Carrier head with segmented substrate chuck

Abstract

To provide a carrier head for a chemical mechanical polishing device which can bring a desirable substrate profile that is more uniformly polished.SOLUTION: A carrier head includes a carrier body 104, an outer membrane assembly part 140, a membrane assembly 110, and an inner membrane assembly part 150. The outer membrane assembly part 140 is supported by the carrier body 104, and defines a plurality of first outer chambers 144 which are independently pressurizable. A chuck 160 supported below the outer membrane assembly part 140 includes a plurality of annular rings 162 which are independently movable in a vertical direction by the outer chambers 144 which are independently pressurizable of the outer membrane assembly part 140. The inner membrane assembly part 150 is supported by the carrier body 104, and is surrounded by the innermost ring out of the plurality of concentric rings of the chuck 160. The inner membrane assembly part 150 defines a plurality of second inside chambers 154 which are independently pressurizable, and has a lower surface brought into contact with the substrate.SELECTED DRAWING: Figure 1B

Description

[Technical field]

[0001] The present invention relates to a carrier head for use in chemical mechanical polishing (CMP). [Background technology]

[0002] Integrated circuits are typically formed on a substrate by the successive deposition of conductive, semiconductive, or insulating layers on a semiconductor wafer. Various manufacturing processes require planarization of layers on the substrate. For example, one manufacturing step involves depositing a filler layer over a non-planar surface and planarizing the filler layer. In some applications, the filler layer is planarized until the top surface of the patterned layer is exposed. For example, a metal layer can be deposited on a patterned insulating layer, filling the trenches and holes in the insulating layer. After planarization, the remaining metal in the trenches and holes in the patterned layer forms vias, plugs, and lines to provide conductive paths between thin film circuits on the substrate. As another example, a dielectric layer can be deposited over a patterned conductive layer and then planarized to allow subsequent photolithographic steps to be performed.

[0003] Chemical mechanical polishing (CMP) is an accepted method of planarization. This planarization method typically involves mounting a substrate on a carrier head. The exposed surface of the substrate typically rests against a rotating polishing pad. The carrier head provides a controlled load on the substrate that presses the substrate against the polishing pad. An abrasive slurry, typically in the form of abrasive particles, is applied to the surface of the polishing pad. Summary of the Invention

[0004] In one embodiment, a carrier head for a chemical mechanical polishing apparatus includes a carrier body, an outer membrane assembly, an annular segmented chuck, and an inner membrane assembly. The outer membrane assembly is supported from the carrier body and defines a first plurality of individually pressurizable outer chambers. The annular segmented chuck, supported below the outer membrane assembly, includes a plurality of concentric rings that are independently vertically movable by respective pressurizable chambers of the outer membrane assembly. At least two of the rings have passages for suction-chucking a substrate to the chuck. The inner membrane assembly is supported from the carrier body and is surrounded by an innermost ring of the plurality of concentric rings of the chuck. The inner membrane assembly defines a second plurality of individually pressurizable inner chambers and has a lower surface that contacts the substrate.

[0005] In another aspect, a chemical mechanical polishing system includes a platen supporting a polishing pad, a carrier head, a plurality of pressure sources coupled to an inner chamber and an outer chamber in the carrier head, and a controller coupled to the pressure sources.

[0006] In another aspect, a method of chemical mechanical polishing includes placing a substrate in a carrier head, polishing the substrate using pressure from an outer membrane assembly delivered through a substrate chuck of the carrier head and pressure from an inner membrane assembly of the carrier head surrounded by the chuck, and preventing lateral movement of the substrate during polishing by chucking the substrate to the carrier head using the chuck.

[0007] Implementations may include one or more of the following features.

[0008] The carrier head can include an upper carrier body and a lower carrier body. The edge control ring surrounds an outermost ring of the chuck's concentric rings and can move vertically relative to the outermost ring. The pressurizable chamber can control the positioning of the edge control ring relative to the carrier body. The retaining ring can be connected to the carrier body and can surround the chuck.

