Top ring and substrate polishing apparatus

Abstract

To provide a top ring or a substrate polishing apparatus capable of making a polishing profile more uniform on the central side of a square substrate and the outer edge side of the substrate.SOLUTION: A top ring for holding a polygonal substrate includes: a base member which is connected to a rotation shaft; a substrate suction member which includes a substrate suction body that has a substrate suction surface for suctioning the substrate and communicates with a decompression module, a shielding member that is configured to cover the side of the substrate suction body opposite to the substrate suction surface, and a frame member that is connected to the shielding member so as to surround at least a portion of the periphery of the base member; and a biasing mechanism which has a first end in contact with the base member and a second end in contact with the frame member, and applies a biasing force in a direction that brings the base member and the frame member close to each other or separates them from each other.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] This application relates to a top ring and a substrate polishing apparatus.

Background Art

[0002] In the manufacture of semiconductor devices, a chemical mechanical polishing (CMP) apparatus is used to planarize the surface of a substrate. Substrates used in the manufacture of semiconductor devices are often disk-shaped. In addition to semiconductor devices, the requirement for flatness when planarizing the surface of square substrates such as CCL substrates (Copper Clad Laminate substrates), PCB (Printed Circuit Board) substrates, photomask substrates, and display panels is also increasing. In addition, the requirement for planarizing the surface of a package substrate on which electronic devices such as PCB substrates are arranged is also increasing.

[0003] The substrate polishing apparatus includes a top ring for holding the substrate. For example, as described in Patent Document 1, the top ring includes a rotation axis, a flange connected to the rotation axis, a suction plate fitted into an opening formed on the lower surface of the flange, and a shielding plate attached to the upper surface of the suction plate. This top ring is configured to suck the substrate through the suction plate by vacuum suction and press the substrate against the polishing pad by applying pressure to the shielding plate.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] In the above-described top ring, a difference in the film thickness of the substrate after the polishing process was observed between the central side and the outer edge side of the substrate. In particular, when polishing a rectangular substrate, the polishing amount at the corners of the substrate may be smaller than that at the central portion of the substrate. This is presumably because when the top ring presses the substrate through the shielding plate, a force in the direction of warping upward is generated at the corners of the substrate, and the pressing force at the corners of the substrate becomes lower than that at the central portion of the substrate. Further, as shown in FIG. 10, in the substrate polishing apparatus 1000, the polishing slurry PS is supplied from the passage 353 (opening 355) formed in the polishing table 350 to the center of the rectangular substrate WF held by the top ring 302, and the polishing slurry PS may be supplied to the outer edge side of the substrate WF by diffusing along the plate surface of the substrate WF to the outer edge side (see the dashed-dotted arrow). In this process, the supply amount of the polishing slurry PS may be less at the corners of the substrate than at the central side of the substrate, and there is a possibility that the polishing amount at the corners of the substrate is lower than that at the central portion of the substrate. Also, depending on the polishing environment, the polishing amount on the outer edge side of the rectangular substrate may be larger than that on the central side of the substrate.

[0006] In view of the above circumstances, one object of the present application is to provide a top ring or a substrate polishing apparatus capable of making the polishing profile more uniform between the central side and the outer edge side of a rectangular substrate.

Means for Solving the Problems

[0007] According to one embodiment, a top ring for holding a polygonal substrate is proposed. The top ring includes a base member connected to a rotating shaft, a substrate adsorbing body having a substrate adsorbing surface for adsorbing the substrate and communicating with a decompression module, a shielding member configured to shield the surface of the substrate adsorbing body opposite to the substrate adsorbing surface, and a frame member connected to the shielding member so as to surround at least a part of the periphery of the base member, and a substrate adsorbing member including the frame member, a first end in contact with the base member, and a second end in contact with the frame member, and a biasing mechanism for applying a biasing force in a direction of bringing the base member and the frame member closer to each other or separating them. ​

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

[0009] Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the drawings described below, the same or corresponding components are denoted by the same reference numerals, and redundant descriptions are omitted.

[0010] FIG. 1 is a plan view showing the overall configuration of a substrate polishing apparatus 1000 according to an embodiment. The substrate polishing apparatus 1000 shown in FIG. 1 includes a load unit 100, a transfer unit 200, a polishing unit 300, a drying unit 500, and an unload unit 600. In the illustrated embodiment, the transfer unit 200 has two transfer units 200A and 200B, and the polishing unit 300 has two polishing units 300A and 300B. Note that one or three or more transfer units 200 and polishing units 300 may be provided. In one embodiment, these units can be formed independently. By forming these units independently, a substrate polishing apparatus 1000 having a different configuration can be easily formed by arbitrarily combining the number of each unit. Further, the substrate polishing apparatus 1000 includes a controller 900, and each component of the substrate polishing apparatus 1000 is controlled by the controller 900. In one embodiment, the controller 900 can be configured from a general computer including an input / output device, an arithmetic device, a storage device (storage medium) 900a, and the like. The controller 900 functions as the main body of the operation for controlling the substrate polishing apparatus 1000. The controller 900 performs various processes by reading and executing a program stored in the storage device 900a or the like. The program may be acquired from a recording medium such as a DVD-ROM or acquired via a network.

