US20060128286A1 - Polishing apparatus - Google Patents
Polishing apparatus Download PDFInfo
- Publication number
- US20060128286A1 US20060128286A1 US10/562,877 US56287705A US2006128286A1 US 20060128286 A1 US20060128286 A1 US 20060128286A1 US 56287705 A US56287705 A US 56287705A US 2006128286 A1 US2006128286 A1 US 2006128286A1
- Authority
- US
- United States
- Prior art keywords
- ring
- retainer ring
- polishing
- housing
- top ring
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
- 238000005498 polishing Methods 0.000 title claims abstract description 200
- 230000002093 peripheral effect Effects 0.000 claims abstract description 31
- 238000003825 pressing Methods 0.000 claims abstract description 27
- 239000000919 ceramic Substances 0.000 claims description 14
- 229910052751 metal Inorganic materials 0.000 claims description 11
- 239000002184 metal Substances 0.000 claims description 11
- 239000002245 particle Substances 0.000 claims description 11
- 239000011347 resin Substances 0.000 claims description 11
- 229920005989 resin Polymers 0.000 claims description 11
- 239000004065 semiconductor Substances 0.000 abstract description 76
- 239000012530 fluid Substances 0.000 description 29
- 238000005452 bending Methods 0.000 description 27
- 239000002002 slurry Substances 0.000 description 21
- 239000000463 material Substances 0.000 description 19
- 230000007246 mechanism Effects 0.000 description 13
- 238000009826 distribution Methods 0.000 description 12
- 239000007788 liquid Substances 0.000 description 12
- 239000010410 layer Substances 0.000 description 9
- 238000004891 communication Methods 0.000 description 6
- 229920001971 elastomer Polymers 0.000 description 6
- 238000004140 cleaning Methods 0.000 description 4
- 238000005520 cutting process Methods 0.000 description 4
- 230000000694 effects Effects 0.000 description 4
- 238000000034 method Methods 0.000 description 4
- 238000007517 polishing process Methods 0.000 description 4
- 239000000126 substance Substances 0.000 description 4
- 239000004696 Poly ether ether ketone Substances 0.000 description 3
- 239000004734 Polyphenylene sulfide Substances 0.000 description 3
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 description 3
- 230000007774 longterm Effects 0.000 description 3
- 229920002530 polyetherether ketone Polymers 0.000 description 3
- 229920000069 polyphenylene sulfide Polymers 0.000 description 3
- 230000008569 process Effects 0.000 description 3
- 239000000758 substrate Substances 0.000 description 3
- 239000010409 thin film Substances 0.000 description 3
- 239000010936 titanium Substances 0.000 description 3
- 229910052719 titanium Inorganic materials 0.000 description 3
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 3
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- 229920002943 EPDM rubber Polymers 0.000 description 2
- 229920000181 Ethylene propylene rubber Polymers 0.000 description 2
- 239000000853 adhesive Substances 0.000 description 2
- 230000001070 adhesive effect Effects 0.000 description 2
- 239000006260 foam Substances 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 239000012528 membrane Substances 0.000 description 2
- 239000011295 pitch Substances 0.000 description 2
- 229920002635 polyurethane Polymers 0.000 description 2
- 239000004814 polyurethane Substances 0.000 description 2
- 229920003225 polyurethane elastomer Polymers 0.000 description 2
- 229920002379 silicone rubber Polymers 0.000 description 2
- 239000004945 silicone rubber Substances 0.000 description 2
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 1
- 230000002411 adverse Effects 0.000 description 1
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 1
- 125000003118 aryl group Chemical group 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 230000006866 deterioration Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000002708 enhancing effect Effects 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 239000004744 fabric Substances 0.000 description 1
- 239000010408 film Substances 0.000 description 1
- 238000009413 insulation Methods 0.000 description 1
- 230000003993 interaction Effects 0.000 description 1
- 238000001459 lithography Methods 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 238000005459 micromachining Methods 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 238000000465 moulding Methods 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- 239000004745 nonwoven fabric Substances 0.000 description 1
- 238000000059 patterning Methods 0.000 description 1
- 239000004033 plastic Substances 0.000 description 1
- 229920003023 plastic Polymers 0.000 description 1
- 239000000088 plastic resin Substances 0.000 description 1
- 239000004431 polycarbonate resin Substances 0.000 description 1
- 229920005668 polycarbonate resin Polymers 0.000 description 1
- 229920001721 polyimide Polymers 0.000 description 1
- 239000009719 polyimide resin Substances 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 239000002356 single layer Substances 0.000 description 1
- 229920002803 thermoplastic polyurethane Polymers 0.000 description 1
- 238000009827 uniform distribution Methods 0.000 description 1
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B24—GRINDING; POLISHING
- B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
- B24B37/00—Lapping machines or devices; Accessories
- B24B37/27—Work carriers
- B24B37/30—Work carriers for single side lapping of plane surfaces
- B24B37/32—Retaining rings
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B24—GRINDING; POLISHING
- B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
- B24B49/00—Measuring or gauging equipment for controlling the feed movement of the grinding tool or work; Arrangements of indicating or measuring equipment, e.g. for indicating the start of the grinding operation
- B24B49/16—Measuring or gauging equipment for controlling the feed movement of the grinding tool or work; Arrangements of indicating or measuring equipment, e.g. for indicating the start of the grinding operation taking regard of the load
Definitions
- the present invention relates to a polishing apparatus, and more articularly to a polishing apparatus for polishing a workpiece to be polished, such as a semiconductor wafer, by holding the workpiece and pressing the workpiece against a polishing surface.
- the thickness of the film formed at portions having a step becomes small. Further, an open circuit may be caused by disconnection, or a short circuit may be caused by insufficient insulation between interconnection layers. As a result, good products cannot be obtained, and the yield tends to be lowered. Further, even if a semiconductor device initially works normally, reliability of the semiconductor device is lowered after a long-term use. At the time of exposure in a lithography process, if the irradiation surface has irregularities, then a lens unit in an exposure system is locally unfocused. Therefore, if the irregularities on the surface of the semiconductor device are increased, then it becomes problematically difficult to form a fine pattern itself on the semiconductor device.
- CMP chemical mechanical polishing
- This type of polishing apparatus includes a polishing table having a polishing surface formed by a polishing pad and a top ring for holding a semiconductor wafer.
- a polishing table having a polishing surface formed by a polishing pad and a top ring for holding a semiconductor wafer.
- the semiconductor wafer is held and pressed against the polishing table under a predetermined pressure by the top ring.
- the polishing table and the top ring are moved relative to each other to bring the semiconductor wafer into sliding contact with the polishing surface, so that the surface of the semiconductor wafer is polished to a flat mirror finish.
- the polishing pad is so elastic that pressing forces applied to a peripheral edge portion of the semiconductor wafer tend to be non-uniform. Accordingly, the semiconductor wafer may excessively be polished only at the peripheral edge portion to thus cause edge rounding.
- FIG. 1 there has been employed a top ring having a structure for holding a side edge portion of a semiconductor wafer W by a retainer ring 600 and pressing a polishing surface 610 located outside of a peripheral edge portion of the semiconductor wafer W by the retainer ring 600 .
- this type of top ring as shown in FIG.
- the retainer ring 600 is fixed to a peripheral portion of a disk-like housing (flange portion) 620 and pressed against the polishing surface 610 under a pressing force applied by a top ring shaft 630 , which is connected to a central portion of the housing 620 .
- a portion for pressing a workpiece W to be polished tends to have a complicated structure. Since the top ring has a complicated pressing mechanism, a portion at which the retainer ring 600 is attached to the housing 620 is separated from an outer peripheral edge of the workpiece W in a circumferential direction so as to form an overhanging portion in view of structural mechanics. A bending moment M 0 produced by the overhanging deforms the retainer ring 600 as shown in FIG. 1 so that the surface pressure of the retainer ring 600 to the polishing surface 610 becomes non-uniform. If the retainer ring 600 is partially worn according to progress of polishing time, then a polishing profile varies so as to exert an adverse influence on polishing stability.
- the retainer ring 600 for holding a peripheral portion of the workpiece W is required to have a function to uniformly press the polishing surface 610 of the polishing table in addition to a function to hold the workpiece W.
- the present invention has been made in view of the above drawbacks. It is, therefore, a first object of the present invention to provide a polishing apparatus which can prevent or reduce partial wear of a retainer ring during polishing so as to conduct highly accurate polishing.
- a second object of the present invention is to provide a polishing apparatus which can reduce cost for expendables and environment loads, enhance reliability, and shorten a period of time required to conduct dummy polishing after a new retainer ring is attached to a housing.
- a third object of the present invention is to provide a retainer ring which allows dummy polishing, which has been required to be performed on a polishing apparatus, to be performed on a separate dedicated apparatus or machine tool.
- a polishing apparatus having a polishing surface, a top ring for holding a workpiece to be polished, and a top ring shaft for pressing the top ring against the polishing surface.
- the top ring has a retainer ring for holding a peripheral edge portion of the workpiece, a housing substantially in a form of a disk which is connected to the top ring shaft, and a sliding contact joint interconnecting the retainer ring and the housing in a state such that the retainer ring and the housing are brought into sliding contact with each other.
- the sliding contact joint may comprise a free joint, preferably a ball joint, to bring the retainer ring and the housing into sliding contact with each other.
- a polishing apparatus having a polishing surface, a top ring for holding a workpiece to be polished, and a top ring shaft for pressing the top ring against the polishing surface.
- the top ring has a retainer ring for holding a peripheral edge portion of the workpiece, a housing substantially in a form of a disk which is connected to the top ring shaft, and a joint interconnecting the retainer ring and the housing.
- the joint has a sufficient high rigidity in horizontal and vertical directions and a low flexural rigidity.
- the rigidity of the joint is increased in the horizontal and vertical directions, a load can reliably be transmitted from the top ring shaft to the retainer ring. Further, since the flexural rigidity of the joint is lowered, a bending moment due to a load applied to a central portion of the housing can be absorbed by the joint to reduce a bending moment applied to the retainer ring. Accordingly, it is possible to prevent inclination of the retainer ring and reduce partial wear of the lower surface of the retainer ring.
- the joint is disposed outside of a center of a radial width of the retainer ring.
- a load of the top ring shaft is applied to a portion located outside of the center of the radial width of the retainer ring. Accordingly, a bending moment is produced with respect to the center of the width of the retainer ring. This bending moment cancels a bending moment produced by a load applied to the central portion of the housing. Thus, a bending moment applied to the retainer ring 3 can further be reduced. Accordingly, it is possible to reduce partial wear of the lower surface of the retainer ring more effectively.
- the joint may have a cross-section constricted at a vertically central portion thereof.
- a polishing apparatus having a polishing surface, a top ring for holding a workpiece to be polished, and a top ring shaft for pressing the top ring against the polishing surface.
- the top ring has a retainer ring for holding a peripheral edge portion of the workpiece and a housing substantially in a form of a disk which is connected to the top ring shaft. A rigidity of the housing is increased so that an inclination of a lower surface of the retainer ring is reduced with respect to the polishing surface when the top ring is pressed against the polishing surface.
- the housing may be made of a material having high strength and rigidity, such as metal or ceramics, and thickened so as to have a high rigidity.
- a bending moment becomes unlikely to be applied to the retainer ring even if a load is applied to the central portion of the housing by the top ring shaft. Accordingly, it is possible to prevent partial wear of the retainer ring.
- a polishing apparatus for polishing a workpiece to be polished, such as a semiconductor wafer, to a flat mirror finish.
- the polishing apparatus has a polishing surface and a top ring for holding a workpiece to be polished.
- the top ring has a retainer ring for holding a peripheral edge portion of the workpiece.
- the retainer ring has a first ring member made of resin, a second ring member made of metal or ceramic, and a fastening tool for fastening the first ring member and the second ring member in a manner such that the first ring member and the second ring member can be detached as two layers in a vertical direction.
- the retainer ring can be regenerated merely by replacement of a worn first ring member. Accordingly, it is possible to reduce cost for expendables. Furthermore, when the retainer ring is attached to a lower surface of a peripheral portion of the housing by a detachable fastening tool, a clamp stress is received by the second ring member such as metal or ceramics, which has a high rigidity. Thus, the retainer ring is prevented from being deformed. Therefore, it is possible to shorten a period of time, i.e., downtime, required for a dummy polishing process.
- the first ring member is brought into contact with the polishing surface. It is also desirable that the first ring member includes particles serving as abrasive particles when the first ring member is scraped. In this case, particles scraped from the first ring member of the retainer ring serve as abrasive particles.
- abrasive particles are supplied from the retainer ring by supplying, e.g., pure water to the polishing surface.
- the retainer ring further includes an engagement portion to fit the first ring member and the second ring member into each other. With such an arrangement, it is possible to facilitate assembling the retainer ring and further enhance the reliability of fastening the first ring member and the second ring member.
- the retainer ring is preferably configured such that the retainer ring can be regenerated only by replacement of the first ring member. Since the retainer ring can be regenerated merely by replacement of the first ring member, it is possible to reduce cost for expendables and environment loads.
- the fastening tool comprises a bolt.
- a bolt is used as the fastening tool, it is possible to facilitate fastening, assembling, and disassembling the first ring member and the second ring member.
- a retainer ring for holding a peripheral edge portion of a workpiece to be polished, which is held on a substrate holding surface of a top ring.
- the retainer ring has a first ring member made of resin, a second ring member made of metal or ceramic, and a fastening tool for fastening the first ring member and the second ring member in a manner such that the first ring member and the second ring member can be detached as two layers in a vertical direction.
- the first ring member is polished to have flatness.
- the first ring member and the second ring member can be fastened by a detachable fastening tool to form a retainer ring having a two-layer structure in the vertical direction. Then, the first ring member can be polished so as to have flatness. Accordingly, it is not necessary to conduct dummy polishing on the polishing apparatus which has heretofore been required.
- FIG. 1 is a schematic view showing a conventional top ring
- FIG. 2 is a schematic view showing an entire arrangement of a polishing apparatus according to a first embodiment of the present invention
- FIG. 3 is a vertical cross-sectional view of a top ring in the polishing apparatus shown in FIG. 2 on a cutting plane;
- FIG. 4 is a vertical cross-sectional view of the top ring in the polishing apparatus shown in FIG. 2 on another cutting plane;
- FIG. 5 is a plan view showing a sliding contact joint (housing) of the top ring shown in FIG. 3 ;
- FIG. 6 is a vertical cross-sectional view showing a variation of the top ring shown in FIG. 3 ;
- FIG. 7 is a vertical cross-sectional view showing a top ring according to a second embodiment of the present invention.
- FIG. 8 is a schematic view showing the top ring shown in FIG. 7 ;
- FIG. 9 is a vertical cross-sectional view showing a top ring according to a third embodiment of the present invention.
- FIG. 10A is a vertical cross-sectional view showing an attachment portion of a retainer ring of the top ring shown in FIG. 9 ;
- FIG. 10B is a view showing a surface pressure distribution in the retainer ring shown in FIG. 10A ;
- FIG. 11 is a plan view showing an example of an arrangement of bolts in the retainer ring shown in FIG. 9 ;
- FIG. 12 is a plan view showing another example of an arrangement of bolts in the retainer ring shown in FIG. 9 ;
- FIG. 13A is a vertical cross-sectional view showing an attachment portion of a conventional retainer ring
- FIG. 13B is a view showing a surface pressure distribution in the retainer ring shown in FIG. 13A ;
- FIG. 14 is a vertical cross-sectional view showing a top ring according to a fourth embodiment of the present invention.