[0009] Possible advantages may include, but are not limited to, one or more of the following: A segmented substrate chuck may secure the substrate to the carrier head while simultaneously positioning the substrate against the polishing pad. The chuck may prevent the substrate from moving laterally, thereby eliminating or reducing the possibility of the substrate striking the retaining ring. The life of the retaining ring may be increased as the inner surface of the retaining ring is less susceptible to damage due to reduced contact between the substrate and the retaining ring. Additionally, the edges of the substrate may experience less lateral forces such that the substrate is less likely to warp, resulting in a more uniformly polished desirable substrate profile. [Brief description of the drawings]

[0010] [Figure 1A] 1 is a schematic cross-sectional view of a carrier head with a segmented chuck. [Figure 1B] FIG. 1B is a schematic cross-sectional view of the membrane assembly of FIG. 1A. [Diagram 2] 1 is a schematic cross-sectional view of a carrier head with a segmented chuck and a floating membrane assembly. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] During polishing, frictional forces exerted by the polishing pad on the substrate may cause the substrate to contact the retaining ring. This may damage the retaining ring, for example, scratches may be produced on the inner surface of the wall of the retaining ring due to contact between the substrate and the retaining ring. The substrate may also be shredded or ruined as a result of impact with the retaining ring. Furthermore, as a result of scratches, the edge of the substrate may ride up or slam into the polishing pad during polishing, which may change the pressure distribution on the substrate and cause non-uniformity. Also, the retaining ring may need to be replaced after a certain number of polishing cycles, for example, before non-uniformity induced by scratches exceeds an acceptable limit.

[0012] A technique to address one or more of these issues is to chuck the substrate to a carrier head. Chucking the substrate can keep it from contacting the retaining ring, thereby reducing substrate edge non-uniformity and prolonging the life of the retaining ring. However, the carrier head can also include a flexible membrane that contacts some portion of the backside of the substrate.

[0013] With reference to FIGS. 1A and 1B, a substrate 10 may be polished by a chemical mechanical polishing (CMP) apparatus that includes a carrier head 100 .

[0014] Carrier head 100 includes a housing 102 , a carrier body 104 , a gimbal mechanism 106 (which may be considered part of the carrier body 104 ), and a retaining ring 130 .

[0015] The housing 102 may be generally circular in shape and may be connected to a drive shaft 124 that rotates therewith about a central axis 125 during polishing. There may be a passage through the housing 102 for pneumatic control of the carrier head 100.

[0016] The carrier body 104 is a vertically movable assembly located below the housing 102. A loading chamber 108 is located between the housing 102 and the carrier body 104 such that the carrier body 104 is subjected to a load, e.g., a downward pressure or a downward weight. The chamber 108 may be sealed by an annularly curved rolling diaphragm or bellows 109. The vertical position of the carrier body 104 relative to the polishing pad is also controlled by the loading chamber 108, which can be pressurized to move the carrier body 104 vertically. In some implementations, the vertical position of the carrier head 100 relative to the polishing pad is controlled by an actuator (not shown) capable of vertically moving a drive shaft 124.

[0017] The gimbal mechanism 106 allows the carrier body 104 to pivot and move vertically relative to the housing 102 while preventing lateral movement of the base assembly 104 relative to the housing 102. However, the gimbal mechanism is an optional feature and the base assembly may be at a fixed incline relative to the housing 102.

[0018] The membrane assembly 110 includes an inner membrane assembly 150 and an outer membrane assembly 140. The inner membrane assembly 150 includes an inner membrane 152 connected to the carrier body 104. The inner membrane 152 may be constructed of a thin, flexible material such as silicone rubber. A lower surface 155 of the inner membrane 150 provides a substrate mounting surface, and the substrate 10 directly contacts the lower surface 155 when pressed into the carrier head 100.

[0019] The inner membrane 152 may divide the space between the carrier body 104 and the lower surface 155 into a number of individually pressurizable inner chambers 154. The pressurizable inner chambers 154 may be arranged, for example, concentrically about the axis 125. The central inner chamber 154a may be circular and the other inner chambers 154b may be annular. There may be between 1 and 10 individually pressurizable inner chambers 154. Each individually pressurizable inner chamber 154 may be pressurized to inflate and depressurized to deflate independently of the other individually pressurizable inner chambers 154.

[0020] In some implementations, the inner membrane 152 can include flaps 152a (see FIG. 1A ) that divide the space into individually pressurizable inner chambers 154. Alternatively, in some implementations, each individually pressurizable inner chamber 154 can be defined by a floor 151 of the inner membrane 152 and two sidewalls 153. In each chamber, a flange 156 can extend inwardly from an upper edge of the sidewalls 153 and be secured to the carrier body 104 by a clamp 157 (see FIG. 1B ). The clamp 157 can be secured to the carrier body 104 by a screw, bolt, or other similar fastener.