[0011] <Load unit> The load unit 100 is a unit for introducing a substrate WF before processing such as polishing and cleaning into the substrate polishing apparatus 1000. In one embodiment, the load unit 100 is configured to comply with the mechanical device interface standard (IPC-SMEMA-9851) of the Surface Mount Equipment Manufacturers Association (SMEMA).

[0012] In the illustrated embodiment, the transport mechanism of the load unit 100 includes a plurality of transport rollers 202 and a plurality of roller shafts 204 to which the transport rollers 202 are attached. In the embodiment shown in FIG. 1, three transport rollers 202 are attached to each roller shaft 204. The substrate WF is placed on the transport rollers 202, and the substrate WF is transported as the transport rollers 202 rotate. The attachment position of the transport rollers 202 on the roller shaft 204 can be arbitrary as long as the substrate WF can be stably transported. However, since the transport rollers 202 contact the substrate WF, it is preferable to arrange the transport rollers 202 so that they contact an area where there is no problem even when they contact the substrate WF that is the substrate WF to be processed. In one embodiment, the transport rollers 202 of the load unit 100 can be made of a conductive polymer. In one embodiment, the transport rollers 202 are electrically grounded via the roller shafts 204 and the like. This is to prevent the substrate WF from being damaged due to charging. Also, in one embodiment, an ionizer (not shown) may be provided in the load unit 100 to prevent the charging of the substrate WF.

[0013] <Transport Unit> The substrate polishing apparatus 1000 shown in FIG. 1 includes two transport units 200A and 200B. Since the two transport units 200A and 200B can have the same configuration, they will be collectively described as the transport unit 200 below.

[0014] The illustrated transport unit 200 includes a plurality of transport rollers 202 for transporting the substrate WF. By rotating the transport rollers 202, the substrate WF on the transport rollers 202 can be transported in a predetermined direction. The transport rollers 202 of the transport unit 200 may be formed of a conductive polymer or a non-conductive polymer.

[0015] In one embodiment, the transfer unit 200 has a cleaning nozzle 284. The cleaning nozzle 284 is connected to a cleaning liquid supply source (not shown). The cleaning nozzle 284 is configured to supply the cleaning liquid to the substrate WF conveyed by the transfer roller 202.

[0016] <Polishing unit> FIG. 2 is a perspective view schematically showing the configuration of a polishing unit 300 according to one embodiment. The substrate polishing apparatus 1000 shown in FIG. 1 includes two polishing units 300A and 300B. Since the two polishing units 300A and 300B can have the same configuration, hereinafter, they will be collectively described as the polishing unit 300.

[0017] As shown in FIG. 2, the polishing unit 300 includes a polishing table 350 and a top ring 302 that constitutes a polishing head for holding the substrate to be polished and pressing it against the polishing surface on the polishing table 350. The polishing table 350 is connected to a polishing table rotation motor (not shown) disposed below it via a table shaft 351 and is rotatable around the table shaft 351. A polishing pad 352 is attached to the upper surface of the polishing table 350, and the surface 352a of the polishing pad 352 constitutes a polishing surface for polishing the substrate.

[0018] Above the polishing table 350, a polishing liquid supply nozzle 354 is installed, and the polishing liquid supply nozzle 354 supplies the polishing liquid onto the polishing pad 352 on the polishing table 350. Also, as shown in FIG. 2, the polishing table 350 and the table shaft 351 are provided with a passage 353 for supplying the polishing liquid. The passage 353 communicates with an opening 355 on the surface of the polishing table 350. At a position corresponding to the opening 355 of the polishing table 350, the polishing pad 352 is formed with a through hole 357, and the polishing liquid passing through the passage 353 is supplied to the surface of the polishing pad 352 from the opening 355 of the polishing table 350 and the through hole 357 of the polishing pad 352. Note that the opening 355 of the polishing table 350 and the through hole 357 of the polishing pad 352 may be one or more, or may not be provided. Also, the positions of the opening 355 of the polishing table 350 and the through hole 357 of the polishing pad 352 are arbitrary, but in one embodiment, they are arranged near the center of the polishing table 350. Note that in one embodiment, during the polishing of the substrate, the substrate WF held by the top ring 302 is moved (so as to cover the through hole 357) so as to pass near the center of the polishing table 350 (see FIG. 10).

[0019] Although not shown in FIG. 2, in one embodiment, the polishing unit 300 includes an atomizer 358 for jetting a liquid or a mixed fluid of a liquid and a gas toward the polishing pad 352 (see FIG. 1). The liquid jetted from the atomizer 358 is, for example, pure water, and the gas is, for example, nitrogen gas.

[0020] The top ring 302 is connected to the top ring shaft 18, and this top ring shaft 18 is adapted to move up and down with respect to the swing arm 360 by the vertical movement mechanism 319. Due to the up and down movement of this top ring shaft 18, the entire top ring 302 is moved up and down with respect to the swing arm 360 for positioning. The top ring shaft 18 is adapted to rotate by the drive of a top ring rotation motor (not shown). Due to the rotation of the top ring shaft 18, the top ring 302 is adapted to rotate about the top ring shaft 18.