- FIG. 15 is a cross-sectional view showing a variation of the top ring shown in FIG. 14 ;
- FIG. 16 is a cross-sectional view showing a variation of the top ring shown in FIG. 14 ;
- FIG. 17A is an enlarged cross-sectional view of a main portion of a top ring according to a fifth embodiment of the present invention.
- FIG. 17B is an enlarged cross-sectional view of a main portion of a top ring according to a sixth embodiment of the present invention.
- FIGS. 18A and 18B are enlarged cross-sectional views showing variations of the retainer ring shown in FIG. 14 ;
- FIG. 19 is an enlarged cross-sectional view showing a variation of the retainer ring shown in FIG. 14 ;
- FIG. 20 is a graph showing a surface pressure distribution along a radial direction of a lower surface of the retainer ring shown in FIG. 17B .
- FIGS. 2 through 20 like or corresponding parts are denoted by like or corresponding reference numerals and will not be described below repetitively.
- FIG. 2 is a schematic view showing an entire arrangement of a polishing apparatus according to a first embodiment of the present invention.
- a polishing table 100 having a polishing pad 101 attached to an upper surface thereof is provided below a top ring 1 .
- a polishing liquid supply nozzle 102 is provided above the polishing table 100 .
- a polishing liquid Q is supplied from the polishing liquid supply nozzle 102 to the polishing pad 101 on the polishing table 100 .
- polishing pads are available on the market.
- some of these are SUBA800, IC-1000, and IC-1000/SUBA400 (two-layer cloth) manufactured by Rodel Inc., and Surfin xxx-5 and Surfin 000 manufactured by Fujimi Inc.
- SUBA800, Surfin xxx-5, and Surfin 000 are non-woven fabrics bonded by urethane resin, and IC-1000 is made of hard rigid foam polyurethane (single layer).
- Foam polyurethane is porous and has a large number of fine recesses or holes formed in its surface.
- the top ring 1 is connected to a top ring shaft 11 via a universal joint 10 , and the top ring shaft 11 is coupled to a top ring air cylinder 111 fixed to a top ring head 110 .
- the top ring 1 has a housing 2 (flange portion) substantially in the form of a disk, which is coupled to a lower end of the top ring shaft 11 , and a retainer ring 3 disposed at a peripheral portion of the housing 2 .
- the top ring air cylinder 111 is connected to a pressure adjustment unit 120 via a regulator R 1 .
- the pressure adjustment unit 120 serves to adjust a pressure by supply of a pressurized fluid such as pressurized air from a compressed air source or by evacuation with pump or the like
- the air pressure of the pressurized air to be supplied to the top ring air cylinder 111 is adjusted via the regulator R 1 by the pressure adjustment unit 120 .
- the top ring air cylinder 111 moves the top ring shaft 11 vertically to raise and lower the whole top ring 1 and press the retainer ring 3 attached to the housing 2 against the polishing table 100 under a predetermined pressing force.
- the top ring shaft 11 is coupled to a rotary sleeve 112 by a key (not shown).
- the rotary sleeve 112 has a timing pulley 113 disposed at a peripheral portion thereof
- a top ring motor 114 is fixed to the top ring head 110 .
- the timing pulley 113 is connected to a timing pulley 116 mounted on the top ring motor 114 via a timing belt 115 . Accordingly, when the top ring motor 114 is energized for rotation, the rotary sleeve 112 and the top ring shaft 11 are rotated in unison with each other via the timing pulley 116 , the timing belt 115 , and the timing pulley 113 to thereby rotate the top ring 1 .
- the top ring head 110 is supported on a top ring head shaft 117 rotatably supported on a frame (not shown).
- FIG. 3 is a vertical cross-sectional view of the top ring 1 shown in FIG. 2 on a cutting plane
- FIG. 4 is a vertical cross-sectional view of the top ring 1 shown in FIG. 2 on another cutting plane
- FIG. 5 is a plan view showing the housing 2 of the top ring 1 shown in FIG. 3 .
- the retainer ring 3 has an upper member 3 a substantially in the form of a cylinder and a lower member 3 b substantially in the form of a cylinder.
- the lower member 3 b has a lower portion projecting inward.
- ball joints 4 are provided as free joints to bring the retainer ring 3 and the housing 2 into sliding contact with each other at a plurality of locations in a circumferential direction of the retainer ring 3 on an upper portion of the upper member 3 a of the retainer ring 3 .
- the ball joints 4 are interposed between hemispherical recesses 2 a formed in a lower surface of the housing 2 and hemispherical recesses 3 c formed in an upper surface of the upper member 3 a of the retainer ring 3 .
- connection bolts 5 are provided on an upper portion of the upper member 3 a of the retainer ring 3 at a plurality of locations in the circumferential direction.
- the housing 2 has spring receivers 2 b corresponding to the connection bolts 5 .
- Coil springs 6 are interposed between the connection bolts 5 and the spring receivers 2 b .
- the ball joints 4 , the connection bolts 5 , the spring receivers 2 b , and the coil springs 6 jointly form sliding contact joints to interconnect the retainer ring 3 and the housing 2 in a state such that the retainer ring 3 and the housing 2 are brought into sliding contact with each other.
- the retainer ring 3 and the housing 2 are brought into sliding contact with each other by the ball joints 4 .
- any means can be used as long as it brings the retainer ring 3 and the housing 2 into sliding contact with each other.
- the top ring shaft 11 is disposed above a central portion of the housing 2 , and the housing 2 is coupled to the top ring shaft 11 by the universal joint 10 .
- the universal joint 10 has a spherical bearing mechanism by which the housing 2 and the top ring shaft 11 are tiltable with respect to each other, and a rotation transmitting mechanism for transmitting rotation of the top ring shaft 11 to the housing 2 . These mechanisms transmit a pressing force and a rotating force from the top ring shaft 11 to the housing 2 while allowing the housing 2 and the top ring shaft 11 to be tilted with respect to each other.
- the spherical bearing mechanism includes a hemispherical recess 11 a defined centrally in a lower surface of the top ring shaft 11 , a hemispherical recess 2 c defined centrally in an upper surface of the housing 2 , and a bearing ball 12 made of a highly hard material such as ceramics and interposed between the recesses 11 a and 2 c .
- connection bolts 7 are mounted near the top ring shaft 11 of the housing 2 .
- Coil springs 8 are interposed between the connection bolts 7 and spring receivers 11 b provided in the top ring shaft 11 .
- the rotation transmitting mechanism includes engagement pins 9 fixed to the housing 2 near the top ring shaft 11 and engagement holes 11 c formed in the top ring shaft 11 . Even if the housing 2 is tilted with respect to the top ring shaft 11 , the engagement pins 9 remain in engagement with the engagement holes 11 c while contact points are displaced because the engagement pins 9 are vertically movable through the engagement holes 11 c . Thus, the rotation transmitting mechanism reliably transmits rotational torque of the top ring shaft 11 to the housing 2 .
- the housing 2 and the retainer ring 3 have a space defined therein, which accommodates therein an elastic pad 20 brought into contact with the semiconductor wafer W held by the top ring 1 , an annular holder ring 21 , and a chucking plate 22 substantially in the form of a disk for supporting the elastic pad 20 .
- the elastic pad 20 has a radially outer edge clamped between the holder ring 21 and the chucking plate 22 fixed to a lower end of the holder ring 21 and covers a lower surface of the chucking plate 22 .
- a pressure chamber 30 is defined between the elastic pad 20 and the chucking plate 22 .
- the elastic pad 20 is made of a highly strong and durable rubber material such as ethylene propylene rubber (EPDM), polyurethane rubber, or silicone rubber.
- An opening 22 a is formed at a central portion of the chucking plate 22 .
- a fluid passage 40 comprising tubes and connectors communicate with the opening 22 a , which is connected to the pressure adjustment unit 120 via a regulator R 2 provided on the fluid passage 40 .
- the pressure chamber 30 between the elastic pad 20 and the chucking plate 22 is connected to the pressure adjustment unit 120 via the regulator R 2 provided on the fluid passage 40 .
- a pressurizing sheet 23 comprising an elastic membrane extends between the holder ring 21 and the housing 2 .
- the pressurizing sheet 23 has one end clamped by a pressurizing sheet support 2 d mounted to a lower surface of the housing 2 and another end clamped between an upper end portion 21 a and a stopper portion 21 b of the holder ring 21 .
- the housing 2 , the chucking plate 22 , the holder ring 21 , and the pressurizing sheet 23 jointly define a pressure chamber 31 in the housing 2 .
- a fluid passage 41 comprising tubes and connectors communicates with the pressure chamber 31 , which is connected to the pressure adjustment unit 120 via a regulator R 3 provided on the fluid passage 41 .
- the pressurizing sheet 23 is made of a highly strong and durable rubber material such as ethylene propylene rubber (EPDM), polyurethane rubber, or silicone rubber.
- the pressure chamber 30 between the chucking plate 22 and the elastic pad 20 and the pressure chamber 31 above the chucking plate 22 are respectively supplied with pressurized fluids such as pressurized air, released to an atmospheric pressure, or evacuated, via the fluid passages 40 and 41 connected to the pressure chambers 30 and 31 .
- the regulators R 2 and R 3 provided on the fluid passages 40 and 41 of the pressure chambers 30 and 31 can respectively regulate pressures of the pressurized fluids to be supplied to the respective pressure chambers.
- the chucking plate 22 has inner suction portions 24 and outer suction portions 25 projecting downward outside of the opening 22 a .
- the inner suction portions 24 have communication holes 24 a communicating with a fluid passage 42 , which comprises tubes and connectors.
- the inner suction portions 40 are connected to the pressure adjustment unit 120 via a regulator R 4 provided on the fluid passage 42 .
- the outer suction portions 25 have communication holes 25 a communicating with a fluid passage 43 , which comprises tubes and connectors.
- the outer suction portions 25 are connected to the pressure adjustment unit 120 via a regulator R 5 provided on the fluid passage 43 .
- Negative pressures can be developed at opening ends of the communication holes 24 a and 25 a of the suction portions 24 and 25 by the pressure adjustment unit 120 , thereby attracting a semiconductor wafer W to the suction portions 24 and 25 .
- the suction portions 24 and 25 have elastic sheets, such as thin rubber sheets, attached to their lower ends, to thereby softly attract and hold the semiconductor wafer W.
- a cleaning liquid passage 26 is formed in the upper member 3 a of the retainer ring 3 .
- the cleaning liquid passage 26 communicates with a slight gap between an outer circumferential surface of the elastic pad 20 and the lower member 3 b of the retainer ring 3 .
- a cleaning liquid (pure water) is supplied to the gap through the cleaning liquid passage 26 .
- the entire top ring 1 is moved to a transferring location of the semiconductor wafer. Then, the communication holes 24 a and 25 a of the suction portions 24 and 25 are connected to the pressure adjustment unit 120 via the fluid passages 42 and 43 .
- the semiconductor wafer W is attracted under vacuum to the lower ends of the suction portions 24 and 25 by suction effect of the communication holes 24 a and 25 a . While the semiconductor wafer W is attracted to the suction portions, the entire top ring 1 is moved to a position above the polishing table 100 having the polishing surface (polishing pad 101 ) thereon. The outer circumferential edge of the semiconductor wafer W is held by the retainer ring 3 so that the semiconductor wafer W is not removed from the top ring 1 .
- the attraction of the semiconductor wafer W by the suction portions 24 and 25 is released, and the semiconductor wafer W is held on the lower surface of the top ring 1 .
- the top ring air cylinder 111 connected to the top ring shaft 11 is actuated to press the retainer ring 3 fixed to the lower end of the top ring 1 against the polishing surface on the polishing table 100 under a predetermined pressing force.
- a pressurized fluid having a predetermined pressure is supplied to the pressure chamber 30 to thereby press the semiconductor wafer W against the polishing surface on the polishing table 100 .
- the polishing liquid supply nozzle 102 supplies a polishing liquid Q onto the polishing pad 101 in advance, so that the polishing liquid Q is held on the polishing pad 101 .
- the semiconductor wafer W is polished with the polishing liquid Q being present between the (lower) surface, to be polished, of the semiconductor wafer W and the polishing pad 101 .
- a pressure fluid is supplied to the pressure chamber 31 through the fluid passage 41 to prevent the chucking plate 22 from being lifted by forces from the pressure chamber 31 .
- the pressing force applied by the top ring air cylinder 111 to press the retainer ring 3 against the polishing pad 101 and the pressing force applied by the pressurized air supplied to the pressure chamber 30 to press the semiconductor wafer W against the polishing pad 101 are appropriately adjusted to polish the semiconductor wafer W.
- the semiconductor wafer W is attracted to the lower ends of the suction portions 24 and 25 under vacuum.
- the supply of the pressurized-fluid into the pressure chamber 30 to press the semiconductor wafer W against the polishing surface is stopped, and the pressure chamber 30 is vented to the atmosphere. Accordingly, the lower ends of the suction portions 24 and 25 are brought into contact with the semiconductor wafer W.
- the pressure chamber 31 is vented to the atmosphere or evacuated to develop a negative pressure therein. If the pressure chamber 31 is maintained at a high pressure, then the semiconductor wafer W is strongly pressed against the polishing surface only in areas brought into contact with the suction portions 40 .
- the entire top ring 1 is moved to a transferring position of the semiconductor wafer W, and then a fluid (e.g., compressed air or a mixture of nitrogen and pure water) is ejected to the semiconductor wafer W via the communication holes 24 a and 25 a of the suction portions 24 and 25 to release the semiconductor wafer W from the top ring 1 .
- a fluid e.g., compressed air or a mixture of nitrogen and pure water
- the retainer ring 3 and the housing 2 are brought into sliding contact with each other by the ball joints 4 . Accordingly, even if the top ring shaft 11 applies a load to the central portion of the housing 2 , only a vertical component of the load is transmitted to the retainer ring 3 while no bending moment is applied to the retainer ring 3 because the housing 2 and the retainer ring 3 slide with respect to each other. As a result, the retainer ring 3 is not tilted due to a bending moment. Thus, it is possible to prevent partial wear from being caused on a lower surface of the retainer ring 3 .
- the aforementioned bending moment can also be prevented from being applied to the retainer ring 3 by enhancing a rigidity of the housing 2 .
- the housing 2 may be made of a material having high strength and rigidity, such as metal or ceramics, and thickened so as to have a high rigidity.
- an inclination of the lower surface of the retainer ring 3 with respect to the polishing pad 101 is reduced when the top ring 1 is pressed against the polishing pad 101 .
- the housing 2 has a high rigidity, a bending moment becomes unlikely to be applied to the retainer ring 3 even if a load is applied to the central portion of the housing 2 by the top ring shaft 11 . Accordingly, it is possible to prevent partial wear of the retainer ring 3 .
- the aforementioned sliding contact joints can eliminate bending moments applied to the retainer ring 3 . Accordingly, it is not necessary to enhance the rigidity of the housing 2 to prevent generation of bending moments.
- the housing 2 can be thinned so as to be lightweight, thereby improving easiness of maintenance.
- FIG. 7 is a vertical cross-sectional view showing a top ring according to a second embodiment of the present invention.
- a joint 50 is provided instead of the sliding contact joints in the first embodiment.
- the joint 50 interconnects an upper member 3 a of a retainer ring 3 and a housing 2 and has a sufficient high rigidity in horizontal and vertical directions and a low flexural rigidity.
- the joint 50 in order to have a sufficient high rigidity in horizontal and vertical directions and a low flexural rigidity, has a constricted cross-section such that the width of a vertically central portion thereof is smaller than upper and lower portions thereof.