[0021] The sidewalls 153 of adjacent inner chambers may be connected at their upper edges by a bridging portion 159, e.g., flush with the flange portion 156. However, below the bridging portion 159, adjacent sidewalls 153 are separated by a gap 158. The separation of the sidewalls 153 allows each individually pressurizable inner chamber 154 to expand relative to the adjacent individually pressurizable inner chamber 154 (e.g., the floor 151 of each individually pressurizable inner chamber 154 moves vertically). Thus, the use of separate sidewalls 153 for adjacent inner chambers reduces pressure crosstalk between adjacent zones on the substrate.

[0022] The inner membrane assembly 150 is surrounded by an outer membrane assembly 140. The outer membrane assembly 140 includes an outer membrane 142, which is connected to the carrier body 104. The outer membrane 142 may be constructed of a thin, flexible material, such as silicone rubber. The outer membrane 142 divides the space between the carrier body 104 and the lower surface 145 into a number of individually pressurizable outer chambers 144. Each outer chamber 144 controls the pressure applied to a portion of the substrate chuck 160, such as one of the annular rings 162 of the chuck 160 as described below.

[0023] The individually pressurizable outer chambers 144 may be annular concentric chambers. There may be between 2 and 10 individually pressurizable outer chambers 144. Each individually pressurizable outer chamber 144 may be pressurized to expand and depressurized to deflate independently of the other outer chambers 144.

[0024] In some implementations, the outer membrane 142 includes flaps 142a that divide the space beneath the carrier body 104 into multiple individually pressurizable outer chambers 144. Alternatively, in some implementations, each individually pressurizable outer chamber 144 may be bounded by a floor 141 and two sidewalls 143 of the outer membrane 142. In each chamber, a flange 146 may extend inwardly from an upper edge of the sidewalls 143 and be secured to the carrier body 104 by a clamp 147 (see FIG. 1B). A clamp 157 may be secured to the carrier body 104 by a screw, bolt, or other similar fastener.

[0025] The sidewalls 143 of adjacent outer chambers may be connected at their upper edges by a bridging portion 149, e.g., flush with the flange portion 146. However, below the bridging portion 149, adjacent sidewalls 143 are separated by a gap 148. The separation of the sidewalls 143 allows each individually pressurizable outer chamber 144 to expand relative to the adjacent outer chamber 144 (e.g., the floor 151 of each individually pressurizable outer chamber 144 moves vertically). Thus, the use of separate sidewalls 143 for adjacent inner chambers reduces pressure crosstalk between adjacent zones on the substrate. In some implementations, the inner membrane 152 and the outer membrane 154 are part of one single membrane.

[0026] During a polishing operation, the individually pressurizable chambers 144 and 154 can be pressurized to expand and increase the polishing rate for the portion of the substrate 10 underlying the individually pressurizable chamber 144 or 154. Similarly, the individually pressurizable chambers 144 or 154 can be depressurized to deflate and decrease the polishing rate for the portion of the substrate 10 underlying the individually pressurizable chamber 144 or 145.

[0027] Beneath the outer membrane assembly 140 is a segmented substrate chuck 160 that surrounds the inner membrane assembly 150. The chuck 160 may be constructed from aluminum, stainless steel, ceramic, or plastic. The chuck 160 may include a plurality of concentric annular rings 162. The annular rings 162 may be concentric with the axis of rotation 125 of the carrier head 100. There may be an equal number of annular rings 162 and outer chambers 144. Each annular ring 162 of the chuck 160 may be positioned beneath a corresponding outer chamber 144. Thus, as each outer chamber 144 expands or deflates, it causes the underlying annular ring 162 to move vertically, exerting more or less pressure on the substrate 10.

[0028] Between adjacent annular rings 162 are channels 164, e.g., annular gaps. The channels 164 may be connected to a pressure source 180 (discussed further below). The pressure source 180 may blow polishing by-products (e.g., polishing slurry, particles) from between the annular rings 162.

[0029] Because the chuck 160 supports the outer membrane assembly 140, the membrane 142 does not contact the substrate 10 during the polishing operation and is not subject to increased wear or tear due to contact with the substrate 10.