[0021] The top ring 302 is adapted to hold a rectangular substrate on its lower surface. In this embodiment, the "rectangular substrate" means a substrate having a plate surface of a triangle, a quadrilateral, or a polygon with five or more sides. The swing arm 360 is configured to be rotatable about the support shaft 362. The top ring 302 is movable between the substrate transfer position of the above-described transfer unit 200 and above the polishing table 350 by the rotation of the swing arm 360. By lowering the top ring shaft 18, the top ring 302 can be lowered to press the substrate against the surface (polishing surface) 352a of the polishing pad 352. At this time, the top ring 302 and the polishing table 350 are rotated respectively, and polishing liquid is supplied onto the polishing pad 352 from the polishing liquid supply nozzle 354 provided above the polishing table 350 and / or from the opening 355 provided in the polishing table 350. In this way, the substrate can be pressed against the polishing surface 352a of the polishing pad 352 to polish the surface of the substrate. As described above, during the polishing of the substrate WF, the arm 360 may be fixed or swung so that the top ring 302 passes through the center of the polishing pad 352 (covers the through hole 357 of the polishing pad 352) (see FIG. 10).

[0022] The vertical movement mechanism 319 for moving the top ring shaft 18 and the top ring 302 up and down includes a bridge 28 that rotatably supports the top ring shaft 18 via a bearing 321, a ball screw 32 attached to the bridge 28, a support base 29 supported by a support column 130, and an AC servo motor 38 provided on the support base 29. The support base 29 that supports the servo motor 38 is fixed to a swing arm 360 via the support column 130.

[0023] The ball screw 32 includes a screw shaft 32a connected to the servo motor 38 and a nut 32b that engages with the screw shaft 32a. The top ring shaft 18 is configured to move up and down integrally with the bridge 28. Therefore, when the servo motor 38 is driven, the bridge 28 moves up and down via the ball screw 32, and thereby the top ring shaft 18 and the top ring 302 move up and down.

[0024] The polishing unit 300 according to one embodiment includes a dressing unit 356 for dressing the polishing surface 352a of the polishing pad 352. This dressing unit 356 includes a dresser 50 that is in sliding contact with the polishing surface 352a, a dresser shaft 51 to which the dresser 50 is connected, an air cylinder 53 provided at the upper end of the dresser shaft 51, and a swing arm 55 that rotatably supports the dresser shaft 51. The lower part of the dresser 50 is constituted by a dressing member 50a, and needle-shaped diamond particles are attached to the lower surface of this dressing member 50a. The air cylinder 53 is disposed on a support base 57 supported by support columns 56, and these support columns 56 are fixed to the swing arm 55.

[0025] The swing arm 55 is driven by a motor (not shown) to swing about a support shaft 58 It is configured as follows. The dresser shaft 51 rotates by the drive of a motor (not shown), and due to the rotation of the dresser shaft 51, the dresser 50 rotates around the dresser shaft 51. The air cylinder 53 moves the dresser 50 up and down via the dresser shaft 51, and presses the dresser 50 against the polishing surface 352a of the polishing pad 352 with a predetermined pressing force.

[0026] The dressing of the polishing surface 352a of the polishing pad 352 is performed as follows. The dresser 50 is pressed against the polishing surface 352a by the air cylinder 53, and at the same time, pure water is supplied to the polishing surface 352a from a pure water supply nozzle (not shown). In this state, the dresser 50 rotates around the dresser shaft 51 and the swing arm 55 swings on the polishing surface 352a, bringing the lower surface (diamond particles) of the dressing member 50a into sliding contact with the rotating polishing surface 352a. In this way, the polishing pad 352 is scraped off by the dresser 50, and the polishing surface 352a is dressed.

[0027] <Drying Unit> The drying unit is a device for drying the substrate WF. In the substrate polishing apparatus 1000 shown in FIG. 1, the drying unit 500 dries the substrate WF that has been polished by the polishing unit 300 and then washed by the washing unit of the transfer unit 200. As shown in FIG. 1, the drying unit 500 is arranged downstream of the transfer unit 200. The drying unit 500 has a nozzle 530 for injecting a gas toward the substrate WF being conveyed on the transfer roller 202. The gas can be, for example, compressed air or nitrogen. By blowing off the water droplets on the conveyed substrate WF by the drying unit 500, the substrate WF can be dried.

[0028] <Unloading Unit> The unloading unit 600 is a unit for carrying out the substrate WF after processes such as polishing and cleaning out of the substrate polishing apparatus 1000. In the substrate polishing apparatus 1000 shown in FIG. 1, the unloading unit 600 receives the substrate after being dried by the drying unit 500. As shown in FIG. 1, the unloading unit 600 is arranged downstream of the drying unit 500. In one embodiment, the unloading unit 600 is configured to comply with the mechanical device interface standard (IPC - SMEMA - 9851) of the SMEMA (Surface Mount Equipment Manufacturers Association).

[0029] <Top Ring> Next, the top ring 302 in the polishing unit 300 according to one embodiment will be described. FIGS. 3 and 4 are a cross - sectional view and a cross - sectional perspective view schematically showing the top ring 302 of one embodiment. As shown in FIGS. 3 and 4, the top ring 302 includes a base member 301 connected to the top ring shaft (rotating shaft) 18. As a specific example, the base member 301 includes a flange 303 connected to the top ring shaft 18, a spacer 304 attached to the lower surface of the flange 303, an upper guide member 305 attached to the lower surface of the spacer 304, and a lower guide member 306 provided on the lower surface of the upper guide member 305. The flange 303, the spacer 304, and the upper guide member 305 are fixed by bolts (not shown). The upper guide member 305 and the lower guide member 306 are fixed by bolts (not shown) with an elastic member 340 sandwiched therebetween. The elastic member 340 can be formed of a rubber material such as silicone rubber, EPDM (ethylene propylene diene rubber), FKM (fluororubber), but is not limited thereto. The lower guide member 306 is provided in a frame shape at the peripheral edge of the lower surface of the upper guide member 305.