- the rigidity of the joint 50 is increased in the horizontal and vertical directions, a load can reliably be transmitted from the top ring shaft 11 to the retainer ring 3 . Further, since the flexural rigidity of the joint 50 is lowered, a bending moment due to a load applied to the central portion of the housing 2 can be absorbed by the joint 50 to reduce a bending moment applied to the retainer ring 3 . Accordingly, it is possible to prevent inclination of the retainer ring 3 and reduce partial wear of the lower surface of the retainer ring 3 .
- the housing 2 , the joint 50 , and the upper member 3 a of the retainer ring 3 are formed integrally with each other. However, the present invention is not limited to this example.
- the joint 50 having a low flexural rigidity can reduce a bending moment applied to the retainer ring 3 .
- FIG. 7 when the joint 50 is disposed outside of the center of the radial width of the retainer ring 3 , it is possible to further reduce a bending moment applied to the retainer ring 3 .
- a load of the top ring shaft 11 is applied to a portion located outside of the center of the radial width of the retainer ring 3 as shown in FIG. 8 . Accordingly, a bending moment M 1 is produced with respect to the center of the width of the retainer ring 3 .
- This bending moment M 1 cancels a bending moment M 2 produced by a load applied to the central portion of the housing 2 .
- a bending moment applied to the retainer ring 3 can further be reduced. Accordingly, it is possible to reduce partial wear of the lower surface of the retainer ring 3 more effectively.
- one end of a pressurizing sheet 23 is clamped between the upper member 3 a of the retainer ring 3 and a pressurizing sheet support 3 d provided radially inward of the upper member 3 a but may be fixed to the housing 2 as with the first embodiment.
- FIG. 9 is a vertical cross-sectional view showing a top ring 301 according to a third embodiment of the present invention.
- the top ring 301 has a housing 302 and a retainer ring 303 attached to a lower end of a peripheral edge portion of the housing 302 .
- the housing 302 is made of a material having high strength and rigidity, such as metal or ceramics.
- the housing 302 has a housing body 302 a in the form of a cylindrical receptacle and an annular pressurizing sheet support 302 b fitted inside of a cylindrical portion of the housing body 302 a .
- the retainer ring 303 is fixed to a lower end of the housing body 302 a of the housing 302 by bolts 308 .
- the top ring shaft 311 is disposed above a central portion of the housing body 302 a of the housing 302 , and the housing 302 is coupled to the top ring shaft 311 by the universal joint 310 .
- the universal joint 310 has a spherical bearing mechanism by which the housing 302 and the top ring shaft 311 are tiltable with respect to each other, and a rotation transmitting mechanism for transmitting rotation of the top ring shaft 311 to the housing 302 . These mechanisms transmit a pressing force and a rotating force from the top ring shaft 311 to the housing 302 while allowing the housing 302 and the top ring shaft 311 to be tilted with respect to each other.
- the spherical bearing mechanism includes a hemispherical recess 311 a defined centrally in a lower surface of the top ring shaft 311 , a hemispherical recess 302 c defined centrally in an upper surface of the housing body 302 a , and a bearing ball 312 made of a highly hard material such as ceramics and interposed between the recesses 311 a and 302 c .
- the rotation transmitting mechanism includes drive pins (not shown) fixed to the top ring shaft 311 and driven pins (not shown) fixed to the housing body 302 a .
- the rotation transmitting mechanism reliably transmits rotational torque of the top ring shaft 311 to the housing 302 .
- the housing 302 and the retainer ring 303 attached to the housing 302 have a space defined therein, which accommodates therein an elastic pad 304 brought into contact with a semiconductor wafer W, to be polished, held by the top ring 301 , an annular holder ring 305 , annular elastic pad supports 309 and 313 for supporting the elastic pad 304 , and a chucking plate 306 substantially in the form of a disk for supporting the elastic pad supports 309 and 313 .
- the elastic pad 304 has a radially outer edge clamped between the chucking plate 306 and the elastic pad supports 309 and 313 and covers lower surfaces of the elastic pad supports 309 and 313 .
- a pressurizing sheet 307 comprising an elastic membrane extends between the holder ring 305 and the housing 302 .
- the pressurizing sheet 307 has one end clamped between the housing body 302 a of the housing 302 and the pressurizing sheet support 302 b and another end clamped between an upper end portion of the holder ring 305 and the chucking plate 306 .
- the housing 302 , the chucking plate 306 , the holder ring 305 , and the pressurizing sheet 307 jointly define a pressure chamber 314 in the housing 302 .
- a fluid passage 315 such as a pipe is opened to the pressure chamber 314 .
- the fluid passage 315 is connected to a compressed air source via a selector valve or a regulator, which is not shown.
- Ends of fluid passages 316 and 319 such as pipes are opened to a lower surface of the chucking plate 306 .
- the fluid passages 316 and 319 are connected to the compressed air source via a selector valve or a regulator, which is not shown.
- fluid passages 317 and 318 such as pipes are opened to lower surfaces of the elastic pad supports 309 and 313 .
- the fluid passages 317 and 318 are connected to a vacuum source and the compressed air source via a selector valve or a regulator, which is not shown.
- a semiconductor wafer W is attracted to and held on the lower surfaces of the elastic pad supports 309 and 313 .
- the top ring 301 is rotated, the semiconductor wafer W attracted to and held on the lower surface of the housing 302 is pressed against the polishing surface (the upper surface of the polishing pad) 321 on the rotating polishing table 320 .
- the semiconductor wafer W is polished by relative movement between the semiconductor wafer W and the polishing surface 321 .
- FIG. 10A is a vertical cross-sectional view showing an attachment portion of the retainer ring 303 in the top ring 301
- FIG. 10B is a view showing a surface pressure distribution in the retainer ring 303
- the retainer ring 303 has a first ring member 331 made of resin and a second ring member 332 made of metal or ceramics which has substantially the same plane shape as the first ring member 331 .
- the first ring member 331 is fastened to a lower surface of the second ring member 332 by bolts 333 .
- An annular groove 332 a is formed in the lower surface of the second ring member 332 .
- the first ring member 331 has an annular projection 331 a formed on its upper surface which can fit into the groove 332 a.
- the retainer ring 303 has an engagement portion to engage the first ring member 331 and the second ring member 332 with each other. This arrangement facilitates attachment of the first ring member 331 to the second ring member 332 and strengthens fastening of these members. Such an engagement portion may be eliminated. Instead of the engagement portion, a pin may be used to fix the first ring member 331 and the second ring member 332 to each other.
- Polyetheretherketone (PEEK), polyphenylene sulfide (PPS), full aromatic polyimide resin, which is refractory plastics, or polycarbonate resin can be used as the resin for the first ring member 331 of the retainer ring 303 . It is desirable that the first ring member 331 , which is brought into contact with the polishing surface 321 , contains particles serving as abrasive particles when being scraped or particles that cause no damage to a semiconductor wafer.
- the second ring member 332 is made of metal such as titanium or stainless, or ceramics such as alumina so as to achieve good heat transfer from the first ring member 331 .
- the bolts 333 which fasten the first ring member 331 and the second ring member 332 , may be made of a material having a thermal expansion coefficient close to that of resin of the first ring member 331 or metal (titanium or stainless) or ceramics of the second ring member 332 .
- a material having a high thermal expansion coefficient may preferably be used for the bolts 333 .
- a plurality of bolts 333 may be provided at predetermined pitches along a circumference to fasten the first ring member 331 and the second ring member 332 to each other.
- a plurality of bolts 333 may be provided at predetermined pitches along two circumferences.
- FIG. 13A is a vertical cross-sectional view showing an attachment portion of a retainer ring 440 in a conventional top ring 401 to compare operational effects with the retainer ring 303 having a structure shown in FIG. 10A .
- FIG. 13B is a view showing a surface pressure distribution in the retainer ring 440 .
- the retainer ring 440 is formed integrally of resin and fastened and fixed to a lower surface of a peripheral portion of the housing 302 by bolts.
- top ring 401 including the retainer ring 440 having a structure shown in FIG. 13A is pressed against the polishing surface on the polishing table under a pressing force F, as shown in FIG. 13B , surface pressures P on the lower surface of the retainer ring 440 has a distribution which is substantially uniform from an outer portion to a central portion of the retainer ring 440 but is greatly varied at the inner portion A.
- a ring member made of stainless (or titanium, ceramics) and a ring member made of resin may be bonded to each other by an adhesive to form a two-layer structure.
- Such a retainer ring having a two-layer structure should be discarded due to wear of the ring member made of resin. Accordingly, such a retainer ring suffers high cost for expendables and large environmental loads. Further, aged deterioration of the adhesive or separation due to insufficient adhesion is caused so as to lower the reliability.
- the retainer ring 303 is configured such that the first ring member 331 and the second ring member 332 are fastened to each other by the bolts 333 to form a two-layer structure in the vertical direction. Accordingly, it is possible to achieve high reliability of fastening of the first ring member 331 and the second ring member 332 and regenerate the retainer ring 303 merely by replacement of the worn first ring member 331 .
- the engagement portion is formed by forming the annular groove 332 a in the lower surface of the second ring member 332 and forming the annular projection 331 a , which is fitted into the groove 332 a , in the upper surface of the first ring member 331 .
- the retainer ring 303 is configured such that the first ring member 331 is fastened to the lower surface of the second ring member 332 by the assembly bolts 333 . Accordingly, when the retainer ring 303 is fastened and fixed to the lower surface of the peripheral portion of the housing 302 by the bolts 308 as shown in FIG. 9 , the clamp stress of the bolts 308 is received by the second ring member 332 , which has a rigidity higher than the first ring member 331 . Thus, the retainer ring 303 is prevented from being deformed. Therefore, it is possible to shorten a period of time (downtime) required for a dummy polishing process to eliminate irregularities of the surface of the retainer ring 303 .
- first ring member 331 and the second ring member 332 forming the retainer ring 303 are fastened to each other by the bolts 333 .
- means for fastening the first ring member 331 and the second ring member 332 to each other is not limited to this example.
- Various detachable fastening tools may be employed.
- one of the ring members 331 and 332 may have a step portion having a small outside diameter, and the other of ring members 332 and 331 may have a recess having a large inside diameter.
- Externally threaded grooves may be provided in an outer circumferential surface of the step portion having a small outside diameter while internally threaded grooves may be provided in an inner circumferential surface of the recess having a large inside diameter.
- first ring member 331 and the second ring member 332 may be fastened to each other by screwing the externally threaded grooves and the internally threaded grooves on each other. Further, other mechanical fastening tools may be employed.
- the retainer ring may block polishing slurry to be supplied from the exterior of the retainer ring so as to make it difficult to supply polishing slurry sufficiently to a workpiece to be polished, which is present inside of the retainer ring. Accordingly, slits may be formed in the lower surface of the retainer ring to supply polishing slurry therethrough to a workpiece to be polished, which is present inside of the retainer ring.
- polishing properties vary in a circumferential direction between portions having the slits and portions having no slits. A retainer ring according to the following embodiments can prevent such drawbacks.
- FIG. 14 is a vertical cross-sectional view showing a top ring 510 according to a fourth embodiment of the present invention.
- the top ring 510 holds a semiconductor wafer W as a workpiece to be polished, press the semiconductor wafer W against the polishing surface on the polishing pad 522 , and bring the semiconductor wafer W into sliding contact with the polishing surface to conduct chemical mechanical polishing.
- the top ring 510 has a retainer ring 512 provided on a lower surface of a housing 511 so that a peripheral edge portion of the semiconductor wafer W is held by an inner circumferential surface of the retainer ring 512 .
- a plate 515 is disposed within the housing 511 in a state such that the plate 515 is movable in a vertical direction via an elastic body ring 514 .
- a pressing force to press the semiconductor wafer W against the polishing surface is adjusted by adjusting an air pressure of a pressure chamber 513 , which is surrounded by the plate 515 and the housing 511 . Accordingly, while the semiconductor wafer W is held and pressed by the top ring 510 , it is brought into sliding contact with the polishing surface of the polishing pad 522 fixed on a polishing table 521 . Chemical mechanical polishing is conducted by supplying polishing slurry to the polishing surface.
- a notch 512 a extending radially inward is formed in an outer circumferential surface of the retainer ring 512 .
- the retainer ring 512 is formed of, for example, plastic resin.
- the notch 512 a which has a width of about 0.5 mm to about 1 mm (in a height direction of the retainer ring 512 ), is formed along its perimeter in the present embodiment. It is desirable that the (radial) depth of the notch 512 a is set to be about 2 ⁇ 3 of the (radial) width of the retainer ring 512 .
- the width and depth of the notch 512 a are properly determined according to the size, material, and the like of the entire retainer ring. Further, it is not necessary to form the notch 512 a along its perimeter, and the notch 512 a may partially be formed.
- the rigidity in the vertical direction with respect to the lower surface of the retainer ring 512 can gradually be reduced toward its periphery.
- an area having a low surface pressure is disposed at a peripheral portion of the lower surface of the retainer ring 512 .
- a range in which the top ring has a low pressing force is provided. Accordingly, polishing slurry can readily be introduced into an inner side of the retainer ring 512 . Once the polishing slurry has been introduced into the inner side of the retainer ring 512 , it does not flow out of the retainer ring 512 with ease. Thus, it is possible to increase the amount of polishing slurry supplied to a workpiece held inside of the retainer ring 512 .
- the notch 512 a As shown in FIG. 15 , it is desirable to fill the notch 512 a with an elastic member 519 , such as rubber, by molding or the like.
- an elastic member 519 such as rubber
- polishing slurry is prevented from being introduced into the notch 512 a and being fixed therein.
- the elastic member 519 such as rubber
- the elastic member 519 since the elastic member 519 such as rubber is filled, reduction of the rigidity is not inhibited at the peripheral portion of the top ring.
- the notch 512 a may be formed at a boundary portion of a lower surface of the housing 511 disposed above the retainer ring 512 .
- a non-contact portion (notch) 512 a is provided outside of a joint portion between the retainer ring 512 and the housing 511 . Accordingly, the rigidity of the retainer ring 512 in the vertical direction can be reduced toward an outer side of the retainer ring 512 .
- the surface pressure of the polishing surface on the lower surface of the retainer ring 512 can be reduced toward the outer side of the retainer ring 512 .
- polishing slurry can be prevented from being introduced into an inner side of the retainer ring 512 .
- An elastic member such as rubber may be filled into the non-contact portion 512 a provided between the lower surface of the housing 511 and the upper surface of the retainer ring 512 as shown in FIG. 16 .
- polishing slurry can be prevented from being introduced into and fixed to the interior of the non-contact portion 512 a.
- FIG. 17A shows a portion of a top ring 510 according to a fifth embodiment of the present invention.
- an extended portion 512 c extending outward is disposed at a bottom portion of a cylindrical retainer ring 512 . Because the extended portion 512 c is thinner than a thick portion of the retainer ring 512 , the extended portion 512 c can reduce the vertical rigidity with respect to the lower surface of the retainer ring 512 .
- FIG. 17B shows a portion of a top ring 510 according to a sixth embodiment of the present invention.
- the top ring 510 has a notch 512 a positioned right above an extended portion 512 c .
- the vertical rigidity of the retainer ring 512 can further be reduced toward an outer side of the retainer ring 512 as compared to the structure of the extended portion shown in FIG. 17A .
- the extended portion 512 c shown in FIGS. 17A and 17B preferably has a thickness of about 1 mm to about 2 mm and a radial length of about 5 mm.
- the extended portion 512 c has a width of about 0.5 mm to about 1 mm and a (radial) length that is about 2 ⁇ 3 of a (radial) width of the retainer ring as described above.
- these dimensions should be properly changed according to the overall dimension or material of the retainer ring 512 .