[0030] Beneath the chuck 160, and possibly also beneath the inner membrane portion 150, may be a cushion 170. The cushion 170 may be made of a compressible material, such as rubber, such as silicone, Ethylene Propylene Diene Terpolymer (EPDM) or a fluoroelastomer, or a porous polymer sheet. The cushion 170 may include a portion 172 beneath the annular ring 162 of the chuck and a portion 175 beneath the inner membrane 152.

[0031] One or more vacuum channels 174 are formed through the cushion 170. Specifically, the channels 174 may be formed through the cushion in the area below the annular ring 172. The vacuum channels 174 may be connected to a pressure source 180 via passages 182 to modulate the pressure within the vacuum channels 174. A portion of each passage 182 may be provided by a conduit 184 running through the annular ring 162 of the chuck 160 (other portions of the passages 182 are shown generally for simplicity, but may include conduits through other solid portions and hoses through the chamber). For example, the pressure source 180 may create a vacuum in the vacuum channels 174 that may hold the substrate 10 down against the cushion 170.

[0032] The cushion 170 supports the chuck 160 and the inner membrane assembly 150, thereby addressing non-uniformities introduced by the chuck 160 and the inner membrane assembly 150. The gaps between the annular rings 162 and the gaps 158 between the individually pressurizable chambers 154 are not pressurized and may result in local non-uniformities in the applied pressure. However, the cushion 170 may span the gaps between the annular rings 162 and the gaps 158. In this manner, the cushion 170 may distribute the pressure applied to a portion of the substrate 10 and smooth out non-uniformities that may occur in the portion of the substrate 10 that supports the gaps between the annular rings 162 and the gaps 158 between the individually pressurizable chambers 154.

[0033] Alternatively, the cushion 170 may be constructed from separate annular rings, with each ring of the cushion 170 separated from adjacent rings by a gap and secured to the bottom of a corresponding annular ring 162 of the chuck 160. The cushion 170 may also include a central region 175 that spans the inner membrane portion 150.

[0034] The membrane assembly 100 and the substrate 10 can be surrounded by the retaining ring 130, and the retaining ring 130 can act as a pressure control ring. The retaining ring 130 can be connected to an actuator 134, for example, a pressurizable chamber or bellows. The actuator 134 can cause the retaining ring 130 to move vertically. For example, the actuator 134 can press the retaining ring 130 against the polishing pad 30 during a polishing operation. The retaining ring 130 is configured to surround the substrate 10 on the polishing pad 30 without contacting the substrate 10, as the substrate 10 is held in place within the retaining ring 130 by the chuck 160. This can increase the life of the retaining ring 130. That is, by reducing the contact of the substrate 10 that is held in place within the retaining ring 130 but not pressed against the retaining ring 130, the substrate 10 and the retaining ring 130 can be less damaged.

[0035] The vacuum pressure holds the substrate 10 against the cushion 170, thereby preventing lateral movement of the substrate 10 within the carrier head 100. As a result, the edge of the substrate 10 is less susceptible to damage due to the impact of impact contact between the substrate 10 and the retaining ring 130. Similarly, by reducing contact between the substrate 10 and the retaining ring 130, the inner surface of the retaining ring 130 is less susceptible to damage. Also, because the retaining ring 130 is less susceptible to damage from the substrate 10, the life of the retaining ring 130 before it needs to be replaced may be extended. Also, because the edge of the substrate 10 is less likely to be pulled upwards or downwards due to contact with the retaining ring 130, polishing may be more uniform, especially near the edge of the substrate. Additionally, because the cushion 170 is between the substrate 10 and the inner membrane assembly 150, the membrane 152 is not subject to increased wear or tear due to contact with the substrate 10 during the polishing operation.

[0036] A controller 190 may be connected to a pressure source 180, which may be, for example, a pump, facility air, or a vacuum supply line with associated valves. The pressure source 180 may be connected to the loading chamber 108, the channel 164, and the vacuum channel 174 to increase or decrease their pressures. For example, the controller 190 may control the pressure source 180 to pressurize the loading chamber 108 to lower the carrier body 104 toward the polishing pad 30, or to depressurize the vacuum channel 174 to evacuate and attach the substrate 10 to the cushion 170.