[0030] Also, the top ring 302 includes a substrate suction member 330 for sucking the back surface of the substrate WF with the surface to be polished facing downward. The substrate suction member 330 is below the base member 301 It is configured. The substrate adsorption member 330 includes a substrate adsorbent 334. The substrate adsorbent 334 may be a member that can vacuum-adsorb the substrate WF by evacuation using a decompression module (vacuum source) 31. The substrate adsorbent 334 can be composed of a resin porous material (porous material) in which a large number of pores are formed in a resin such as PE (polyethylene), PP (polypropylene), PTFE (polytetrafluoroethylene), or PVC (polyvinyl chloride). In the present embodiment, the substrate adsorbent 334 is formed in a plate shape, and its lower surface defines a substrate adsorption surface 334a for adsorbing the substrate WF.

[0031] Further, the substrate adsorption member 330 includes a shielding member 332. The shielding member 332 may be an airtight member that can shield the flow of gas, and can be formed of a resin plate such as relatively soft PE (polyethylene), PP (polypropylene), PTFE (polytetrafluoroethylene), or PVC (polyvinyl chloride), for example. In the present embodiment, the shielding member 332 is formed so as to shield the surface 334b on the side opposite to the substrate adsorption surface 334a of the substrate adsorbent 334. Further, a suction passage 312 is formed in the shielding member 332 so as to communicate with the surface 334b or the side surface 334c of the substrate adsorbent 334.

[0032] The shielding member 332 of this embodiment includes a frame-shaped elastic seal member 336 that covers the side surface 334c of the substrate adsorber 334. The elastic seal member 336 may be attached to the main body of the shielding member 332 by any means such as a double-sided tape, for example. The elastic seal member 336 may be any member that has elasticity and can shield the flow of gas. For example, as the elastic seal member 336, a soft member having chemical resistance, good stretchability, and a skin surface can be used. For example, as the elastic seal member 336, a silicone sponge, a silicone rubber, or a norseal made of soft polyvinyl chloride can be adopted. In the examples shown in FIGS. 3 and 4, the elastic seal member 336 has a lip portion that extends outward from the lower end. However, it is not limited to such examples, and the elastic seal member 336 may have, for example, a rectangular cross section or a circular cross section. Further, the shielding member 332 may not have the elastic seal member 336 and may be formed to shield the side surface 334c of the substrate adsorber 334.

[0033] By providing the shielding member 332, when the substrate adsorber 334 is evacuated by the decompression module (vacuum source) 31, a negative pressure can be efficiently formed on the substrate adsorption surface 334a. As a result, the substrate WF can be reliably adsorbed to the substrate adsorption member 330, so that even if a retainer member is not provided around the substrate WF, it is possible to prevent the substrate WF from popping out (slipping out) during polishing. Further, when the shape of the substrate WF is square, there is also a risk that the corner portion of the substrate WF contacts the retainer member during polishing and the substrate WF or the top ring is damaged. On the other hand, according to this embodiment, since the substrate WF can be pressed against the polishing pad 352 while being vacuum-adsorbed by the substrate adsorption member 330, it is possible to prevent the substrate WF from slipping out during polishing and to prevent the substrate WF or the top ring from being damaged during polishing.

[0034] As shown in Figs. 3 and 4, the substrate suction member 330 includes a frame member 344 provided on the shielding member 332 so as to surround at least a part of the base member 301 (specifically, the upper guide member 305 and the lower guide member 306). The frame member 344 includes a lower frame member 343 provided in a frame shape on the peripheral portion of the upper surface of the shielding member 332, a frame-shaped upper frame member 342 provided on the lower frame member 343, and a stopper 346 provided on the upper frame member 342. As an example, the shielding member 332 and the frame member 344 are fixed by bolts (not shown). The upper frame member 342 and the lower frame member 343 are connected with an elastic member 340 sandwiched therebetween.

[0035] FIG. 5 is a perspective view showing a substrate suction member according to an embodiment of the present invention, and FIG. 6 is a perspective view showing the substrate suction member according to the embodiment of the present invention. 5 and 6 are enlarged views of a region AA in the substrate 301. For ease of understanding, an upper guide member 305 of a base member 301 is also shown in Fig. 5 and Fig. 6. As shown in Fig. 5, in this embodiment, suction ports 314 are provided at four positions on a substrate suction member 330. Each suction port 314 is connected to a decompression module 31 (not shown) via a suction path 312 and a suction connector 311.

[0036] As shown in FIGS. 5 and 6, the upper frame member 342 includes stoppers 346 provided at the four corners of the upper frame member 342. The stopper 346 is configured to connect different locations of the upper frame member 342 in an arch shape across the inside of the frame. In this embodiment, the stopper 346 is configured to connect two sides forming the corner of the upper frame member 342 in an arch shape. On the other hand, the upper guide member 305 in the base member 301 includes pads 309 provided at the four corners of the upper guide member 305. The pad 309 is provided at a position corresponding to the stopper 346. The pad 309 is formed in a disk shape at the corner of the upper frame member 342 at a height position different from that of the stopper 346. The stopper 346 and the pad 309 overlap each other in a predetermined region when the top ring 302 is viewed in plan (viewed from a direction perpendicular to the substrate adsorption surface 334a). Therefore, the movement of the substrate adsorption member 330 in the height direction can be restricted by the contact between the stopper 346 and the pad 309. The pad 309 is an example of a "contact portion" that restricts the movement in the height direction with respect to the base member 301 by coming into contact with the stopper 346.