- a material used for a portion of the retainer ring 512 which is brought into contact with the polishing surface may be different from a material used for a portion of the retainer ring 512 which is brought into contact with the housing 511 .
- FIGS. 18A and 18B show examples in which the retainer ring 512 is formed of a plurality of materials.
- a ring member 512 f which is brought into contact with the polishing surface 522 may be made of a corrosion-resistant material
- a retainer portion 512 d which is brought into contact with the housing 511 may be made of stainless.
- an intermediate medium 512 e may be provided on bonding surfaces between the ring member 512 f and the and the retainer portion 512 d .
- the ring member 512 f and the retainer portion 512 d may be bonded directly to each other.
- FIG. 19 shows a variation of the retainer ring 512 shown in FIG. 14 .
- a material used for a portion 512 h that is reduced in rigidity is more likely to be scraped than a material used for a portion 512 g that is not reduced in rigidity.
- the portion 512 h that is reduced in rigidity is made of PPS
- the portion 512 g that is not reduced in rigidity is made of PEEK.
- steps caused by differences of removal rates change a surface pressure distribution of the retainer ring 512 . If an initial surface pressure distribution is changed, the amount of slurry to be supplied to a semiconductor wafer is changed. Accordingly, by using a material that is likely to be scraped for the portion 512 g having a lower rigidity, it is possible to reduce the differences of the amount of removal.
- a scraped portion further reduces the rigidity of a portion that is not scraped. Specifically, by optimizing the positional height and depth of the notch 512 a , a variation of the surface pressure can be reduced even if differences of the amount of removal are produced in the case of the same material.
- a portion having a high rigidity is first scraped so that a high surface pressure is applied to a portion that is not scraped. Accordingly, a uniform distribution of the amount of removal can be achieved by properly designing the size of the notch 512 a.
- FIG. 20 is a graph showing a surface pressure distribution in the retainer ring 512 shown in FIG. 17B .
- the surface pressure distribution is highest on an inner surface R 0 of the retainer ring 512 .
- the surface pressure distribution is lowered on an outer surface R 1 of the retainer ring 512 by interaction of the notch 512 a and the extended portion 512 c .
- the surface pressure is further reduced on an outer surface R 2 of the extended portion 512 c.
- polishing slurry supplied to a central portion of the polishing pad 522 , which is not shown, or a portion of the polishing pad 522 near a peripheral portion of the retainer ring 512 from a nozzle is introduced between the lower surface of the retainer ring 512 and the polishing surface of the polishing pad 522 from the peripheral portion of the retainer ring 512 which has a low surface pressure.
- polishing slurry can readily be supplied to the interior of the retainer ring 512 .
- polishing slurry can be supplied uniformly to the interior of the retainer ring by provision of a portion having a low surface pressure along the perimeter of the retainer ring 512 . Accordingly, polishing slurry can be supplied uniformly to the entire surface of the semiconductor wafer W to be polished. Thus, uniform polishing properties can be obtained.
- polishing slurry When polishing slurry is supplied to an upper surface (polishing surface) of the polishing pad 522 from a rear face of the polishing pad 522 through one or more openings provided in at least portions of the polishing pad 522 which are brought into contact with the semiconductor wafer W, used polishing slurry can satisfactorily be discharged from the surface of the semiconductor wafer W toward the peripheral portion of the retainer ring 512 by effect of the retainer ring 512 having the notch 512 a as described above. Accordingly, since new polishing slurry is continuously supplied uniformly to the entire surface of the surface of the semiconductor wafer W to be polished, uniform polishing properties can be obtained.
- Such a method of supplying polishing slurry is suitable for a revolving polishing pad (having a radius e) or a case in which the top ring 510 passes through a central portion of a rotating polishing pad 522 .
- a slit having a size and a shape such that it does not cancel the aforementioned surface pressure gradient effect of the retainer ring 512 due to the notch 512 a may be provided in a sliding contact surface of the retainer ring so as to promote uniform supply of slurry to the surface to be polished.
- polishing slurry can readily be supplied uniformly to the interior of a retainer ring, which holds a peripheral edge of a workpiece to be polished.
- a polishing apparatus which has good polishing properties over the entire surface of a surface of a workpiece to be polished.
- the present invention can be applied to any top ring which holds a peripheral edge portion of a workpiece and bring the workpiece into sliding contact with a polishing surface.
- the present invention is not limited to examples in which the top ring is rotated while the polishing table is rotated.
- the present invention can be applied to an example in which the top ring holds a workpiece to be polished and make a translational orbital movement with respect to the polishing surface.
- the polishing table is employed in the above embodiments.
- the present invention is not limited to a polishing apparatus having a polishing table.
- the present invention can be applied to any polishing apparatus as long as the polishing apparatus holds a workpiece to be polished by a top ring, presses the workpiece against the polishing surface, and provides a relative movement between the workpiece and the polishing surface to polish the workpiece.
- the present invention is suitably used for a polishing apparatus for polishing a workpiece to be polished, such as a semiconductor wafer, by holding the workpiece and pressing the workpiece against a polishing surface.
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Finish Polishing, Edge Sharpening, And Grinding By Specific Grinding Devices (AREA)
- Mechanical Treatment Of Semiconductor (AREA)
- Grinding-Machine Dressing And Accessory Apparatuses (AREA)
Abstract
A polishing apparatus according to the present invention has a polishing surface (101), a top ring (1) for holding a semiconductor wafer (W), and a top ring shaft (11) for pressing the top ring (1) against the polishing surface (101). The top ring (1) has a retainer ring (3) for holding a peripheral portion of the semiconductor wafer (W), a housing (2) substantially in a form of a disk which is connected to the top ring shaft (11), a sliding contact joint (4, 5, 6, 2 b) interconnecting the retainer ring (3) and the housing (2) in a state such that the retainer ring (3) and the housing (2) are brought into sliding contact with each other.
Description
- The present invention relates to a polishing apparatus, and more articularly to a polishing apparatus for polishing a workpiece to be polished, such as a semiconductor wafer, by holding the workpiece and pressing the workpiece against a polishing surface.
- In recent years, semiconductor devices have become more integrated, and structures of semiconductor elements have become more complicated. Further, the number of layers in multilayer interconnections used for a logical system has been increased. Accordingly, irregularities on a surface of a semiconductor device are increased, so that step heights on the surface of the semiconductor device tend to be large. This is because, in a manufacturing process of a semiconductor device, a thin film is formed on a semiconductor device, then micromachining processes, such as patterning or forming holes, are performed on the semiconductor device, and these processes are repeated to form subsequent thin films on the semiconductor device.
- When the number of irregularities is increased on a surface of a semiconductor device, the following problems arise. When a thin film is formed on a semiconductor device, the thickness of the film formed at portions having a step becomes small. Further, an open circuit may be caused by disconnection, or a short circuit may be caused by insufficient insulation between interconnection layers. As a result, good products cannot be obtained, and the yield tends to be lowered. Further, even if a semiconductor device initially works normally, reliability of the semiconductor device is lowered after a long-term use. At the time of exposure in a lithography process, if the irradiation surface has irregularities, then a lens unit in an exposure system is locally unfocused. Therefore, if the irregularities on the surface of the semiconductor device are increased, then it becomes problematically difficult to form a fine pattern itself on the semiconductor device.
- Thus, in a manufacturing process of a semiconductor device, it increasingly becomes important to planarize a surface of the semiconductor device. One of the most important planarizing technologies is chemical mechanical polishing (CMP). In a chemical mechanical polishing, while a polishing liquid containing abrasive particles such as silica (SiO2) therein is supplied onto a polishing surface such as a polishing pad, a substrate such as a semiconductor wafer is brought into sliding contact with the polishing surface, so that the substrate is polished.
- This type of polishing apparatus includes a polishing table having a polishing surface formed by a polishing pad and a top ring for holding a semiconductor wafer. When a semiconductor wafer is polished with such a polishing apparatus, the semiconductor wafer is held and pressed against the polishing table under a predetermined pressure by the top ring. At that time, the polishing table and the top ring are moved relative to each other to bring the semiconductor wafer into sliding contact with the polishing surface, so that the surface of the semiconductor wafer is polished to a flat mirror finish.
- The polishing pad is so elastic that pressing forces applied to a peripheral edge portion of the semiconductor wafer tend to be non-uniform. Accordingly, the semiconductor wafer may excessively be polished only at the peripheral edge portion to thus cause edge rounding. In order to prevent such edge rounding, as shown in
FIG. 1 , there has been employed a top ring having a structure for holding a side edge portion of a semiconductor wafer W by aretainer ring 600 and pressing apolishing surface 610 located outside of a peripheral edge portion of the semiconductor wafer W by theretainer ring 600. In this type of top ring, as shown inFIG. 1 , theretainer ring 600 is fixed to a peripheral portion of a disk-like housing (flange portion) 620 and pressed against thepolishing surface 610 under a pressing force applied by atop ring shaft 630, which is connected to a central portion of thehousing 620. - In the aforementioned conventional top ring, since the
retainer ring 600 and thehousing 620 are rigidly connected to each other, as shown inFIG. 1 , a bending moment M0 is produced in thehousing 620 and theretainer ring 600 due to a pressing force of thetop ring shaft 630 which is applied to a central portion of thehousing 620. Accordingly, theretainer ring 600 is inclined by deformation due to the bending moment M0. When theretainer ring 600 is thus inclined, the surface pressure is not constant on the lower surface of theretainer ring 600. Therefore, theretainer ring 600 is partially worn. For this reason, highly accurate polishing cannot be achieved. - Specifically, in order to improve a polishing performance, a portion for pressing a workpiece W to be polished tends to have a complicated structure. Since the top ring has a complicated pressing mechanism, a portion at which the
retainer ring 600 is attached to thehousing 620 is separated from an outer peripheral edge of the workpiece W in a circumferential direction so as to form an overhanging portion in view of structural mechanics. A bending moment M0 produced by the overhanging deforms theretainer ring 600 as shown inFIG. 1 so that the surface pressure of theretainer ring 600 to thepolishing surface 610 becomes non-uniform. If theretainer ring 600 is partially worn according to progress of polishing time, then a polishing profile varies so as to exert an adverse influence on polishing stability. - Thus, in the aforementioned polishing apparatus, the
retainer ring 600 for holding a peripheral portion of the workpiece W is required to have a function to uniformly press thepolishing surface 610 of the polishing table in addition to a function to hold the workpiece W. - The present invention has been made in view of the above drawbacks. It is, therefore, a first object of the present invention to provide a polishing apparatus which can prevent or reduce partial wear of a retainer ring during polishing so as to conduct highly accurate polishing.
- A second object of the present invention is to provide a polishing apparatus which can reduce cost for expendables and environment loads, enhance reliability, and shorten a period of time required to conduct dummy polishing after a new retainer ring is attached to a housing.
- A third object of the present invention is to provide a retainer ring which allows dummy polishing, which has been required to be performed on a polishing apparatus, to be performed on a separate dedicated apparatus or machine tool.
- In order to attain the first object, according to a first aspect of the present invention, there is provided a polishing apparatus having a polishing surface, a top ring for holding a workpiece to be polished, and a top ring shaft for pressing the top ring against the polishing surface. The top ring has a retainer ring for holding a peripheral edge portion of the workpiece, a housing substantially in a form of a disk which is connected to the top ring shaft, and a sliding contact joint interconnecting the retainer ring and the housing in a state such that the retainer ring and the housing are brought into sliding contact with each other.
- With such an arrangement, when the top ring is pressed against the polishing surface, the retainer ring and the housing are brought into sliding contact with each other. Accordingly, even if the top ring shaft applies a load to a central portion of the housing, only a vertical component of the load is transmitted to the retainer ring while no bending moment is applied to the retainer ring because the housing and the retainer ring slide with respect to each other. As a result, the retainer ring is not tilted due to a bending moment. Thus, it is possible to prevent partial wear from being caused on a lower surface of the retainer ring.
- The sliding contact joint may comprise a free joint, preferably a ball joint, to bring the retainer ring and the housing into sliding contact with each other.
- According to a second aspect of the present invention, there is provided a polishing apparatus having a polishing surface, a top ring for holding a workpiece to be polished, and a top ring shaft for pressing the top ring against the polishing surface. The top ring has a retainer ring for holding a peripheral edge portion of the workpiece, a housing substantially in a form of a disk which is connected to the top ring shaft, and a joint interconnecting the retainer ring and the housing. The joint has a sufficient high rigidity in horizontal and vertical directions and a low flexural rigidity.
- Thus, since the rigidity of the joint is increased in the horizontal and vertical directions, a load can reliably be transmitted from the top ring shaft to the retainer ring. Further, since the flexural rigidity of the joint is lowered, a bending moment due to a load applied to a central portion of the housing can be absorbed by the joint to reduce a bending moment applied to the retainer ring. Accordingly, it is possible to prevent inclination of the retainer ring and reduce partial wear of the lower surface of the retainer ring.
- It is desirable that the joint is disposed outside of a center of a radial width of the retainer ring. When the joint is disposed outside of the center of the radial width of the retainer ring, a load of the top ring shaft is applied to a portion located outside of the center of the radial width of the retainer ring. Accordingly, a bending moment is produced with respect to the center of the width of the retainer ring. This bending moment cancels a bending moment produced by a load applied to the central portion of the housing. Thus, a bending moment applied to the
retainer ring 3 can further be reduced. Accordingly, it is possible to reduce partial wear of the lower surface of the retainer ring more effectively. The joint may have a cross-section constricted at a vertically central portion thereof. - According to a third aspect of the present invention, there is provided a polishing apparatus having a polishing surface, a top ring for holding a workpiece to be polished, and a top ring shaft for pressing the top ring against the polishing surface. The top ring has a retainer ring for holding a peripheral edge portion of the workpiece and a housing substantially in a form of a disk which is connected to the top ring shaft. A rigidity of the housing is increased so that an inclination of a lower surface of the retainer ring is reduced with respect to the polishing surface when the top ring is pressed against the polishing surface.
- For example, the housing may be made of a material having high strength and rigidity, such as metal or ceramics, and thickened so as to have a high rigidity. Thus, when the housing has a high rigidity, a bending moment becomes unlikely to be applied to the retainer ring even if a load is applied to the central portion of the housing by the top ring shaft. Accordingly, it is possible to prevent partial wear of the retainer ring.
- In order to attain the second object, according to a fourth aspect of the present invention, there is provided a polishing apparatus for polishing a workpiece to be polished, such as a semiconductor wafer, to a flat mirror finish. The polishing apparatus has a polishing surface and a top ring for holding a workpiece to be polished. The top ring has a retainer ring for holding a peripheral edge portion of the workpiece. The retainer ring has a first ring member made of resin, a second ring member made of metal or ceramic, and a fastening tool for fastening the first ring member and the second ring member in a manner such that the first ring member and the second ring member can be detached as two layers in a vertical direction.
- With such an arrangement, it is possible to enhance the reliability of fastening the first ring member and the second ring member. Further, the retainer ring can be regenerated merely by replacement of a worn first ring member. Accordingly, it is possible to reduce cost for expendables. Furthermore, when the retainer ring is attached to a lower surface of a peripheral portion of the housing by a detachable fastening tool, a clamp stress is received by the second ring member such as metal or ceramics, which has a high rigidity. Thus, the retainer ring is prevented from being deformed. Therefore, it is possible to shorten a period of time, i.e., downtime, required for a dummy polishing process.
- It is desirable that the first ring member is brought into contact with the polishing surface. It is also desirable that the first ring member includes particles serving as abrasive particles when the first ring member is scraped. In this case, particles scraped from the first ring member of the retainer ring serve as abrasive particles. Thus, abrasive particles are supplied from the retainer ring by supplying, e.g., pure water to the polishing surface.