[0037] 2, carrier head 200 includes housing 102, upper carrier body 204a, lower carrier body 204b, retaining ring 130, and outer ring 230. Carrier head 200 is similar to carrier head 100 except as noted below.

[0038] The upper carrier body 204a is a vertically movable assembly located below the housing 102. An upper loading chamber 208a is located between the housing 102 and the upper carrier body 204a such that the upper carrier body 204a is subjected to a load, i.e., downward pressure or weight. The vertical position of the upper carrier body 204a relative to the polishing pad 30 is controlled by the upper loading chamber 208a, which is pressurizable to move the upper carrier body 204a vertically. The upper loading chamber 208a may be sealed by an annular curved rolling diaphragm or bellows 224 that extends between the housing 102 and the upper carrier body 204a.

[0039] Similarly, the lower carrier body 204b is a vertically movable assembly located below the upper carrier body 204a. A lower loading chamber 208b is located between the upper carrier body 204a and the lower carrier body 204b such that the lower carrier body 204b is subjected to a load, i.e., a downward pressure or a downward weight. The vertical position of the lower carrier body 204b relative to the polishing pad is also controlled by the lower loading chamber 208b, which is pressurizable to move the lower carrier body 204b vertically. The controller 190 can increase or decrease the pressure in the upper load zone 208a and the lower load zone 208b by adjusting the pressure source 180.

[0040] The upper and lower carrier bodies 204a, 204b can move independently of one another, for example, as determined by the pressures in the upper and lower loading chambers 208a, 208b. The lower loading chamber 208a can be sealed by an annular, curved, rolling diaphragm or bellows 250 that extends between the upper and lower carrier bodies 204a, 204b.

[0041] For example, the diaphragm 250 can enable vertical movement of the upper and lower carrier bodies 204a and 204b by flexibly connecting the upper carrier body 204a to the lower carrier body 204b. The diaphragm 250 can be a flexible and impermeable material, such as rubber. The diaphragm 250 can be secured to the upper and lower carrier bodies 204a and 204b using fasteners 252a and 252b. An inner edge of the diaphragm 250 can be sandwiched between the fastener 252a and the upper carrier body 204a. Fasteners such as bolts, screws, or other similar fasteners can be used to secure the fastener 252a to the upper carrier body 204a. Similarly, an outer edge of the diaphragm 250 can be sandwiched between the fastener 252b and the lower carrier body 204b. Fasteners such as bolts, screws, or other similar fasteners can be used to secure the fastener 252b to the lower carrier body 204b.

[0042] In some implementations, the vertical position of the upper and lower carrier bodies 204a, 204b relative to the polishing pad is controlled by an actuator (not shown) capable of moving the shaft 122 vertically.

[0043] An annular retaining ring 130 may be connected to an actuator and / or bellows 234. The actuator and / or bellows 234 may allow the retaining ring 130 to move vertically. For example, the actuator and / or bellows 234 may press the retaining ring 130 against the polishing pad 30 during a polishing operation. The retaining ring 130 is configured to enclose the substrate 10 over the polishing pad 30 without contacting the substrate 10 as the substrate 10 is held in place within the retaining ring 130 by the chuck 160.

[0044] An outer ring 230 may surround the retaining ring 130. The outer ring 230 may be connected to the upper carrier body 204a by fasteners, such as bolts, screws, or other similar fasteners. The outer ring 230 provides for positioning or referencing of the carrier head 200 relative to the surface of the polishing pad 30.

[0045] Surrounding the chuck 160 is an edge control ring 240. The edge control ring 240 may be separate from the lower loading chamber 208b and connected to the lower carrier body 204b. For example, a rolling diaphragm or bellows 244 may be positioned between the edge control ring 240 and a lip 242 extending from the lower carrier body 204b. The edge control ring 240 is positioned over the edge of the substrate 10 to independently polish the edge of the substrate 10 and allow targeted edge loading to control polishing of the edge of the substrate 10 surrounding the area on the substrate 10 controlled by the chuck 160.

[0046] The controllers and other computing device portions of the systems described herein may be implemented in digital electronic circuitry, or in computer software, firmware, or hardware. For example, a controller may include a processor that executes a computer program product, such as a computer program stored in a non-transitory machine-readable storage medium. Such computer programs (also known as programs, software, software applications, or code) may be written in any form of programming language, including compiled or interpreted languages, and the computer programs may be deployed in any form, including as stand-alone programs or as modules, components, subroutines, or other units suitable for use in a computing environment.