[0037] Referring to FIG. 3 again, the top ring 302 includes an elastic membrane 320 configured to form a pressure chamber for pressing the substrate WF between the base member 301 and the substrate adsorption member 330. In the present embodiment, the elastic membrane 320 includes a plurality of elastic membranes 320-1, 320-2, 320-3 having different areas and being laminated. Each of the elastic membranes 320-1, 320-2, 320-3 includes a central portion that contacts the upper surface of the shielding member 332 and an end portion that extends from the central portion and is fixed to different positions on the lower surface of the upper guide member 305. A plurality of concentric pressure chambers for pressing the substrate WF are formed between the base member 301 and the plurality of elastic membranes 320-1, 320-2, 320-3 by the plurality of elastic membranes 320-1, 320-2, 320-3. Each of the plurality of pressure chambers communicates with a pressure adjustment unit (fluid supply source) 30 via a pressure passage 313. The pressure adjustment unit 30 has a pressure adjustment function of adjusting the pressure of the pressure fluid supplied to each pressure chamber. By forming the plurality of pressure chambers, the pressing force of the substrate WF against the polishing pad 352 via the substrate adsorption member 330 can be controlled for each area. According to the present embodiment, the substrate WF is adsorbed to the substrate adsorption surface 334a by making the substrate adsorber 334 negative pressure using the decompression module 31, and the substrate WF can be pressed against the polishing pad 352 via the substrate adsorption member 330 by pressurizing the pressure chamber by the pressure adjustment unit 30. Note that the top ring 302 is not limited to having a plurality of concentric pressure chambers formed therein, and may have a plurality of pressure chambers divided in the circumferential direction formed therein. Further, the elastic membrane 320 is not limited to being configured by laminating a plurality of sheets, and may have a partition wall that divides a plurality of pressure chambers. As an example, an elastic membrane formed by a mold as disclosed in Japanese Patent No. 7074606 may be used. Further, the top ring 302 may have a single pressure chamber formed therein without having the elastic membrane 320.

[0038] As shown in FIGS. 3 and 4, the top ring 302 includes a biasing mechanism 400 configured to bias the frame member 344 of the substrate adsorption member 330 in the vertical direction. The biasing mechanism 400 of the present embodiment is constituted by a pneumatic actuator. Specifically, the biasing mechanism 400 includes a cylinder 401 attached to the base member 301, a diaphragm 408 disposed within the cylinder 401, and a piston 410 that contacts the frame member 344. The cylinder 401 is defined by an upper cylinder housing 402 attached to the lower surface of the outer peripheral portion of the flange 303 of the base member 301 and a lower cylinder housing 404 attached to the lower surface of the upper cylinder housing 402. The upper cylinder housing 4 02 and the lower cylinder housing 404 are formed of polyphenylene sulfide (PPS) resin as an example. The diaphragm 408 is formed of a rubber material as an example and is sandwiched and fixed between the upper cylinder housing 402 and the lower cylinder housing 404. The internal space of the cylinder 401 is partitioned into an upper space and a lower space by the diaphragm 408. The piston 410 is disposed in the lower space of the cylinder 401. The upper end of the piston 410 contacts the lower surface of the diaphragm 408, and the lower end of the piston 410 protrudes from the lower side of the lower cylinder housing 404 and contacts the frame member 344. In one embodiment, the piston 410 is formed of a resin such as PPS resin, metal, or ceramic. Forming the piston 410 of resin is advantageous in that the weight can be reduced.

[0039] In one embodiment, the top ring 302 includes a plurality of biasing mechanisms 400. As an example, each of the plurality of biasing mechanisms 400 may be provided near a corner of the rectangular substrate WF. However, the biasing mechanism 400 is not limited to being provided near all corners of the rectangular substrate WF, and may be provided near some corners. Also, one end (the second end) of the biasing mechanism 400 may contact the stopper 346 in the frame member 344. As an example, the piston 410 may be configured to contact a region 346a (a plurality of locations for each stopper 346) hatched in FIG. 6. However, the present invention is not limited to such an example, and one end (the second end) of the biasing mechanism 400 may be configured to directly contact the upper frame member 342 instead of or in addition to the stopper 346. FIG. 7 is a diagram showing the contact location of the biasing mechanism 400 in a modified example. As shown in FIG. 7, one end (the second end) of the biasing mechanism 400 may be configured to contact a hatched region 342a in the upper frame member 342 as an example. In other words, the biasing mechanism 400 may be configured to contact a region closer to the corner than the stopper 346, or may be configured to contact the upper frame member 342 near the stopper 346. Note that the end (the first end) of the biasing mechanism 400 that contacts the base member 301 and the end (the second end) that contacts the frame member 344 are preferably separated from the pressure chamber formed by the elastic film 320 and / or the substrate adsorber 334 when the top ring 302 is viewed in plan (seen from a direction perpendicular to the substrate adsorption surface 334a).