- It is desirable that the retainer ring further includes an engagement portion to fit the first ring member and the second ring member into each other. With such an arrangement, it is possible to facilitate assembling the retainer ring and further enhance the reliability of fastening the first ring member and the second ring member.
- The retainer ring is preferably configured such that the retainer ring can be regenerated only by replacement of the first ring member. Since the retainer ring can be regenerated merely by replacement of the first ring member, it is possible to reduce cost for expendables and environment loads.
- It is desirable that the fastening tool comprises a bolt. When a bolt is used as the fastening tool, it is possible to facilitate fastening, assembling, and disassembling the first ring member and the second ring member.
- In order to attain the third object, according to a fifth aspect of the present invention, there is provided a retainer ring for holding a peripheral edge portion of a workpiece to be polished, which is held on a substrate holding surface of a top ring. The retainer ring has a first ring member made of resin, a second ring member made of metal or ceramic, and a fastening tool for fastening the first ring member and the second ring member in a manner such that the first ring member and the second ring member can be detached as two layers in a vertical direction. The first ring member is polished to have flatness.
- Thus, the first ring member and the second ring member can be fastened by a detachable fastening tool to form a retainer ring having a two-layer structure in the vertical direction. Then, the first ring member can be polished so as to have flatness. Accordingly, it is not necessary to conduct dummy polishing on the polishing apparatus which has heretofore been required.
-
FIG. 1 is a schematic view showing a conventional top ring; -
FIG. 2 is a schematic view showing an entire arrangement of a polishing apparatus according to a first embodiment of the present invention; -
FIG. 3 is a vertical cross-sectional view of a top ring in the polishing apparatus shown inFIG. 2 on a cutting plane; -
FIG. 4 is a vertical cross-sectional view of the top ring in the polishing apparatus shown inFIG. 2 on another cutting plane; -
FIG. 5 is a plan view showing a sliding contact joint (housing) of the top ring shown inFIG. 3 ; -
FIG. 6 is a vertical cross-sectional view showing a variation of the top ring shown inFIG. 3 ; -
FIG. 7 is a vertical cross-sectional view showing a top ring according to a second embodiment of the present invention; -
FIG. 8 is a schematic view showing the top ring shown inFIG. 7 ; -
FIG. 9 is a vertical cross-sectional view showing a top ring according to a third embodiment of the present invention; -
FIG. 10A is a vertical cross-sectional view showing an attachment portion of a retainer ring of the top ring shown inFIG. 9 ; -
FIG. 10B is a view showing a surface pressure distribution in the retainer ring shown inFIG. 10A ; -
FIG. 11 is a plan view showing an example of an arrangement of bolts in the retainer ring shown inFIG. 9 ; -
FIG. 12 is a plan view showing another example of an arrangement of bolts in the retainer ring shown inFIG. 9 ; -
FIG. 13A is a vertical cross-sectional view showing an attachment portion of a conventional retainer ring; -
FIG. 13B is a view showing a surface pressure distribution in the retainer ring shown inFIG. 13A ; -
FIG. 14 is a vertical cross-sectional view showing a top ring according to a fourth embodiment of the present invention; -
FIG. 15 is a cross-sectional view showing a variation of the top ring shown inFIG. 14 ; -
FIG. 16 is a cross-sectional view showing a variation of the top ring shown inFIG. 14 ; -
FIG. 17A is an enlarged cross-sectional view of a main portion of a top ring according to a fifth embodiment of the present invention; -
FIG. 17B is an enlarged cross-sectional view of a main portion of a top ring according to a sixth embodiment of the present invention; -
FIGS. 18A and 18B are enlarged cross-sectional views showing variations of the retainer ring shown inFIG. 14 ; -
FIG. 19 is an enlarged cross-sectional view showing a variation of the retainer ring shown inFIG. 14 ; and -
FIG. 20 is a graph showing a surface pressure distribution along a radial direction of a lower surface of the retainer ring shown inFIG. 17B . - Embodiments of a polishing apparatus according to the present invention will be described below with reference to
FIGS. 2 through 20 . InFIGS. 2 through 20 , like or corresponding parts are denoted by like or corresponding reference numerals and will not be described below repetitively. -
FIG. 2 is a schematic view showing an entire arrangement of a polishing apparatus according to a first embodiment of the present invention. As shown inFIG. 2 , a polishing table 100 having apolishing pad 101 attached to an upper surface thereof is provided below atop ring 1. Further, a polishingliquid supply nozzle 102 is provided above the polishing table 100. A polishing liquid Q is supplied from the polishingliquid supply nozzle 102 to thepolishing pad 101 on the polishing table 100. - Various kinds of polishing pads are available on the market. For example, some of these are SUBA800, IC-1000, and IC-1000/SUBA400 (two-layer cloth) manufactured by Rodel Inc., and Surfin xxx-5 and Surfin 000 manufactured by Fujimi Inc. SUBA800, Surfin xxx-5, and Surfin 000 are non-woven fabrics bonded by urethane resin, and IC-1000 is made of hard rigid foam polyurethane (single layer). Foam polyurethane is porous and has a large number of fine recesses or holes formed in its surface.
- The
top ring 1 is connected to atop ring shaft 11 via auniversal joint 10, and thetop ring shaft 11 is coupled to a topring air cylinder 111 fixed to atop ring head 110. Thetop ring 1 has a housing 2 (flange portion) substantially in the form of a disk, which is coupled to a lower end of thetop ring shaft 11, and aretainer ring 3 disposed at a peripheral portion of thehousing 2. - The top
ring air cylinder 111 is connected to apressure adjustment unit 120 via a regulator R1. Thepressure adjustment unit 120 serves to adjust a pressure by supply of a pressurized fluid such as pressurized air from a compressed air source or by evacuation with pump or the like The air pressure of the pressurized air to be supplied to the topring air cylinder 111 is adjusted via the regulator R1 by thepressure adjustment unit 120. The topring air cylinder 111 moves thetop ring shaft 11 vertically to raise and lower the wholetop ring 1 and press theretainer ring 3 attached to thehousing 2 against the polishing table 100 under a predetermined pressing force. - The
top ring shaft 11 is coupled to arotary sleeve 112 by a key (not shown). Therotary sleeve 112 has a timingpulley 113 disposed at a peripheral portion thereof Atop ring motor 114 is fixed to thetop ring head 110. The timingpulley 113 is connected to a timingpulley 116 mounted on thetop ring motor 114 via atiming belt 115. Accordingly, when thetop ring motor 114 is energized for rotation, therotary sleeve 112 and thetop ring shaft 11 are rotated in unison with each other via the timingpulley 116, thetiming belt 115, and the timingpulley 113 to thereby rotate thetop ring 1. Thetop ring head 110 is supported on a topring head shaft 117 rotatably supported on a frame (not shown). - The
top ring 1 will be described in greater details.FIG. 3 is a vertical cross-sectional view of thetop ring 1 shown inFIG. 2 on a cutting plane,FIG. 4 is a vertical cross-sectional view of thetop ring 1 shown inFIG. 2 on another cutting plane, andFIG. 5 is a plan view showing thehousing 2 of thetop ring 1 shown inFIG. 3 . - As shown in
FIGS. 3 and 4 , theretainer ring 3 has anupper member 3 a substantially in the form of a cylinder and alower member 3 b substantially in the form of a cylinder. Thelower member 3 b has a lower portion projecting inward. As shown inFIGS. 3 and 5 ,ball joints 4 are provided as free joints to bring theretainer ring 3 and thehousing 2 into sliding contact with each other at a plurality of locations in a circumferential direction of theretainer ring 3 on an upper portion of theupper member 3 a of theretainer ring 3. The ball joints 4 are interposed betweenhemispherical recesses 2 a formed in a lower surface of thehousing 2 andhemispherical recesses 3 c formed in an upper surface of theupper member 3 a of theretainer ring 3. - As shown in
FIGS. 4 and 5 ,connection bolts 5 are provided on an upper portion of theupper member 3 a of theretainer ring 3 at a plurality of locations in the circumferential direction. Thehousing 2 hasspring receivers 2 b corresponding to theconnection bolts 5. Coil springs 6 are interposed between theconnection bolts 5 and thespring receivers 2 b. Thus, the ball joints 4, theconnection bolts 5, thespring receivers 2 b, and the coil springs 6 jointly form sliding contact joints to interconnect theretainer ring 3 and thehousing 2 in a state such that theretainer ring 3 and thehousing 2 are brought into sliding contact with each other. In the present embodiment, theretainer ring 3 and thehousing 2 are brought into sliding contact with each other by the ball joints 4. However, any means can be used as long as it brings theretainer ring 3 and thehousing 2 into sliding contact with each other. - As described above, the
top ring shaft 11 is disposed above a central portion of thehousing 2, and thehousing 2 is coupled to thetop ring shaft 11 by theuniversal joint 10. Theuniversal joint 10 has a spherical bearing mechanism by which thehousing 2 and thetop ring shaft 11 are tiltable with respect to each other, and a rotation transmitting mechanism for transmitting rotation of thetop ring shaft 11 to thehousing 2. These mechanisms transmit a pressing force and a rotating force from thetop ring shaft 11 to thehousing 2 while allowing thehousing 2 and thetop ring shaft 11 to be tilted with respect to each other. - The spherical bearing mechanism includes a
hemispherical recess 11 a defined centrally in a lower surface of thetop ring shaft 11, ahemispherical recess 2 c defined centrally in an upper surface of thehousing 2, and a bearingball 12 made of a highly hard material such as ceramics and interposed between therecesses FIG. 3 ,connection bolts 7 are mounted near thetop ring shaft 11 of thehousing 2.Coil springs 8 are interposed between theconnection bolts 7 andspring receivers 11 b provided in thetop ring shaft 11. With such a structure, thehousing 2 is held so as to be tiltable with respect to thetop ring shaft 11. - Meanwhile, the rotation transmitting mechanism includes engagement pins 9 fixed to the
housing 2 near thetop ring shaft 11 and engagement holes 11 c formed in thetop ring shaft 11. Even if thehousing 2 is tilted with respect to thetop ring shaft 11, the engagement pins 9 remain in engagement with the engagement holes 11 c while contact points are displaced because the engagement pins 9 are vertically movable through the engagement holes 11 c. Thus, the rotation transmitting mechanism reliably transmits rotational torque of thetop ring shaft 11 to thehousing 2. - The
housing 2 and theretainer ring 3 have a space defined therein, which accommodates therein anelastic pad 20 brought into contact with the semiconductor wafer W held by thetop ring 1, anannular holder ring 21, and a chuckingplate 22 substantially in the form of a disk for supporting theelastic pad 20. Theelastic pad 20 has a radially outer edge clamped between theholder ring 21 and the chuckingplate 22 fixed to a lower end of theholder ring 21 and covers a lower surface of the chuckingplate 22. Thus, apressure chamber 30 is defined between theelastic pad 20 and the chuckingplate 22. Theelastic pad 20 is made of a highly strong and durable rubber material such as ethylene propylene rubber (EPDM), polyurethane rubber, or silicone rubber. - An
opening 22 a is formed at a central portion of the chuckingplate 22. Afluid passage 40 comprising tubes and connectors communicate with the opening 22 a, which is connected to thepressure adjustment unit 120 via a regulator R2 provided on thefluid passage 40. Specifically, thepressure chamber 30 between theelastic pad 20 and the chuckingplate 22 is connected to thepressure adjustment unit 120 via the regulator R2 provided on thefluid passage 40. - A pressurizing
sheet 23 comprising an elastic membrane extends between theholder ring 21 and thehousing 2. The pressurizingsheet 23 has one end clamped by a pressurizingsheet support 2d mounted to a lower surface of thehousing 2 and another end clamped between anupper end portion 21 a and astopper portion 21 b of theholder ring 21. Thehousing 2, the chuckingplate 22, theholder ring 21, and the pressurizingsheet 23 jointly define apressure chamber 31 in thehousing 2. As shown inFIG. 3 , afluid passage 41 comprising tubes and connectors communicates with thepressure chamber 31, which is connected to thepressure adjustment unit 120 via a regulator R3 provided on thefluid passage 41. The pressurizingsheet 23 is made of a highly strong and durable rubber material such as ethylene propylene rubber (EPDM), polyurethane rubber, or silicone rubber. - The
pressure chamber 30 between the chuckingplate 22 and theelastic pad 20 and thepressure chamber 31 above the chuckingplate 22 are respectively supplied with pressurized fluids such as pressurized air, released to an atmospheric pressure, or evacuated, via thefluid passages pressure chambers FIG. 2 , the regulators R2 and R3 provided on thefluid passages pressure chambers pressure chambers pressure chambers - Further, the chucking
plate 22 hasinner suction portions 24 andouter suction portions 25 projecting downward outside of the opening 22 a. Theinner suction portions 24 havecommunication holes 24 a communicating with afluid passage 42, which comprises tubes and connectors. Theinner suction portions 40 are connected to thepressure adjustment unit 120 via a regulator R4 provided on thefluid passage 42. Similarly, theouter suction portions 25 havecommunication holes 25 a communicating with afluid passage 43, which comprises tubes and connectors. Theouter suction portions 25 are connected to thepressure adjustment unit 120 via a regulator R5 provided on thefluid passage 43. Negative pressures can be developed at opening ends of the communication holes 24 a and 25 a of thesuction portions pressure adjustment unit 120, thereby attracting a semiconductor wafer W to thesuction portions suction portions - As shown in
FIG. 3 , a cleaningliquid passage 26 is formed in theupper member 3 a of theretainer ring 3. The cleaningliquid passage 26 communicates with a slight gap between an outer circumferential surface of theelastic pad 20 and thelower member 3 b of theretainer ring 3. A cleaning liquid (pure water) is supplied to the gap through the cleaningliquid passage 26. - In the polishing apparatus thus constructed, when a semiconductor wafer W to be delivered, the entire
top ring 1 is moved to a transferring location of the semiconductor wafer. Then, the communication holes 24 a and 25 a of thesuction portions pressure adjustment unit 120 via thefluid passages suction portions top ring 1 is moved to a position above the polishing table 100 having the polishing surface (polishing pad 101) thereon. The outer circumferential edge of the semiconductor wafer W is held by theretainer ring 3 so that the semiconductor wafer W is not removed from thetop ring 1. - For polishing, the attraction of the semiconductor wafer W by the
suction portions top ring 1. Simultaneously, the topring air cylinder 111 connected to thetop ring shaft 11 is actuated to press theretainer ring 3 fixed to the lower end of thetop ring 1 against the polishing surface on the polishing table 100 under a predetermined pressing force. In such a state, a pressurized fluid having a predetermined pressure is supplied to thepressure chamber 30 to thereby press the semiconductor wafer W against the polishing surface on the polishing table 100. The polishingliquid supply nozzle 102 supplies a polishing liquid Q onto thepolishing pad 101 in advance, so that the polishing liquid Q is held on thepolishing pad 101. Thus, the semiconductor wafer W is polished with the polishing liquid Q being present between the (lower) surface, to be polished, of the semiconductor wafer W and thepolishing pad 101. - When a pressurized fluid is supplied to the
pressure chamber 30, an upward force is applied to the chuckingplate 22. Accordingly, in the present embodiment, a pressure fluid is supplied to thepressure chamber 31 through thefluid passage 41 to prevent thechucking plate 22 from being lifted by forces from thepressure chamber 31. - As described above, the pressing force applied by the top
ring air cylinder 111 to press theretainer ring 3 against thepolishing pad 101 and the pressing force applied by the pressurized air supplied to thepressure chamber 30 to press the semiconductor wafer W against thepolishing pad 101 are appropriately adjusted to polish the semiconductor wafer W. When the polishing of the semiconductor wafer W is finished, the semiconductor wafer W is attracted to the lower ends of thesuction portions pressure chamber 30 to press the semiconductor wafer W against the polishing surface is stopped, and thepressure chamber 30 is vented to the atmosphere. Accordingly, the lower ends of thesuction portions pressure chamber 31 is vented to the atmosphere or evacuated to develop a negative pressure therein. If thepressure chamber 31 is maintained at a high pressure, then the semiconductor wafer W is strongly pressed against the polishing surface only in areas brought into contact with thesuction portions 40. - After attraction of the semiconductor wafer W, the entire
