, array
patterns of a plurality of holes formed in a polishing table.
[0042] FIG. 7 is a drawing illustrating a flow of the process of
detaching a polishing pad.
[0043] FIG. 8 is a drawing schematically illustrating the way the
process of detaching the polishing pad is carried out.
[0044] FIG. 9 is a drawing illustrating a flow of the process of
attaching a polishing pad.
[0045] FIG. 10 is a drawing schematically illustrating the way the
process of attaching the polishing pad is carried out.
[0046] FIG. 11 is a drawing schematically illustrating the overall
configuration of a polishing apparatus.
[0047] FIG. 12 is a drawing schematically illustrating a polishing
apparatus of a third embodiment.
[0048] FIG. 13 is a drawing illustrating details on a pressing
member.
[0049] FIG. 14 is a drawing illustrating another example of the
pressing member.
[0050] FIG. 15 is a drawing schematically illustrating the way the
process of detaching the polishing pad is carried out.
[0051] FIG. 16 is a drawing schematically illustrating a polishing
apparatus of a fourth embodiment.
[0052] FIG. 17 is a drawing schematically illustrating a polishing
apparatus of a fifth embodiment.
DESCRIPTION OF EMBODIMENTS
First Embodiment
[0053] 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.
[0054] 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.
[0055] 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.
[0056] 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.
[0057] 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 108b on the opposite
side of a polishing surface 108a of the polishing pad 108. In
addition, a silicone layer 111 is provided on an attachment surface
110a 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.
[0058] The silicone layer 111 may include a silicone
resin-containing adhesive agent coated on the attachment surface
110a of the polishing table 110. In this case, the silicone
resin-containing adhesive agent can be coated on the attachment
surface 110a of the polishing table 110 by various methods,
including brush coating, roller coating, blast coating and spray
coating.
[0059] The silicone layer 111 may also include a silicone
resin-containing adhesive sheet bonded to the attachment surface
10a of the polishing table 110.
[0060] 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 110a 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 110a
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.
[0061] 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).
[0062] 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.
[0063] As illustrated in FIG. 3, an attachment process is first
carried out by coating a silicone adhesive agent on a surface
(attachment surface 110a) 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.degree. C. to 200.degree. 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 110a of the polishing table
110.
[0064] 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 108b 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.
[0065] 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.
[0066] Then, the polishing process is carried out by pressing the
substrate 102 held on the top ring 116 against the polishing
surface 108a 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.
[0067] 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).
[0068] 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.
[0069] That is, in the present embodiment, the silicone layer 111
is interposed between the attachment surface 110a 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 110a.
[0070] 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 110a. In
addition, adhesive force in the shear direction of the polishing
pad 108 (direction along the attachment surface 110a) 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.
[0071] 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.
[0072] 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.
[0073] 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.degree. C. to 400.degree. 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.
[0074] 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.degree. C. to 200.degree. 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.degree. C. to 400.degree. C. can
be obtained, even if the silicone layer 111 is heat-treated at such
a relatively low temperature as approximately 150.degree. C. to
200.degree. C.
[0075] 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.
[0076] 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 .mu.m, it is possible to maintain the planarity of
the polishing table 110.
[0077] 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
[0078] 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.
[0079] 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.
[0080] 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.
[0081] 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.
[0082] 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.
[0083] 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.
[0084] 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 1110a to which the polishing pad 1108 is
attached and the surface 1110b on the opposite side of the
attachment surface 1110a is formed in the polishing table 1110. The
holes 1111 are one example of communication passages for
communicating the rear surface 1108b on the opposite side of the
polishing surface 1108a 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 1108b of the polishing pad 1108 with the outer
portions of the polishing table 1110.
[0085] 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.
[0086] The control unit 1140 pressurizes the rear surface 1108b of
the polishing pad 1108 in a detachment process by blowing a fluid
(air) onto the rear surface 1108b of the polishing pad 1108 through
the holes 1111. In addition, the control unit 1140 pressurizes the
rear surface 1108b of the polishing pad 1108 in an attachment
process by blowing a fluid (air) onto the rear surface 1108b of the
polishing pad 1108 through the holes 1111, or depressurizes the
rear surface 1108b of the polishing pad 1108 (rear surface 1108b
side) by sucking the fluid from the rear surface 1108b of the
polishing pad 1108 through the holes 1111. Note that depressurizing
the rear surface 1108b of the polishing pad 1108 means reducing a
pressure applied to the rear surface 1108b.
[0087] 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.
[0088] 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.
[0089] 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.
[0090] 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.
[0091] 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."
[0092] 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.
[0093] 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.
[0094] 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 1111a 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 1108b 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.
[0095] 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.
[0096] 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."
[0097] 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).
[0098] 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 1111b
in FIG. 6(b)) adjacent to a hole 1111 (for example, the first hole
1111a in FIG. 6(b)) into which air is injected first, and injects
air into the hole 1111b.
[0099] 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 1108b of the polishing pad 1108 by air injection.