[0040] As shown in FIGS. 3 and 4, the upper cylinder housing 402 communicates with the pressure adjusting unit 30 via the pressure passage 413. By using the pressure adjusting unit 30 for pressing the substrate WF as the drive source in the biasing mechanism 400 in this way, the number of components of the top ring 302 can be reduced. However, the top ring 302 may have a pressure supply source as a drive source separately from the pressure adjusting unit 30 for pressing the substrate WF. When the working fluid (e.g., air, nitrogen) is supplied from the pressure adjusting unit 30 into the upper space of the cylinder 401, the diaphragm 408 bulges downward and moves the piston 410 downward. When the piston 410 moves downward, the frame member 344 can be biased downward.

[0041] In one embodiment, as shown in FIG. 3, the top ring 302 further includes a band 345 that connects the outer side surface of the base member 301 and the outer side surface of the frame member 344. In the example shown in FIG. 3, the band 345 is specifically attached from the outer side surface of the upper cylinder housing 402 to the outer side surface of the upper frame member 342. The band 345 allows displacement of the substrate suction member 330 with respect to the base member 301 and prevents the entry of polishing liquid or the like into the space between the substrate suction member 330 and the base member 301.

[0042] Such a top ring 302 can evacuate the substrate suction body 334 by the decompression module (vacuum source) 31 and adsorb the substrate WF to the substrate suction surface 334a. Then, by pressurizing the pressure chamber by the pressure adjusting unit 30, the substrate WF can be pressed against the polishing pad 352 via the substrate suction member 330. At this time, the controller 900 may control the pressure supply to the pressure chamber so that the film thickness distribution of the substrate WF becomes the target distribution. As an example, the controller 900 is based on a recipe determined in advance based on the characteristics of the substrate WF and the like. Further, the pressure adjustment unit 30 may be controlled. Also, a sensor for measuring the film thickness of the substrate WF may be provided in the substrate polishing apparatus 1000, and the controller 900 may acquire information from the sensor during substrate polishing and control the pressure adjustment unit 30 based on the acquired information. Note that, as the sensor for measuring the film thickness of the substrate WF, an eddy current sensor, an optical sensor, or a microwave sensor can be adopted. Further, the controller 900 may correct the control of the pressure adjustment unit 30 thereafter based on the polishing profile of the substrate WF after polishing.

[0043] Also, the top ring 302 of the present embodiment can press the substrate WF against the polishing pad 352 by urging the frame member 344 of the substrate suction member 330 by the urging mechanism 400 separately from the pressing of the substrate suction body 334 by the elastic film 320. Thereby, it is possible to adjust the polishing amount of the outer edge portion of the substrate WF where a difference in polishing amount is likely to occur compared to the central portion of the substrate WF, and it is possible to make the polishing profiles uniform between the central side and the outer edge side of the rectangular substrate. Specifically, the controller 900 may control the urging force by the urging mechanism 400 based on a recipe determined in advance so that the film thickness distribution of the substrate WF becomes a target distribution. Also, a sensor for measuring the film thickness of the substrate WF may be provided in the substrate polishing apparatus 1000, and the controller 900 may acquire information from the sensor during substrate polishing and control the urging mechanism 400 based on the acquired information. Further, the controller 900 may correct the control of the urging mechanism 400 thereafter based on the polishing profile of the substrate WF after polishing.

[0044] <Modification 1> FIG. 8 is a cross-sectional view schematically showing a top ring in a modified example. The top ring 302A of the modified example is generally the same as the above-described top ring 302 except that it includes a biasing mechanism 400A different from the biasing mechanism 400, and redundant descriptions are omitted. The biasing mechanism 400A of the modified example is constituted by an elastic body 410A. As the elastic body 410A, various known elastic bodies such as a coil spring can be adopted. In the top ring 302A of the modified example, a lower flange 404A is attached to the lower surface of the flange 303 of the base member 301. Also, collars 406A and 408A are fixed to the lower flange 404A of the base member 301 and the frame member 344. One end (first end) of the elastic body 410A is attached to the collar 406A, and the other end (second end) of the elastic body 410A is attached to the collar 408A. In such a top ring 302A of the modified example, the base member 301 and the frame member 344 are biased by inserting the compressed elastic body 410A between the lower flange 404A (collar 406A) and the upper frame member 342 (collar 408A). The biasing force by the biasing mechanism 400A using the elastic body 410A is determined by the relative distance between the lower flange 404A (collar 406A) of the base member 301 and the upper frame member 342 (collar 408A). And by selecting the elastic body 410A or adjusting the amount of compressive deformation of the elastic body 410A in advance by experiments or simulations, etc., the biasing force for biasing the frame member 344 toward the polishing table 350 can be adjusted. Thereby, similar to the top ring 302 of the embodiment, the top ring 302A of the modified example can adjust the pressing force on the polishing table 350 at the outer edge portion of the substrate WF to adjust the polishing amount at the outer edge portion of the substrate WF, and can make the polishing profile uniform between the central side and the outer edge side of the rectangular substrate. The biasing mechanism 400A may be configured to be changeable, as an example, the elastic body 410A to an elastic body having a desired elastic modulus. Also, the biasing mechanism 400A may be configured such that the positions of the collars 406A and 408A in the height direction can be adjusted using a spacer or the like. In the example shown in FIG. 8, the elastic body 410A is attached to the lower flange 404A of the base member 301 and the upper frame member 342 of the frame member 344, but is not limited to such an example.As an example, the elastic body 410A may be attached to the flange 303 of the base member 301 or may be attached to the stopper 346 of the frame member 344.