top ring 1 is moved to a transferring position of the semiconductor wafer W, and then a fluid (e.g., compressed air or a mixture of nitrogen and pure water) is ejected to the semiconductor wafer W via the communication holes 24 a and 25 a of thesuction portions top ring 1. - As described above, in the present embodiment, when the
top ring 1 is pressed against the polishing surface, theretainer ring 3 and thehousing 2 are brought into sliding contact with each other by the ball joints 4. Accordingly, even if thetop ring shaft 11 applies a load to the central portion of thehousing 2, only a vertical component of the load is transmitted to theretainer ring 3 while no bending moment is applied to theretainer ring 3 because thehousing 2 and theretainer ring 3 slide with respect to each other. As a result, theretainer ring 3 is not tilted due to a bending moment. Thus, it is possible to prevent partial wear from being caused on a lower surface of theretainer ring 3. - Here, the aforementioned bending moment can also be prevented from being applied to the
retainer ring 3 by enhancing a rigidity of thehousing 2. For example, thehousing 2 may be made of a material having high strength and rigidity, such as metal or ceramics, and thickened so as to have a high rigidity. Thus, an inclination of the lower surface of theretainer ring 3 with respect to thepolishing pad 101 is reduced when thetop ring 1 is pressed against thepolishing pad 101. When thehousing 2 has a high rigidity, a bending moment becomes unlikely to be applied to theretainer ring 3 even if a load is applied to the central portion of thehousing 2 by thetop ring shaft 11. Accordingly, it is possible to prevent partial wear of theretainer ring 3. - In the present embodiment, the aforementioned sliding contact joints can eliminate bending moments applied to the
retainer ring 3. Accordingly, it is not necessary to enhance the rigidity of thehousing 2 to prevent generation of bending moments. Thus, as shown inFIG. 6 , thehousing 2 can be thinned so as to be lightweight, thereby improving easiness of maintenance. -
FIG. 7 is a vertical cross-sectional view showing a top ring according to a second embodiment of the present invention. As shown inFIG. 7 , in the present embodiment, a joint 50 is provided instead of the sliding contact joints in the first embodiment. The joint 50 interconnects anupper member 3 a of aretainer ring 3 and ahousing 2 and has a sufficient high rigidity in horizontal and vertical directions and a low flexural rigidity. In the present embodiment, in order to have a sufficient high rigidity in horizontal and vertical directions and a low flexural rigidity, the joint 50 has a constricted cross-section such that the width of a vertically central portion thereof is smaller than upper and lower portions thereof. Even with a constricted cross-section, since the joint 50 receives a load in one direction with its perimeter, a sufficient rigidity can be maintained in the horizontal direction. At that time, bending moments are received by the respective cross-sections. As a result, the flexural rigidity becomes lower than the rigidity in the horizontal direction. - In the present embodiment, since the rigidity of the joint 50 is increased in the horizontal and vertical directions, a load can reliably be transmitted from the
top ring shaft 11 to theretainer ring 3. Further, since the flexural rigidity of the joint 50 is lowered, a bending moment due to a load applied to the central portion of thehousing 2 can be absorbed by the joint 50 to reduce a bending moment applied to theretainer ring 3. Accordingly, it is possible to prevent inclination of theretainer ring 3 and reduce partial wear of the lower surface of theretainer ring 3. In the present embodiment, thehousing 2, the joint 50, and theupper member 3 a of theretainer ring 3 are formed integrally with each other. However, the present invention is not limited to this example. - As described above, the joint 50 having a low flexural rigidity can reduce a bending moment applied to the
retainer ring 3. As shown inFIG. 7 , when the joint 50 is disposed outside of the center of the radial width of theretainer ring 3, it is possible to further reduce a bending moment applied to theretainer ring 3. Specifically, when the joint 50 is disposed outside of the center of the radial width of theretainer ring 3, a load of thetop ring shaft 11 is applied to a portion located outside of the center of the radial width of theretainer ring 3 as shown inFIG. 8 . Accordingly, a bending moment M1 is produced with respect to the center of the width of theretainer ring 3. This bending moment M1 cancels a bending moment M2 produced by a load applied to the central portion of thehousing 2. Thus, a bending moment applied to theretainer ring 3 can further be reduced. Accordingly, it is possible to reduce partial wear of the lower surface of theretainer ring 3 more effectively. - In the present embodiment, one end of a pressurizing
sheet 23 is clamped between theupper member 3 a of theretainer ring 3 and a pressurizingsheet support 3 d provided radially inward of theupper member 3 a but may be fixed to thehousing 2 as with the first embodiment. -
FIG. 9 is a vertical cross-sectional view showing atop ring 301 according to a third embodiment of the present invention. As shown inFIG. 9 , thetop ring 301 has ahousing 302 and aretainer ring 303 attached to a lower end of a peripheral edge portion of thehousing 302. Thehousing 302 is made of a material having high strength and rigidity, such as metal or ceramics. Thehousing 302 has ahousing body 302 a in the form of a cylindrical receptacle and an annularpressurizing sheet support 302 b fitted inside of a cylindrical portion of thehousing body 302 a. Theretainer ring 303 is fixed to a lower end of thehousing body 302 a of thehousing 302 bybolts 308. - The
top ring shaft 311 is disposed above a central portion of thehousing body 302 a of thehousing 302, and thehousing 302 is coupled to thetop ring shaft 311 by theuniversal joint 310. Theuniversal joint 310 has a spherical bearing mechanism by which thehousing 302 and thetop ring shaft 311 are tiltable with respect to each other, and a rotation transmitting mechanism for transmitting rotation of thetop ring shaft 311 to thehousing 302. These mechanisms transmit a pressing force and a rotating force from thetop ring shaft 311 to thehousing 302 while allowing thehousing 302 and thetop ring shaft 311 to be tilted with respect to each other. - The spherical bearing mechanism includes a hemispherical recess 311a defined centrally in a lower surface of the
top ring shaft 311, a hemispherical recess 302 c defined centrally in an upper surface of thehousing body 302 a, and abearing ball 312 made of a highly hard material such as ceramics and interposed between the recesses 311 a and 302 c. Meanwhile, the rotation transmitting mechanism includes drive pins (not shown) fixed to thetop ring shaft 311 and driven pins (not shown) fixed to thehousing body 302 a. Even if thehousing 302 is tilted with respect to thetop ring shaft 311; the drive pins and the driven pins remain in engagement with each other while contact points are displaced because the drive pin and the driven pin are vertically movable relative to each other. Thus, the rotation transmitting mechanism reliably transmits rotational torque of thetop ring shaft 311 to thehousing 302. - The
housing 302 and theretainer ring 303 attached to thehousing 302 have a space defined therein, which accommodates therein anelastic pad 304 brought into contact with a semiconductor wafer W, to be polished, held by thetop ring 301, anannular holder ring 305, annular elastic pad supports 309 and 313 for supporting theelastic pad 304, and achucking plate 306 substantially in the form of a disk for supporting the elastic pad supports 309 and 313. Theelastic pad 304 has a radially outer edge clamped between the chuckingplate 306 and the elastic pad supports 309 and 313 and covers lower surfaces of the elastic pad supports 309 and 313. - A pressurizing
sheet 307 comprising an elastic membrane extends between theholder ring 305 and thehousing 302. The pressurizingsheet 307 has one end clamped between thehousing body 302 a of thehousing 302 and the pressurizingsheet support 302 b and another end clamped between an upper end portion of theholder ring 305 and thechucking plate 306. Thehousing 302, the chuckingplate 306, theholder ring 305, and the pressurizingsheet 307 jointly define apressure chamber 314 in thehousing 302. - An end of a
fluid passage 315 such as a pipe is opened to thepressure chamber 314. Thefluid passage 315 is connected to a compressed air source via a selector valve or a regulator, which is not shown. Ends offluid passages chucking plate 306. Thefluid passages fluid passages fluid passages - By depressurizing the lower surfaces of the elastic pad supports 309 and 313 via the
fluid passage 318, a semiconductor wafer W is attracted to and held on the lower surfaces of the elastic pad supports 309 and 313. While thetop ring 301 is rotated, the semiconductor wafer W attracted to and held on the lower surface of thehousing 302 is pressed against the polishing surface (the upper surface of the polishing pad) 321 on the rotating polishing table 320. Thus, the semiconductor wafer W is polished by relative movement between the semiconductor wafer W and the polishingsurface 321. At that time, compressed air is supplied to thepressure chamber 314 and between the lower surface of thechucking plate 306 and the semiconductor wafer W via thefluid passages surface 321 on the polishing table 320 are adjusted by adjustment of pressures. -
FIG. 10A is a vertical cross-sectional view showing an attachment portion of theretainer ring 303 in thetop ring 301, andFIG. 10B is a view showing a surface pressure distribution in theretainer ring 303. As shown inFIGS. 10A and 10B , theretainer ring 303 has afirst ring member 331 made of resin and asecond ring member 332 made of metal or ceramics which has substantially the same plane shape as thefirst ring member 331. Thefirst ring member 331 is fastened to a lower surface of thesecond ring member 332 bybolts 333. - An
annular groove 332 a is formed in the lower surface of thesecond ring member 332. Thefirst ring member 331 has anannular projection 331 a formed on its upper surface which can fit into thegroove 332 a. - Specifically, the
retainer ring 303 has an engagement portion to engage thefirst ring member 331 and thesecond ring member 332 with each other. This arrangement facilitates attachment of thefirst ring member 331 to thesecond ring member 332 and strengthens fastening of these members. Such an engagement portion may be eliminated. Instead of the engagement portion, a pin may be used to fix thefirst ring member 331 and thesecond ring member 332 to each other. - Polyetheretherketone (PEEK), polyphenylene sulfide (PPS), full aromatic polyimide resin, which is refractory plastics, or polycarbonate resin can be used as the resin for the
first ring member 331 of theretainer ring 303. It is desirable that thefirst ring member 331, which is brought into contact with the polishingsurface 321, contains particles serving as abrasive particles when being scraped or particles that cause no damage to a semiconductor wafer. Thesecond ring member 332 is made of metal such as titanium or stainless, or ceramics such as alumina so as to achieve good heat transfer from thefirst ring member 331. Preferably, thebolts 333, which fasten thefirst ring member 331 and thesecond ring member 332, may be made of a material having a thermal expansion coefficient close to that of resin of thefirst ring member 331 or metal (titanium or stainless) or ceramics of thesecond ring member 332. - In order to achieve good heat transfer from the
first ring member 331 to thesecond ring member 332, it is desirable to enlarge a contact area at the interface. A material having a high thermal expansion coefficient may preferably be used for thebolts 333. Further, as shown inFIG. 11 , a plurality ofbolts 333 may be provided at predetermined pitches along a circumference to fasten thefirst ring member 331 and thesecond ring member 332 to each other. Alternatively, as shown inFIG. 12 , a plurality ofbolts 333 may be provided at predetermined pitches along two circumferences. - When the
top ring 301 including theretainer ring 303 having a structure shown inFIG. 10A is pressed against the polishingsurface 321 on the polishing table 320 under a pressing force F, as shown inFIG. 10B , surface pressures P on the lower surface of thefirst ring member 331 of theretainer ring 303 has a distribution which is slightly small at an inner portion A of thefirst ring member 331 but is substantially uniform from an outer portion to the inner portion. -
FIG. 13A is a vertical cross-sectional view showing an attachment portion of aretainer ring 440 in a conventionaltop ring 401 to compare operational effects with theretainer ring 303 having a structure shown inFIG. 10A .FIG. 13B is a view showing a surface pressure distribution in theretainer ring 440. In the example shown inFIG. 13A , theretainer ring 440 is formed integrally of resin and fastened and fixed to a lower surface of a peripheral portion of thehousing 302 by bolts. - Since the
retainer ring 440 formed integrally of resin is deformed by fastening forces of the bolts attached to thehousing 302, it is necessary to perform a dummy polishing process to remove irregularities on its surface due to deformation after theretainer ring 440 is newly attached to thehousing 302. Such a dummy polishing process increases a downtime of the apparatus. - Further, when the
top ring 401 including theretainer ring 440 having a structure shown inFIG. 13A is pressed against the polishing surface on the polishing table under a pressing force F, as shown inFIG. 13B , surface pressures P on the lower surface of theretainer ring 440 has a distribution which is substantially uniform from an outer portion to a central portion of theretainer ring 440 but is greatly varied at the inner portion A. - Here, in order to prevent partial wear of the retainer ring, a ring member made of stainless (or titanium, ceramics) and a ring member made of resin may be bonded to each other by an adhesive to form a two-layer structure. Such a retainer ring having a two-layer structure should be discarded due to wear of the ring member made of resin. Accordingly, such a retainer ring suffers high cost for expendables and large environmental loads. Further, aged deterioration of the adhesive or separation due to insufficient adhesion is caused so as to lower the reliability.
- In the present embodiment, as shown in
FIG. 10A , theretainer ring 303 is configured such that thefirst ring member 331 and thesecond ring member 332 are fastened to each other by thebolts 333 to form a two-layer structure in the vertical direction. Accordingly, it is possible to achieve high reliability of fastening of thefirst ring member 331 and thesecond ring member 332 and regenerate theretainer ring 303 merely by replacement of the wornfirst ring member 331. Further, the engagement portion is formed by forming theannular groove 332 a in the lower surface of thesecond ring member 332 and forming theannular projection 331 a, which is fitted into thegroove 332 a, in the upper surface of thefirst ring member 331. Accordingly, it is possible to facilitate assembling theretainer ring 303 and further enhance the reliability of fastening of thefirst ring member 331 and thesecond ring member 332. Further, since theretainer ring 303 can be regenerated merely by the replacement of thefirst ring member 331, it is possible to reduce cost for expendables and environment loads. - Further, the
retainer ring 303 is configured such that thefirst ring member 331 is fastened to the lower surface of thesecond ring member 332 by theassembly bolts 333. Accordingly, when theretainer ring 303 is fastened and fixed to the lower surface of the peripheral portion of thehousing 302 by thebolts 308 as shown inFIG. 9 , the clamp stress of thebolts 308 is received by thesecond ring member 332, which has a rigidity higher than thefirst ring member 331. Thus, theretainer ring 303 is prevented from being deformed. Therefore, it is possible to shorten a period of time (downtime) required for a dummy polishing process to eliminate irregularities of the surface of theretainer ring 303. - In the present embodiment, the
first ring member 331 and thesecond ring member 332 forming theretainer ring 303 are fastened to each other by thebolts 333. However, means for fastening thefirst ring member 331 and thesecond ring member 332 to each other is not limited to this example. Various detachable fastening tools may be employed. For example, one of thering members ring members first ring member 331 and thesecond ring member 332 may be fastened to each other by screwing the externally threaded grooves and the internally threaded grooves on each other. Further, other mechanical fastening tools may be employed. - When the lower surface of the retainer ring is brought into uniform contact with the polishing surface, the retainer ring may block polishing slurry to be supplied from the exterior of the retainer ring so as to make it difficult to supply polishing slurry sufficiently to a workpiece to be polished, which is present inside of the retainer ring. Accordingly, slits may be formed in the lower surface of the retainer ring to supply polishing slurry therethrough to a workpiece to be polished, which is present inside of the retainer ring. However, when slits are formed in a sliding contact surface of the retainer ring, polishing properties vary in a circumferential direction between portions having the slits and portions having no slits. A retainer ring according to the following embodiments can prevent such drawbacks.