[0047] Although the specification contains many specific implementation details, these should not be considered as limitations on the scope of any invention or what may be claimed, but as delineations of features specific to particular embodiments of a particular invention. Certain features described herein in the context of separate embodiments may be implemented in combination in only one embodiment. Conversely, various features described in the context of only one embodiment may be implemented in multiple embodiments separately or in any suitable subcombination. Also, although features may be described above as acting in a combination and may even be initially claimed as such, one or more features from a claimed combination may, in some cases, be excluded from the combination, and the claimed combination may be directed to a subcombination or a variation of the subcombination.

[0048] Although several embodiments of the present invention have been described, it will be understood that various modifications may be made without departing from the spirit and scope of the invention. Accordingly, other implementations are within the scope of the following claims.

Claims

1. 1. A carrier head for a chemical mechanical polishing apparatus, comprising: A carrier body; an outer membrane assembly supported from the carrier body, the outer membrane assembly defining a first plurality of individually pressurizable outer chambers; an annular segmented chuck supported from the outer membrane assembly, the substrate chuck including a plurality of concentric rings independently vertically movable by respective pressurizable chambers of the outer membrane assembly, at least two of the rings having passages for suction-chucking a substrate to the chuck; a carrier head comprising: an inner membrane assembly supported from the carrier body, the inner membrane assembly being surrounded by an innermost ring of the plurality of concentric rings of the chuck, defining a second plurality of individually pressurizable inner chambers, and having a lower surface in contact with the substrate.

2. The carrier head of claim 1 , further comprising a cushion extending beneath the substrate chuck, the cushion secured to the substrate chuck and configured to contact the substrate.

3. The carrier head of claim 2 , wherein the cushion is comprised of concentric rings.

4. The carrier head of claim 2 , wherein the cushion includes a vacuum channel aligned with the passage through the ring.

5. The carrier head of claim 2 , wherein the cushion spans a gap between adjacent concentric rings of the substrate chuck.

6. The carrier head of claim 2 , wherein the cushion extends beneath the inner membrane assembly.

7. The carrier head of claim 6 , wherein the cushion spans a plurality of individually pressurizable chambers of the inner membrane assembly.

8. The carrier head of claim 1 , wherein the inner membrane assembly includes an inner membrane having a plurality of flaps that divide a space beneath the carrier body into the plurality of inner chambers.

9. The carrier head of claim 8 , wherein the outer membrane assembly includes an outer membrane having a plurality of flaps that divide a space beneath the carrier body into the plurality of outer chambers.

10. The carrier head of claim 9 , wherein the inner membrane and the outer membrane are part of a single membrane.

11. a platen supporting the polishing pad; A carrier head, Carrier body, an outer membrane assembly supported from the carrier body, the outer membrane assembly defining a first plurality of individually pressurizable outer chambers; an annular segmented substrate chuck supported from the outer membrane assembly, the annular segmented substrate chuck including a plurality of concentric rings independently vertically movable by respective pressurizable chambers of the outer membrane assembly, at least two of the rings having passages for vacuum chucking a substrate to the chuck; a carrier head including an inner membrane assembly supported from the carrier body, the inner membrane assembly being surrounded by an innermost ring of the plurality of concentric rings of the chuck, defining a second plurality of individually pressurizable chambers, the inner membrane assembly having a lower surface in contact with the substrate; a plurality of pressure sources coupled to the inner chamber and the outer chamber; and a controller connected to the pressure source.

12. 12. The system of claim 11, further comprising a cushion extending beneath the substrate chuck, the cushion secured to the substrate chuck and configured to contact the substrate.

13. The system of claim 12 , wherein the cushion includes a vacuum channel aligned with the passage through the ring and connected to the pressure source.

14. 12. The system of claim 11, wherein the carrier head includes an edge control ring that surrounds an outermost ring of the plurality of concentric rings of the chuck and is vertically movable relative to the outermost ring.

15. 1. A method of chemical mechanical polishing comprising the steps of: Placing the substrate in a carrier head; polishing the substrate using pressure from an outer membrane assembly delivered through a substrate chuck of the carrier head and pressure from an inner membrane assembly of the carrier head surrounded by the chuck; and preventing lateral movement of the substrate during polishing by chucking the substrate to the carrier head using the chuck.

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