[0045] <Modification Example 2> In the above-described Modification Example 1, the biasing mechanism 400A biases the frame member 344 away from the base member 301, i.e., in the direction of pressing the substrate WF, and biases the frame member 344 and the base member 301. However, when the polishing amount of the outer edge portion of the substrate WF is larger than the polishing amount of the central portion, the biasing mechanism 400A may be configured to apply a biasing force in the direction of bringing the frame member 344 closer to the base member 301.

[0046] <Modification Example 3> FIG. 9 is a diagram showing an example of a portion of the frame member 344 where the piston 410 or the elastic body 410A contacts. In the above-described embodiments and modification examples, the pistons 410 or the elastic bodies 410A of the plurality of biasing mechanisms 400, 400A are provided so as to contact the corner region AC, which is a region near the corners of the rectangular substrate WF, i.e., a region including the corners of the frame member 344. However, the present invention is not limited to such an example, and the biasing mechanisms 400, 400A may be provided in the side region (for example, a region including the center of the side and not including the corners) AS of the frame member 344 instead of or in addition to the corner region AC of the frame member 344. Even in such an example, similar to the top ring 302 of the embodiment, the polishing amount of the outer edge portion of the substrate WF can be adjusted, and the polishing profile can be made uniform between the central side and the outer edge side of the rectangular substrate.

[0047] The present invention can also be described in the following forms. [Aspect 1]According to Aspect 1, a top ring for holding a polygonal substrate is proposed. The top ring includes a base member connected to a rotating shaft, a substrate adsorbing body having a substrate adsorbing surface for adsorbing the substrate and communicating with a decompression module, a shielding member configured to shield a surface of the substrate adsorbing body opposite to the substrate adsorbing surface, and a frame member connected to the shielding member so as to surround at least a part of the periphery of the base member, a substrate adsorbing member, a first end in contact with the base member, and a second end in contact with the frame member, and a biasing mechanism for applying a biasing force in a direction of bringing the base member and the frame member closer to each other or separating them. According to Aspect 1, the polishing profile can be made more uniform between the central side and the outer edge side of the square substrate.

[0048] [Aspect 2]According to Aspect 2, in Aspect 1, the biasing mechanism includes a pneumatic actuator having the first end and the second end. According to Aspect 2, by using a pneumatic actuator, the polishing profile can be made more uniform between the central side and the outer edge side of the substrate.

[0049] [Aspect 3]According to Aspect 3, in Aspect 2, the pneumatic actuator has a cylinder attached to the base member and capable of receiving a working fluid therein, a diaphragm disposed in the cylinder, and a piston in contact with the frame member and displaceable in accordance with the movement of the diaphragm.

[0050] [Aspect 4]According to Aspect 4, in Aspect 2 or 3, an elastic membrane configured to form a pressurized chamber between the base member and the shielding member, and a fluid supply source for supplying a working fluid to the pressurized chamber are provided, and the pneumatic actuator is operated by the working fluid from the fluid supply source. According to Aspect 4, a biasing mechanism can be configured by using a fluid supply source for supplying a working fluid to the pressurized chamber, and the number of components can be reduced.

[0051] [Aspect 5] According to Aspect 5, in Aspect 1, the biasing mechanism is an elastic body having the first end portion and the second end portion. According to Aspect 2, by using an elastic body, the polishing profile can be made more uniform between the central side and the outer edge side of the substrate.

[0052] [Aspect 6] According to Aspect 6, in Aspects 1 to 5, the frame member includes stoppers that connect different portions of the frame member in an arch shape across the inside of the frame, the base member has a contact portion that restricts the movement of the substrate suction member in the height direction with respect to the base member by contacting the stopper, and the second end portion of the biasing mechanism contacts the stopper. According to Aspect 6, a biasing mechanism can be configured using a stopper for restricting the movement of the substrate suction member in the height direction.

[0053] [Aspect 7] According to Aspect 7, in Aspects 1 to 6, the second end portion of the biasing mechanism contacts the corner region of the frame member when viewed from a direction perpendicular to the substrate suction surface.

[0054] [Aspect 8] According to Aspect 8, in Aspects 1 to 7, the second end portion of the biasing mechanism contacts the side region of the frame member when viewed from a direction perpendicular to the substrate suction surface.

[0055] [Aspect 9] According to Aspect 9, in Aspects 1 to 8, an elastic film configured to form a pressure chamber between the base member and the shielding member is provided. According to Aspect 9, the pressure chamber can be pressurized to press the substrate held by the top ring.

[0056] [Aspect 10] According to Aspect 10, in Aspect 9, the elastic film is configured to form a plurality of concentric pressure chambers between the base member and the shielding member. According to Aspect 10, the plurality of concentric pressure chambers can be pressurized to press the substrate held by the top ring.

[0057] [Aspect 11] According to Aspect 11, in Aspects 1 to 10, the first end portion and the second end portion are separated from the substrate adsorbing body when viewed from a direction perpendicular to the substrate adsorbing surface.

[0058] [Aspect 12] According to Aspect 12, in Aspects 1 to 11, the substrate adsorbing body is formed of a porous material.