-
FIG. 14 is a vertical cross-sectional view showing atop ring 510 according to a fourth embodiment of the present invention. Thetop ring 510 holds a semiconductor wafer W as a workpiece to be polished, press the semiconductor wafer W against the polishing surface on thepolishing pad 522, and bring the semiconductor wafer W into sliding contact with the polishing surface to conduct chemical mechanical polishing. Specifically, thetop ring 510 has aretainer ring 512 provided on a lower surface of ahousing 511 so that a peripheral edge portion of the semiconductor wafer W is held by an inner circumferential surface of theretainer ring 512. Further, aplate 515 is disposed within thehousing 511 in a state such that theplate 515 is movable in a vertical direction via anelastic body ring 514. A pressing force to press the semiconductor wafer W against the polishing surface is adjusted by adjusting an air pressure of apressure chamber 513, which is surrounded by theplate 515 and thehousing 511. Accordingly, while the semiconductor wafer W is held and pressed by thetop ring 510, it is brought into sliding contact with the polishing surface of thepolishing pad 522 fixed on a polishing table 521. Chemical mechanical polishing is conducted by supplying polishing slurry to the polishing surface. - As shown in
FIG. 14 , anotch 512 a extending radially inward is formed in an outer circumferential surface of theretainer ring 512. Theretainer ring 512 is formed of, for example, plastic resin. Thenotch 512 a, which has a width of about 0.5 mm to about 1 mm (in a height direction of the retainer ring 512), is formed along its perimeter in the present embodiment. It is desirable that the (radial) depth of thenotch 512 a is set to be about ⅔ of the (radial) width of theretainer ring 512. As a matter of course, the width and depth of thenotch 512 a are properly determined according to the size, material, and the like of the entire retainer ring. Further, it is not necessary to form thenotch 512 a along its perimeter, and thenotch 512 a may partially be formed. - With the
notch 512 a extending radially inward on the outer circumferential surface of theretainer ring 512, the rigidity in the vertical direction with respect to the lower surface of theretainer ring 512 can gradually be reduced toward its periphery. Thus, an area having a low surface pressure is disposed at a peripheral portion of the lower surface of theretainer ring 512. Specifically, a range in which the top ring has a low pressing force is provided. Accordingly, polishing slurry can readily be introduced into an inner side of theretainer ring 512. Once the polishing slurry has been introduced into the inner side of theretainer ring 512, it does not flow out of theretainer ring 512 with ease. Thus, it is possible to increase the amount of polishing slurry supplied to a workpiece held inside of theretainer ring 512. - As shown in
FIG. 15 , it is desirable to fill thenotch 512 a with anelastic member 519, such as rubber, by molding or the like. When thenotch 512 a is filled with theelastic member 519, polishing slurry is prevented from being introduced into thenotch 512 a and being fixed therein. Thus, it is possible to prevent troubles due to long-term use of the top ring. Further, since theelastic member 519 such as rubber is filled, reduction of the rigidity is not inhibited at the peripheral portion of the top ring. - Further, as shown in
FIG. 16 , thenotch 512 a may be formed at a boundary portion of a lower surface of thehousing 511 disposed above theretainer ring 512. Specifically, a non-contact portion (notch) 512 a is provided outside of a joint portion between theretainer ring 512 and thehousing 511. Accordingly, the rigidity of theretainer ring 512 in the vertical direction can be reduced toward an outer side of theretainer ring 512. Thus, the surface pressure of the polishing surface on the lower surface of theretainer ring 512 can be reduced toward the outer side of theretainer ring 512. As a result, as in the above case, polishing slurry can be prevented from being introduced into an inner side of theretainer ring 512. - An elastic member such as rubber may be filled into the
non-contact portion 512 a provided between the lower surface of thehousing 511 and the upper surface of theretainer ring 512 as shown inFIG. 16 . In this case, as with theelastic member 519 shown inFIG. 15 , polishing slurry can be prevented from being introduced into and fixed to the interior of thenon-contact portion 512 a. -
FIG. 17A shows a portion of atop ring 510 according to a fifth embodiment of the present invention. In thistop ring 510, anextended portion 512 c extending outward is disposed at a bottom portion of acylindrical retainer ring 512. Because theextended portion 512 c is thinner than a thick portion of theretainer ring 512, theextended portion 512 c can reduce the vertical rigidity with respect to the lower surface of theretainer ring 512. -
FIG. 17B shows a portion of atop ring 510 according to a sixth embodiment of the present invention. Thetop ring 510 has anotch 512 a positioned right above anextended portion 512 c. With this arrangement, the vertical rigidity of theretainer ring 512 can further be reduced toward an outer side of theretainer ring 512 as compared to the structure of the extended portion shown inFIG. 17A . - For example, the
extended portion 512 c shown inFIGS. 17A and 17B preferably has a thickness of about 1 mm to about 2 mm and a radial length of about 5 mm. When thenotch 512 a is formed as shown inFIG. 17B , it is desirable that theextended portion 512 c has a width of about 0.5 mm to about 1 mm and a (radial) length that is about ⅔ of a (radial) width of the retainer ring as described above. However, these dimensions should be properly changed according to the overall dimension or material of theretainer ring 512. Further, it is not necessary to form theextended portion 512 c and thenotch 512 a along the perimeter of theretainer ring 512, and theextended portion 512 c and thenotch 512 a may partially be provided. - A material used for a portion of the
retainer ring 512 which is brought into contact with the polishing surface may be different from a material used for a portion of theretainer ring 512 which is brought into contact with thehousing 511.FIGS. 18A and 18B show examples in which theretainer ring 512 is formed of a plurality of materials. For example, as shown in FIGS. 18A and 18B, aring member 512 f which is brought into contact with the polishingsurface 522 may be made of a corrosion-resistant material, whereas aretainer portion 512 d which is brought into contact with thehousing 511 may be made of stainless. In such a case, when a notch is formed in an inner circumferential surface of a contacting portion between thering member 512 f and theretainer portion 512 d, the surface pressure can be reduced at an outer side of theretainer ring 512. - In this case, as shown in
FIG. 18A , an intermediate medium 512 e may be provided on bonding surfaces between thering member 512 f and the and theretainer portion 512 d. Alternatively, as shown inFIG. 18B , thering member 512 f and theretainer portion 512 d may be bonded directly to each other. -
FIG. 19 shows a variation of theretainer ring 512 shown inFIG. 14 . In this example, a material used for aportion 512 h that is reduced in rigidity is more likely to be scraped than a material used for aportion 512 g that is not reduced in rigidity. For example, theportion 512 h that is reduced in rigidity is made of PPS, and theportion 512 g that is not reduced in rigidity is made of PEEK. These portions are bonded to each other. With this arrangement, since theportion 512 h having a lower rigidity produces a reduced pressure, a removal rate of theretainer ring 512 becomes lower than theportion 512 g that is not reduced in rigidity. When theretainer ring 512 is used for a long term, steps caused by differences of removal rates change a surface pressure distribution of theretainer ring 512. If an initial surface pressure distribution is changed, the amount of slurry to be supplied to a semiconductor wafer is changed. Accordingly, by using a material that is likely to be scraped for theportion 512 g having a lower rigidity, it is possible to reduce the differences of the amount of removal. - In the embodiment shown in
FIG. 14 , even if differences of the amount of removal are produced, a scraped portion further reduces the rigidity of a portion that is not scraped. Specifically, by optimizing the positional height and depth of thenotch 512 a, a variation of the surface pressure can be reduced even if differences of the amount of removal are produced in the case of the same material. - In the examples shown in
FIGS. 18A and 18B , a portion having a high rigidity is first scraped so that a high surface pressure is applied to a portion that is not scraped. Accordingly, a uniform distribution of the amount of removal can be achieved by properly designing the size of thenotch 512 a. -
FIG. 20 is a graph showing a surface pressure distribution in theretainer ring 512 shown inFIG. 17B . For example, in theretainer ring 512 shown inFIG. 17B , the surface pressure distribution is highest on an inner surface R0 of theretainer ring 512. The surface pressure distribution is lowered on an outer surface R1 of theretainer ring 512 by interaction of thenotch 512 a and theextended portion 512 c. The surface pressure is further reduced on an outer surface R2 of theextended portion 512 c. - Accordingly, the semiconductor wafer W to be polished and the lower surface of the
retainer ring 512 are brought into sliding contact with the polishingsurface 522 between the rotatingtop ring 510 and the polishingsurface 522 on the rotating and/or revolvingpolishing pad 522. Polishing slurry supplied to a central portion of thepolishing pad 522, which is not shown, or a portion of thepolishing pad 522 near a peripheral portion of theretainer ring 512 from a nozzle is introduced between the lower surface of theretainer ring 512 and the polishing surface of thepolishing pad 522 from the peripheral portion of theretainer ring 512 which has a low surface pressure. Thus, the polishing slurry can readily be supplied to the interior of theretainer ring 512. Specifically, polishing slurry can be supplied uniformly to the interior of the retainer ring by provision of a portion having a low surface pressure along the perimeter of theretainer ring 512. Accordingly, polishing slurry can be supplied uniformly to the entire surface of the semiconductor wafer W to be polished. Thus, uniform polishing properties can be obtained. - When polishing slurry is supplied to an upper surface (polishing surface) of the
polishing pad 522 from a rear face of thepolishing pad 522 through one or more openings provided in at least portions of thepolishing pad 522 which are brought into contact with the semiconductor wafer W, used polishing slurry can satisfactorily be discharged from the surface of the semiconductor wafer W toward the peripheral portion of theretainer ring 512 by effect of theretainer ring 512 having thenotch 512 a as described above. Accordingly, since new polishing slurry is continuously supplied uniformly to the entire surface of the surface of the semiconductor wafer W to be polished, uniform polishing properties can be obtained. Such a method of supplying polishing slurry is suitable for a revolving polishing pad (having a radius e) or a case in which thetop ring 510 passes through a central portion of arotating polishing pad 522. - Further, a slit having a size and a shape such that it does not cancel the aforementioned surface pressure gradient effect of the
retainer ring 512 due to thenotch 512 a may be provided in a sliding contact surface of the retainer ring so as to promote uniform supply of slurry to the surface to be polished. - According to the embodiments, polishing slurry can readily be supplied uniformly to the interior of a retainer ring, which holds a peripheral edge of a workpiece to be polished. Thus, there can be provided a polishing apparatus which has good polishing properties over the entire surface of a surface of a workpiece to be polished.
- In the above embodiments, the present invention can be applied to any top ring which holds a peripheral edge portion of a workpiece and bring the workpiece into sliding contact with a polishing surface. Thus, the present invention is not limited to examples in which the top ring is rotated while the polishing table is rotated. For example, the present invention can be applied to an example in which the top ring holds a workpiece to be polished and make a translational orbital movement with respect to the polishing surface.
- The polishing table is employed in the above embodiments. However, the present invention is not limited to a polishing apparatus having a polishing table. The present invention can be applied to any polishing apparatus as long as the polishing apparatus holds a workpiece to be polished by a top ring, presses the workpiece against the polishing surface, and provides a relative movement between the workpiece and the polishing surface to polish the workpiece.
- Although certain preferred embodiments of the present invention have been described above, it should be understood that the present invention is not limited to the above embodiments. As a matter of course, various changes may be made therein without departing from the scope of the present invention.
- The present invention is suitably used for a polishing apparatus for polishing a workpiece to be polished, such as a semiconductor wafer, by holding the workpiece and pressing the workpiece against a polishing surface.
Claims (14)
1. A polishing apparatus comprising:
a polishing surface;
a top ring for holding a workpiece to be polished; and
a top ring shaft for pressing said top ring against said polishing surface, said top ring including:
a retainer ring for holding a peripheral edge portion of the workpiece,
a housing substantially in a form of a disk, said housing being connected to said top ring shaft, and
a sliding contact joint interconnecting said retainer ring and said housing in a state such that said retainer ring and said housing are brought into sliding contact with each other.
2. The polishing apparatus as recited in claim 1 , wherein said sliding contact joint comprises a free joint to bring said retainer ring and said housing into sliding contact with each other.
3. The polishing apparatus as recited in claim 2 , wherein said free joint comprises a ball joint.
4. A polishing apparatus comprising:
a polishing surface;
a top ring for holding a workpiece to be polished; and
a top ring shaft for pressing said top ring against said polishing surface, said top ring including:
a retainer ring for holding a peripheral edge portion of the workpiece,
a housing substantially in a form of a disk, said housing being connected to said top ring shaft, and
a joint interconnecting said retainer ring and said housing, said joint having a sufficient high rigidity in horizontal and vertical directions and a low flexural rigidity.
5. The polishing apparatus as recited in claim 4 , wherein said joint is disposed outside of a center of a radial width of said retainer ring.
6. The polishing apparatus as recited in claim 4 , wherein said joint has a cross-section constricted at a vertically central portion thereof.
7. A polishing apparatus comprising:
a polishing surface;
a top ring for holding a workpiece to be polished; and
a top ring shaft for pressing said top ring against said polishing surface, said top ring including:
a retainer ring for holding a peripheral edge portion of the workpiece, and
a housing substantially in a form of a disk, said housing being connected to said top ring shaft,
wherein a rigidity of said housing is increased so that an inclination of a lower surface of said retainer ring is reduced with respect to said polishing surface when said top ring is pressed against said polishing surface.
8. A polishing apparatus comprising:
a polishing surface; and
a top ring for holding a workpiece to be polished, said top ring including a retainer ring for holding a peripheral edge portion of the workpiece,
wherein said retainer ring includes:
a first ring member made of resin;
a second ring member made of metal or ceramic; and
a fastening tool for fastening said first ring member and said second ring member in a manner such that said first ring member and said second ring member can be detached as two layers in a vertical direction.
9. The polishing apparatus as recited in claim 8 , wherein said first ring member is brought into contact with said polishing surface.
10. The polishing apparatus as recited in claim 9 , wherein said first ring member includes particles serving as abrasive particles when said first ring member is scraped.
11. The polishing apparatus as recited in claim 8 , wherein said retainer ring further includes an engagement portion to fit said first ring member and said second ring member into each other.
12. The polishing apparatus as recited in claim 8 , wherein said retainer ring is configured such that said retainer ring can be regenerated merely by replacement of said first ring member.