The operator can therefore easily detach the polishing pad
1108.
[0100] 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.
[0101] 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.
[0102] 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.
[0103] 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).
[0104] 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."
[0105] 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.
[0106] As a result, even if a pocket of trapped air 1107 is
produced between the rear surface 1108b of the polishing pad 1108
and the attachment surface 1110a 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.
[0107] 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."
[0108] 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.
[0109] 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."
[0110] 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 1108b
of the polishing pad 1108, as illustrated in FIG. 10(d).
[0111] 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.
[0112] 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.
[0113] 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."
[0114] 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."
[0115] 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.
[0116] 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.
[0117] 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.
[0118] As described above, according to the present embodiment, the
rear surface 1108b 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 1108b 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 1108b 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
[0119] 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
[0120] 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.
[0121] 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.
[0122] 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.
[0123] The control unit 2140 is a controller used to press a rear
surface 2108b 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.
[0124] 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.
[0125] 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.
[0126] 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
2110a of the polishing table 2110 to which the polishing pad 2108
is attached. Specifically, a hole (communication passage) 2111
communicating the attachment surface 2110a to which the polishing
pad 2108 is attached with a surface (the rear surface 2110b of the
polishing table 2110 in the present embodiment) other than the
attachment surface 2110a is formed in the polishing table 2110.
[0127] A pressing member 2200 for pressing the rear surface 2108b
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.
[0128] 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
2108b 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 2210a for pressing the rear
surface 2108b of the polishing pad 2108 in the detachment
process.
[0129] 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 2110b
of the polishing table 2110 (in a direction in which the piston
2210 moves away from the rear surface 2108b 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.
[0130] 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 2210a of the piston 2210 and the attachment
surface 2110a 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.
[0131] 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
2110b of the polishing table 2110 through the shim member 2250 with
screws 242.
[0132] When the piston 2210 moves in the direction toward the rear
surface 2110b 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 2210a of the piston 2210 and the attachment
surface 2110a 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.
[0133] The driving member 2220 is provided with a cylinder 2260 in
which first and second communicating ports 2260a and 2260b 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 2260a within the cylinder 2260
and a second space 2264 communicated with the second communicating
port 2260b 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.
[0134] 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 2108b of the polishing pad 2108
by means of fluid inflow into or fluid outflow from the first and
second communicating ports 2260a and 2260b. 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 2108b 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.
[0135] 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.
[0136] As illustrated in FIG. 12, the compressed-air lines 2152-1
and 2152-2 are connected to the first and second communicating
ports 2260a and 2260b, 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.
[0137] 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.
[0138] 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 2260a 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.
[0139] 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 2260b 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 2108b of
the polishing pad 2108 to detach the polishing pad 2108.
[0140] 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
[0141] 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.
[0142] 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.
[0143] 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.
[0144] 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.
[0145] 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 2108b of the polishing pad 2108 to detach
the polishing pad 2108.
[0146] 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
[0147] 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.
[0148] 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.
[0149] 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.
[0150] 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.
[0151] 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.
[0152] 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 2108b of
the polishing pad 2108 to detach the polishing pad 2108.
[0153] 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
[0154] 100 Polishing apparatus [0155] 102 Substrate [0156] 108
Polishing pad [0157] 108a Polishing surface [0158] 108b Rear
surface [0159] 109 Adhesive surface [0160] 110 Polishing table
[0161] 110a Attachment surface [0162] 111 Silicone layer [0163]
1100 Polishing apparatus [0164] 1102 Substrate [0165] 1107 Pocket
of trapped air [0166] 1108 Polishing pad [0167] 1108a Polishing
surface [0168] 1108b Rear surface [0169] 1109 Beginning end [0170]
1110 Polishing table [0171] 1110a Attachment surface [0172] 1110b
Surface on the opposite side of attachment surface [0173] 1111 Hole
[0174] 1130 Operating panel [0175] 1140 Control unit [0176] 1152
Compressed-air line [0177] 1154 Vacuum line [0178] 1159 Conduction
path [0179] 1160 Rotary joint [0180] 1170 Rotary connector [0181]
1182 Pressure sensor [0182] 2100 Polishing apparatus [0183] 2102
Substrate [0184] 2108 Polishing pad [0185] 2108b Rear surface
[0186] 2110 Polishing table [0187] 2110a Attachment surface [0188]
2110b Rear surface [0189] 2111 Hole [0190] 2152 Compressed-air line
[0191] 2158-1, 2158-2 Valve [0192] 2200 Pressing member [0193] 2210
Piston [0194] 2210a Abutting surface [0195] 2220 Driving member
[0196] 2240 Stopper member [0197] 2240-a Cylindrical portion [0198]
2240-b Flange portion [0199] 2250 Shim member [0200] 2260 Cylinder
[0201] 2260a First communicating port [0202] 2260b Second
communicating port [0203] 2262 First space [0204] 2264 Second space
[0205] 2270 Partitioning member [0206] 280 Coupling member
* * * * *