[0059] [Aspect 13] According to Aspect 13, in Aspects 1 to 12, a band is provided that connects the outer side surface of the portion of the base member not surrounded by the frame member and the outer side surface of the frame member.

[0060] [Aspect 14] According to Aspect 14, a substrate polishing apparatus is proposed that includes the top ring according to any one of Aspects 1 to 13 and a table configured to hold a polishing pad. According to Aspect 14, the same effects as those of the above-described aspects can be achieved.

[0061] [Aspect 15] According to Aspect 15, the top ring according to Aspect 9 or 10, a table configured to hold a polishing pad, and a controller that controls the supply of the working fluid to the pressure chamber and the biasing force by the biasing mechanism so that the film thickness distribution of the substrate becomes the target film thickness distribution are provided. A substrate polishing apparatus is proposed. According to Aspect 15, by controlling the supply of the working fluid to the pressure chamber and the biasing force by the biasing force by the controller, the polishing profile can be made more uniform between the central side and the outer edge side of the rectangular substrate.

[0062] The embodiments of the present invention have been described above. However, the above-described embodiments of the invention are for facilitating the understanding of the present invention and do not limit the present invention. The present invention can be changed and improved without departing from the gist thereof, and it goes without saying that equivalents of the present invention are included therein. Also, within the range where at least a part of the above-described problems can be solved, Alternatively, within the range where at least part of the effects are achieved, any combination of the embodiments and modifications is possible, and any combination or omission of each component described in the claims and the specification is possible.

Explanation of Reference Numerals

[0063] 18… Top ring shaft (rotating shaft) 30… Pressure adjustment unit 31… Vacuum reduction module 300… Polishing unit 301… Base member 302… Top ring 309… Pad 320… Elastic membrane 330… Substrate adsorption member 332… Shielding member 334… Substrate adsorber 334a… Substrate adsorption surface 336… Elastic seal member 340… Elastic member 342… Upper frame member 343… Lower frame member 344… Frame member 345… Band 346… Stopper 350… Polishing table 352… Polishing pad 400, 400A… Biasing mechanism 401… Cylinder 402… Upper cylinder housing 404… Lower cylinder housing 406A, 408A… Collar 408… Diaphragm 410… Piston 410A… Elastomer 900… Controller 900a… Memory device 1000… Substrate polishing apparatus WF… Substrate

Claims

1. A top ring for holding a polygonal substrate, comprising: a base member connected to a rotating shaft; a substrate adsorbing member including a substrate adsorbing body having a substrate adsorbing surface for adsorbing the substrate and communicating with a decompression module, a shielding member configured to shield a surface of the substrate adsorbing body opposite to the substrate adsorbing surface, and a frame member connected to the shielding member so as to surround at least a part of the periphery of the base member; a biasing mechanism having a first end in contact with the base member and a second end in contact with the frame member, and applying a biasing force in a direction of approaching or separating the base member and the frame member; The top ring provided with the above.

2. The top ring according to claim 1, wherein the biasing mechanism includes a pneumatic actuator having the first end and the second end.

3. The pneumatic actuator includes: a cylinder attached to the base member and capable of receiving a working fluid therein; a diaphragm disposed within the cylinder; a piston in contact with the frame member and displaceable in accordance with the movement of the diaphragm; The top ring according to claim 2, having the above.

4. an elastic membrane configured to form a pressurized chamber between the base member and the shielding member; a fluid supply source for supplying a working fluid to the pressurized chamber; The pneumatic actuator is actuated by the working fluid from the fluid supply source; The top ring according to claim 2.

5. The top ring according to claim 1, wherein the biasing mechanism is an elastic body having the first end and the second end.

6. The frame member includes stoppers that connect different portions of the frame member in an arch shape across the inside of the frame; The base member has a contact portion that contacts the stopper to limit the movement of the substrate adsorbing member in the height direction with respect to the base member; The second end of the biasing mechanism contacts the stopper; The top ring according to claim 1.

7. The top ring according to claim 1, wherein the second end of the biasing mechanism contacts a corner region of the frame member when viewed from a direction perpendicular to the substrate adsorbing surface.

8. The top ring according to claim 1, wherein the second end of the biasing mechanism contacts a side region of the frame member when viewed from a direction perpendicular to the substrate adsorbing surface.

9. The top ring according to claim 1, comprising an elastic film configured to form a pressure chamber between the base member and the shielding member.

10. The top ring according to claim 9, wherein the elastic film is configured to form a plurality of concentric pressure chambers between the base member and the shielding member.

11. The first end portion and the second end portion are separated from the substrate adsorbent body when viewed from a direction perpendicular to the substrate adsorption surface. The top ring according to claim 1.

12. The top ring according to claim 1, wherein the substrate adsorbent body is formed of a porous material.

13. The top ring according to claim 1, comprising a band connecting an outer side surface of a portion of the base member not surrounded by the frame member and an outer side surface of the frame member.

14. The top ring according to any one of claims 1 to 13, A table configured to hold a polishing pad, A substrate polishing apparatus comprising.

15. The top ring according to claim 9 or 10, A table configured to hold a polishing pad, A controller that controls the supply of the working fluid to the pressure chamber and the biasing force by the biasing mechanism so that the film thickness distribution of the substrate becomes the target film thickness distribution, A substrate polishing apparatus comprising.

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