13. The polishing apparatus as recited in claim 8 , where said fastening tool comprises a bolt.
14. A retainer ring for holding a peripheral edge portion of a workpiece to be polished in a top ring for pressing the workpiece against a polishing surface and bringing the workpiece into sliding contact with the polishing surface, said retainer ring comprising:
a first ring member made of resin;
a second ring member made of metal or ceramic; and
a fastening tool for fastening said first ring member and said second ring member in a manner such that said first ring member and said second ring member can be detached as two layers in a vertical direction.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US11/797,721 US20070212988A1 (en) | 2003-07-16 | 2007-05-07 | Polishing apparatus |
Applications Claiming Priority (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2003275406A JP2005034959A (en) | 2003-07-16 | 2003-07-16 | Polishing device and retainer ring |
JP2003-275406 | 2003-07-16 | ||
PCT/JP2004/010364 WO2005007342A1 (en) | 2003-07-16 | 2004-07-14 | Polishing apparatus |
Related Child Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US11/797,721 Division US20070212988A1 (en) | 2003-07-16 | 2007-05-07 | Polishing apparatus |
Publications (1)
Publication Number | Publication Date |
---|---|
US20060128286A1 true US20060128286A1 (en) | 2006-06-15 |
Family
ID=34074551
Family Applications (2)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US10/562,877 Abandoned US20060128286A1 (en) | 2003-07-16 | 2004-07-14 | Polishing apparatus |
US11/797,721 Abandoned US20070212988A1 (en) | 2003-07-16 | 2007-05-07 | Polishing apparatus |
Family Applications After (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US11/797,721 Abandoned US20070212988A1 (en) | 2003-07-16 | 2007-05-07 | Polishing apparatus |
Country Status (4)
Country | Link |
---|---|
US (2) | US20060128286A1 (en) |
JP (1) | JP2005034959A (en) |
TW (1) | TWI283617B (en) |
WO (1) | WO2005007342A1 (en) |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20090111362A1 (en) * | 2007-10-29 | 2009-04-30 | Ebara Corporation | Polishing Apparatus |
US20130196573A1 (en) * | 2012-01-31 | 2013-08-01 | Ebara Corporation | Substrate holder, polishing apparatus, and polishing method |
US9597771B2 (en) * | 2013-12-19 | 2017-03-21 | Taiwan Semiconductor Manufacturing Co., Ltd. | Carrier head having retainer ring, polishing system including the carrier head and method of using the polishing system |
Families Citing this family (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2008023603A (en) * | 2006-07-18 | 2008-02-07 | Nippon Seimitsu Denshi Co Ltd | Retainer ring of two-layer structure |
JP2008093810A (en) * | 2006-10-16 | 2008-04-24 | Shin Etsu Handotai Co Ltd | Retainer ring, polishing head and polishing device |
JP2008229790A (en) * | 2007-03-22 | 2008-10-02 | Nec Electronics Corp | Retainer ring and polishing device |
KR101055002B1 (en) * | 2008-12-11 | 2011-08-05 | 한상효 | Retainer Ring for CMP Device |
JP5505713B2 (en) * | 2010-04-26 | 2014-05-28 | 株式会社Sumco | Polishing liquid distributor and polishing apparatus provided with the same |
JP6403981B2 (en) * | 2013-11-13 | 2018-10-10 | 株式会社荏原製作所 | Substrate holding device, polishing device, polishing method, and retainer ring |
KR102173323B1 (en) * | 2014-06-23 | 2020-11-04 | 삼성전자주식회사 | Carrier head, chemical mechanical polishing apparatus and wafer polishing method |
JP6449194B2 (en) * | 2015-05-25 | 2019-01-09 | 株式会社荏原製作所 | Polishing device, polishing head, and retainer ring |
JP7287761B2 (en) * | 2018-07-31 | 2023-06-06 | 株式会社荏原製作所 | Bearing radius determination method for spherical bearings |
CN113829233B (en) * | 2021-08-21 | 2023-07-18 | 浙江晶盛机电股份有限公司 | Polishing carrier |
Citations (15)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5205082A (en) * | 1991-12-20 | 1993-04-27 | Cybeq Systems, Inc. | Wafer polisher head having floating retainer ring |
US5679065A (en) * | 1996-02-23 | 1997-10-21 | Micron Technology, Inc. | Wafer carrier having carrier ring adapted for uniform chemical-mechanical planarization of semiconductor wafers |
US5695392A (en) * | 1995-08-09 | 1997-12-09 | Speedfam Corporation | Polishing device with improved handling of fluid polishing media |
US5795215A (en) * | 1995-06-09 | 1998-08-18 | Applied Materials, Inc. | Method and apparatus for using a retaining ring to control the edge effect |
US5916412A (en) * | 1996-02-16 | 1999-06-29 | Ebara Corporation | Apparatus for and method of polishing workpiece |
US5931725A (en) * | 1996-07-30 | 1999-08-03 | Tokyo Seimitsu Co., Ltd. | Wafer polishing machine |
US5993302A (en) * | 1997-12-31 | 1999-11-30 | Applied Materials, Inc. | Carrier head with a removable retaining ring for a chemical mechanical polishing apparatus |
US6024630A (en) * | 1995-06-09 | 2000-02-15 | Applied Materials, Inc. | Fluid-pressure regulated wafer polishing head |
US6077385A (en) * | 1997-04-08 | 2000-06-20 | Ebara Corporation | Polishing apparatus |
US6251215B1 (en) * | 1998-06-03 | 2001-06-26 | Applied Materials, Inc. | Carrier head with a multilayer retaining ring for chemical mechanical polishing |
US20010011003A1 (en) * | 2000-02-01 | 2001-08-02 | Minoru Numoto | Structure of polishing head of polishing apparatus |
US6432258B1 (en) * | 1995-10-09 | 2002-08-13 | Ebara Corporation | Apparatus for and method of polishing workpiece |
US20020155797A1 (en) * | 2001-04-19 | 2002-10-24 | Kuo Chia-Ming | Retaining ring of a wafer carrier |
US6585850B1 (en) * | 1999-10-29 | 2003-07-01 | Applied Materials Inc. | Retaining ring with a three-layer structure |
US6840845B2 (en) * | 2001-11-19 | 2005-01-11 | Tokyo Seimitsu Co., Ltd. | Wafer polishing apparatus |
Family Cites Families (28)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP3341258B2 (en) * | 1992-11-27 | 2002-11-05 | 株式会社東芝 | Polishing equipment |
JP3158934B2 (en) * | 1995-02-28 | 2001-04-23 | 三菱マテリアル株式会社 | Wafer polishing equipment |
US5951368A (en) * | 1996-05-29 | 1999-09-14 | Ebara Corporation | Polishing apparatus |
JPH10150009A (en) * | 1996-11-20 | 1998-06-02 | Sony Corp | Wafer polishing device |
JPH10230455A (en) * | 1997-02-17 | 1998-09-02 | Nec Corp | Polishing device |
JP3693459B2 (en) * | 1997-04-08 | 2005-09-07 | 株式会社荏原製作所 | Polishing device |
EP0881039B1 (en) * | 1997-05-28 | 2003-04-16 | Tokyo Seimitsu Co.,Ltd. | Wafer polishing apparatus with retainer ring |
JP3006568B2 (en) * | 1997-12-04 | 2000-02-07 | 日本電気株式会社 | Wafer polishing apparatus and polishing method |
GB2347102B (en) * | 1998-10-16 | 2002-12-11 | Tokyo Seimitsu Co Ltd | Wafer polishing apparatus and polishing quantity detection method |
JP2000218522A (en) * | 1999-01-28 | 2000-08-08 | Ebara Corp | Polishing device |
US6354907B1 (en) * | 1999-03-11 | 2002-03-12 | Ebara Corporation | Polishing apparatus including attitude controller for turntable and/or wafer carrier |
US6241593B1 (en) * | 1999-07-09 | 2001-06-05 | Applied Materials, Inc. | Carrier head with pressurizable bladder |
JP2001071255A (en) * | 1999-09-02 | 2001-03-21 | Mitsubishi Materials Corp | Polishing head |
US6602114B1 (en) * | 2000-05-19 | 2003-08-05 | Applied Materials Inc. | Multilayer retaining ring for chemical mechanical polishing |
EP1177859B1 (en) * | 2000-07-31 | 2009-04-15 | Ebara Corporation | Substrate holding apparatus and substrate polishing apparatus |
US6540590B1 (en) * | 2000-08-31 | 2003-04-01 | Multi-Planar Technologies, Inc. | Chemical mechanical polishing apparatus and method having a rotating retaining ring |
JP2002079459A (en) * | 2000-09-06 | 2002-03-19 | Toshiba Mach Co Ltd | Polishing device |
JP3627143B2 (en) * | 2000-10-23 | 2005-03-09 | 株式会社東京精密 | Wafer polishing equipment |
JP3922887B2 (en) * | 2001-03-16 | 2007-05-30 | 株式会社荏原製作所 | Dresser and polishing device |
JP4686043B2 (en) * | 2001-03-16 | 2011-05-18 | 日新製鋼株式会社 | Winding shaft of strip edge scrap winding device |
TWI261009B (en) * | 2001-05-02 | 2006-09-01 | Hitoshi Suwabe | Polishing machine |
JP2002355753A (en) * | 2001-05-30 | 2002-12-10 | Sumitomo Osaka Cement Co Ltd | Retainer ring of high performance and long life, and polishing device comprising the same |
US6579151B2 (en) * | 2001-08-02 | 2003-06-17 | Taiwan Semiconductor Manufacturing Co., Ltd | Retaining ring with active edge-profile control by piezoelectric actuator/sensors |
JP4049579B2 (en) * | 2001-12-12 | 2008-02-20 | 株式会社荏原製作所 | Substrate holding device and polishing device |
JP4013187B2 (en) * | 2001-12-20 | 2007-11-28 | 株式会社Sumco | Waxless mount polishing machine |
US6835125B1 (en) * | 2001-12-27 | 2004-12-28 | Applied Materials Inc. | Retainer with a wear surface for chemical mechanical polishing |
TWI243083B (en) * | 2002-09-27 | 2005-11-11 | Komatsu Denshi Kinzoku Kk | Polishing apparatus, polishing head, and polishing method |
US7048621B2 (en) * | 2004-10-27 | 2006-05-23 | Applied Materials Inc. | Retaining ring deflection control |
-
2003
- 2003-07-16 JP JP2003275406A patent/JP2005034959A/en active Pending
-
2004
- 2004-07-14 US US10/562,877 patent/US20060128286A1/en not_active Abandoned
- 2004-07-14 WO PCT/JP2004/010364 patent/WO2005007342A1/en active Application Filing
- 2004-07-15 TW TW093121079A patent/TWI283617B/en active
-
2007
- 2007-05-07 US US11/797,721 patent/US20070212988A1/en not_active Abandoned
Patent Citations (16)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5205082A (en) * | 1991-12-20 | 1993-04-27 | Cybeq Systems, Inc. | Wafer polisher head having floating retainer ring |
US5795215A (en) * | 1995-06-09 | 1998-08-18 | Applied Materials, Inc. | Method and apparatus for using a retaining ring to control the edge effect |
US6652368B2 (en) * | 1995-06-09 | 2003-11-25 | Applied Materials, Inc. | Chemical mechanical polishing carrier head |
US6024630A (en) * | 1995-06-09 | 2000-02-15 | Applied Materials, Inc. | Fluid-pressure regulated wafer polishing head |
US5695392A (en) * | 1995-08-09 | 1997-12-09 | Speedfam Corporation | Polishing device with improved handling of fluid polishing media |
US6432258B1 (en) * | 1995-10-09 | 2002-08-13 | Ebara Corporation | Apparatus for and method of polishing workpiece |
US5916412A (en) * | 1996-02-16 | 1999-06-29 | Ebara Corporation | Apparatus for and method of polishing workpiece |
US5679065A (en) * | 1996-02-23 | 1997-10-21 | Micron Technology, Inc. | Wafer carrier having carrier ring adapted for uniform chemical-mechanical planarization of semiconductor wafers |
US5931725A (en) * | 1996-07-30 | 1999-08-03 | Tokyo Seimitsu Co., Ltd. | Wafer polishing machine |
US6077385A (en) * | 1997-04-08 | 2000-06-20 | Ebara Corporation | Polishing apparatus |
US5993302A (en) * | 1997-12-31 | 1999-11-30 | Applied Materials, Inc. | Carrier head with a removable retaining ring for a chemical mechanical polishing apparatus |
US6251215B1 (en) * | 1998-06-03 | 2001-06-26 | Applied Materials, Inc. | Carrier head with a multilayer retaining ring for chemical mechanical polishing |
US6585850B1 (en) * | 1999-10-29 | 2003-07-01 | Applied Materials Inc. | Retaining ring with a three-layer structure |
US20010011003A1 (en) * | 2000-02-01 | 2001-08-02 | Minoru Numoto | Structure of polishing head of polishing apparatus |
US20020155797A1 (en) * | 2001-04-19 | 2002-10-24 | Kuo Chia-Ming | Retaining ring of a wafer carrier |
US6840845B2 (en) * | 2001-11-19 | 2005-01-11 | Tokyo Seimitsu Co., Ltd. | Wafer polishing apparatus |
Cited By (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20090111362A1 (en) * | 2007-10-29 | 2009-04-30 | Ebara Corporation | Polishing Apparatus |
US8100743B2 (en) | 2007-10-29 | 2012-01-24 | Ebara Corporation | Polishing apparatus |
US20130196573A1 (en) * | 2012-01-31 | 2013-08-01 | Ebara Corporation | Substrate holder, polishing apparatus, and polishing method |
US9662764B2 (en) * | 2012-01-31 | 2017-05-30 | Ebara Corporation | Substrate holder, polishing apparatus, and polishing method |
TWI639485B (en) * | 2012-01-31 | 2018-11-01 | 日商荏原製作所股份有限公司 | Substrate holding device, polishing device, and polishing method |
TWI674171B (en) * | 2012-01-31 | 2019-10-11 | 日商荏原製作所股份有限公司 | Substrate holding device, polishing device, and polishing method |
US9597771B2 (en) * | 2013-12-19 | 2017-03-21 | Taiwan Semiconductor Manufacturing Co., Ltd. | Carrier head having retainer ring, polishing system including the carrier head and method of using the polishing system |
US20170182628A1 (en) * | 2013-12-19 | 2017-06-29 | Taiwan Semiconductor Manufacturing Co., Ltd. | Carrier head having retainer ring, polishing system including the carrier head and method of using the polishing system |
US10377013B2 (en) * | 2013-12-19 | 2019-08-13 | Taiwan Semiconductor Manufacturing Co., Ltd. | Carrier head having retainer ring, polishing system including the carrier head and method of using the polishing system |
US11458587B2 (en) * | 2013-12-19 | 2022-10-04 | Taiwan Semiconductor Manufacturing Company, Ltd. | Carrier head having retainer ring, polishing system including the carrier head and method of using the polishing system |
Also Published As
Publication number | Publication date |
---|---|
TWI283617B (en) | 2007-07-11 |
US20070212988A1 (en) | 2007-09-13 |
JP2005034959A (en) | 2005-02-10 |
TW200514649A (en) | 2005-05-01 |
WO2005007342A1 (en) | 2005-01-27 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US20070212988A1 (en) | Polishing apparatus | |
US7357699B2 (en) | Substrate holding apparatus and polishing apparatus | |
US7850509B2 (en) | Substrate holding apparatus | |
US5964653A (en) | Carrier head with a flexible membrane for a chemical mechanical polishing system | |
US7108581B2 (en) | Polishing apparatus | |
EP1092504B1 (en) | Apparatus and method for polishing workpiece | |
US10442056B2 (en) | Substrate holding apparatus and polishing apparatus | |
JP5216542B2 (en) | Retaining ring for chemical mechanical polishing head | |
US7445543B2 (en) | Polishing apparatus | |
US20050054272A1 (en) | Polishing method | |
EP0835723A1 (en) | A carrier head with a layer of conformable material for a chemical mechanical polishing system | |
KR100419135B1 (en) | Apparatus and method for chemical-mechanical polishing (cmp) using a head having direct pneumatic wafer polishing pressure system |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AS | Assignment |
Owner name: EBARA CORPORATION, JAPAN Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:NABEYA, OSAMU;TOGAWA, TETSUJI;REEL/FRAME:017434/0832 Effective date: 20051118 |
|
STCB | Information on status: application discontinuation |
Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION |