Elastic film, polishing head, and polishing method

Abstract

The invention provides an elastic film capable of improving elasticity, a polishing head, and a polishing method. The elastic film (100) has a pressing portion (101) and a partition wall (102) having a bulging structure.

Description

Technical Field

[0001] The invention relates to an elastic film, a grinding head and a grinding method. Background Art

[0002] In recent semiconductor device manufacturing, the precision required for each process has reached the order of several nanometers, and chemical mechanical polishing (CMP) is no exception. In addition, with the high integration of semiconductor integrated circuits, miniaturization and multi-layering are accelerating.

[0003] Therefore, in order to realize these miniaturization and multilayering, in CMP polishing, it is required to control the deviation of the film thickness after CMP polishing to a deviation of several nanometers over the entire surface of the wafer.

[0004] The main reason for the deviation of the remaining film thickness is the deviation of the film formation of the wafer. For example, the process of forming a film on the wafer is performed using various film forming techniques such as plating, chemical vapor deposition (CVD), and physical vapor deposition (PVD). In these film forming techniques, the film is sometimes not formed uniformly over the entire surface of the wafer. In addition, in recent years, there are cases where the thickness and shape of the wafer itself vary, and it is required to flatten such a wafer by a CMP process.

[0005] Prior art literature

[0006] Patent Literature

[0007] Patent Document 1: Japanese Patent Application Publication No. 2005-223322

[0008] Conventional polishing heads can independently vary the pressing force along the radial direction of the wafer, and thus can control the film thickness profile in the radial direction of the wafer. However, since the pressure chambers are arranged concentrically, it is impossible to control the pressing force along the circumference of the wafer, and it is impossible to control the film thickness profile in the circumferential direction. In this regard, a method of dividing the pressure chambers in the circumferential direction may also be considered.

[0009] When a pressure chamber formed by an elastic membrane composed of an elastic member commonly used in a CMP device is pressurized, the elastic membrane expands and comes into close contact with the wafer. With such a structure, the elastic membrane can evenly transmit the pressure in the pressure chamber to the wafer.

[0010] However, the elastic membrane has a plurality of partition walls for forming divided pressure chambers, and such an elastic membrane is difficult to expand and contract, especially near the partition walls, and may not be able to uniformly transmit the pressure in the pressure chamber to the wafer. Summary of the invention

[0011] Therefore, an object of the present invention is to provide an elastic film and a polishing head capable of improving stretchability.

[0012] An object of the present invention is to provide a polishing method using an elastic film capable of improving stretchability.

[0013] In one embodiment, an elastic film applicable to a polishing head for polishing a substrate is provided. The elastic film has a pressing portion for pressing the substrate and a partition wall having a bulging structure for forming a pressurizing chamber for applying a pressing force to the pressing portion.

[0014] In one embodiment, the partition wall includes a first wall portion and a second wall portion that form the bulging structure, and the first wall portion and the second wall portion include wide width portions that are separated from each other and a sandwich portion that is connected to the wide width portions and close to each other.

[0015] In one embodiment, the partition wall includes a first wall portion and a second wall portion having a V-shaped cross-sectional shape approaching each other toward the pressing portion, and the first wall portion and the second wall portion are connected to each other at the pressing portion.

[0016] In one embodiment, the partition wall has a first wall portion, a second wall portion, and a third wall portion, wherein the first wall portion, the second wall portion, and the third wall portion have a Y-shaped cross-sectional shape, and the third wall portion is connected to the first wall portion and the second wall portion, and extends from the connection portion connected to the first wall portion and the second wall portion toward the pressing portion.

[0017] In one embodiment, the partition wall includes a first pressure chamber and a second pressure chamber disposed on both sides of the pressurizing chamber, and the pressurizing chamber is disposed above the first pressure chamber and the second pressure chamber.

[0018] In one embodiment, the elastic film has a peripheral wall constituting an outer shape of the elastic film, and the partition wall has a peripheral wall side wall portion disposed adjacent to the peripheral wall and extending obliquely with respect to the pressing portion.

[0019] In one aspect, there is provided a polishing head including the elastic film and a head body that holds the elastic film.

[0020] In one embodiment, the head main body includes a partition wall holder that holds the partition wall, and at least a portion of the partition wall holder is disposed in the pressurization chamber.

[0021] In one embodiment, the polishing head has a widthwise gap formed between the partition wall and the partition wall holder.

[0022] In one embodiment, a polishing method is provided, wherein the substrate is held by an elastic membrane that presses the substrate, and while the substrate is held, a fluid is supplied to a pressure chamber formed by a pressing portion that presses the substrate to press the substrate against a polishing pad, and a fluid is supplied to a pressurized chamber formed by a partition wall having a bulge structure to apply a pressing force to the pressing portion.

[0023] In one embodiment, the step of holding the substrate includes supplying a fluid to the pressurizing chamber and creating a vacuum in the pressurizing chamber to form a suction space on a lower surface of the pressing portion, thereby sucking the substrate.

[0024] In one embodiment, the polishing method includes the step of forming a vacuum in the pressure chamber and supplying a fluid to the pressure chamber after polishing of the substrate is completed, thereby detaching the substrate from the elastic film.

[0025] In one embodiment, the partition wall includes a first wall portion and a second wall portion that form the bulging structure, and the first wall portion and the second wall portion include wide width portions that are separated from each other and a sandwich portion that is connected to the wide width portions and close to each other.

[0026] In one embodiment, the partition wall includes a first wall portion and a second wall portion having a V-shaped cross-sectional shape approaching each other toward the pressing portion, and the first wall portion and the second wall portion are connected to each other at the pressing portion.

[0027] In one embodiment, the partition wall has a first wall portion, a second wall portion, and a third wall portion, wherein the first wall portion, the second wall portion, and the third wall portion have a Y-shaped cross-sectional shape, and the third wall portion is connected to the first wall portion and the second wall portion, and extends from the connection portion connected to the first wall portion and the second wall portion toward the pressing portion.

[0028] In one embodiment, the elastic film has a peripheral wall constituting an outer shape of the elastic film, and the partition wall has a peripheral wall side wall portion disposed adjacent to the peripheral wall and extending obliquely with respect to the pressing portion.

[0029] Effects of the Invention

[0030] The partition wall has a bulging structure forming a pressurized chamber. With such a structure, the elastic film can improve its stretchability, especially the stretchability of the pressed part. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is a schematic diagram showing one embodiment of the polishing device.

[0032] Figure 2This is an enlarged cross-sectional view showing one embodiment of a polishing head.

[0033] Figure 3 is a top view showing one embodiment of the elastic membrane.

[0034] Figure 4 yes Figure 3 Partial cross-sectional view at line AA.

[0035] Figure 5 yes Figure 3 Partial cross-sectional view at line BB.

[0036] Figure 6 It is a diagram showing another embodiment of the elastic membrane.

[0037] Figure 7 It is a diagram showing another embodiment of the elastic membrane.

[0038] Figure 8 (a) is a diagram showing an example of a partition wall mounted on a partition wall holder, Figure 8 (b) is a diagram showing another example of a partition wall mounted on a partition wall retainer, Figure 8 (c) is a diagram showing a state in which the partition wall attached to the partition wall holder is inclined.

[0039] Fig. 9 It is a figure which shows another embodiment of a partition wall.

[0040] Fig.10 (a) is a diagram showing an embodiment of the peripheral wall of the elastic membrane, Fig.10 (b) is a diagram showing another embodiment of the peripheral wall.

[0041] Fig.11 (a) and Fig.11 (b) is a diagram showing the action of the polishing head sucking and holding the wafer.

[0042] Fig.12 It is a diagram showing another embodiment of the elastic membrane.

[0043] Fig.13 This is a diagram showing the action of the polishing head to detach the wafer.

[0044] Explanation of symbols

[0045] 1 Abrasive pad

[0046] 1a Grinding surface

[0047] 2 Grinding table

[0048] 3 Grinding fluid supply nozzle

[0049] 5 Up and down movement mechanism

[0050] 6 Rotating mechanism

[0051] 7 Swing mechanism

[0052] 10 Control Device

[0053] 10a Storage unit

[0054] 10b Calculation unit

[0055] 12 Arm shaft

[0056] 14 Swing arm

[0057] 14a Supporting platform

[0058] 16 Head shaft

[0059] 20 Swing motor

[0060] 22 Rotating motor

[0061] 23 Rotating drum

[0062] 24 Timing belt

[0063] 25A, 25B bearings

[0064] 30 Up and down movement motor

[0065] 31 Connecting parts

[0066] 32 Rotary joint

[0067] 33 Fluid pipeline

[0068] 36 Pressure regulating device

[0069] 41 Dresser

[0070] 49 Head body

[0071] 53 Flange

[0072] 56 Retaining ring pressing mechanism

[0073] 57 Retaining ring mechanism

[0074] 70 Spacer

[0075] 71 Carrier

[0076] 75 retaining ring

[0077] 76 Rolling Diaphragm

[0078] 77 Fluid pipeline

[0079] 88 Fluid pipeline

[0080] 100 Elastic membrane

[0081] 101 Pressing points

[0082] 102 partition wall (including peripheral wall partition wall)

[0083] 103 Wall

[0084] 110 partition wall retainer

[0085] 110a Flow hole

[0086] 110b Fitting portion

[0087] 120 wall portion (including peripheral wall side wall portion)

[0088] 120A first wall portion

[0089] 120B Second wall

[0090] 120C Third wall

[0091] 125 base end

[0092] 130 Wide Width

[0093] 131 Clamping part

[0094] 131a Protrusion

[0095] PA grinding device

[0096] PH grinding head

[0097] ES Film Thickness Sensor

[0098] SP retaining ring pressure chamber

[0099] CL1 grinding table center axis

[0100] Center axis of CL2 grinding head

[0101] A1 (A1-A~A1-D) pressure chamber

[0102] A2 (A2-A~A2-D) pressure chamber

[0103] A3 (A3-A~A3-D) pressure chamber

[0104] A4 (A4-A~A4-D) pressure chamber

[0105] A5 (A5-A~A5-D) pressure chamber

[0106] MSP Compression Chamber

[0107] H suction hole

[0108] G Width gap

[0109] V Adsorption space

[0110] RN Release nozzle. DETAILED DESCRIPTION

[0111] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In addition, in the accompanying drawings described below, the same or equivalent components are marked with the same symbols and repeated descriptions are omitted. In the multiple embodiments described below, the structure of one embodiment not specifically described is the same as other embodiments, so its repeated description is omitted.

[0112] Figure 1 Schematic diagram showing one embodiment of a grinding device. Figure 1 As shown, the polishing device PA includes: a polishing head PH, which holds and rotates a wafer W as an example of a substrate; a polishing table 2, which supports a polishing pad 1; a polishing liquid supply nozzle 3, which supplies polishing liquid (slurry) to the polishing surface 1a of the polishing pad 1; and a dresser 41, which dresses the polishing surface 1a of the polishing pad 1.

[0113] The grinding table 2 rotates around its central axis CL1. The grinding head PH rotates around its central axis CL2. The grinding table 2 and the grinding head PH rotate in the same direction (see Figure 1 ), in this state, the polishing head PH presses the wafer W against the polishing surface 1a of the polishing pad 1. The polishing liquid supply nozzle 3 supplies the polishing liquid onto the polishing surface 1a, and the wafer W is polished by sliding contact with the polishing pad 1 in the presence of the polishing liquid.

[0114] The grinding device PA includes: a head shaft 16, which is connected to the grinding head PH; an up-and-down moving mechanism 5, which moves the grinding head PH up and down through the head shaft 16; a rotating mechanism 6, which rotates the grinding head PH through the head shaft 16; and a swing arm 14, which carries the up-and-down moving mechanism 5 and the rotating mechanism 6.

[0115] The vertical movement mechanism 5 and the rotating mechanism 6 are supported on the support platform 14a of the swing arm 14. The vertical movement mechanism 5 includes a vertical movement motor 30 and a connecting member 31 connecting the vertical movement motor 30 and the head shaft 16. The vertical movement motor 30 is, for example, a precision motor such as a servo motor. The vertical movement motor 30 is driven to move the head shaft 16 up and down via the connecting member 31. The polishing head PH moves up and down together with the head shaft 16.

[0116] The rotating mechanism 6 includes a rotating motor 22, a rotating cylinder 23 mounted on the head shaft 16 via a key (not shown), and a timing belt 24 stretched between the rotating motor 22 and the rotating cylinder 23. The rotating motor 22 is a precision motor such as a servo motor.

[0117] The rotating cylinder 23 is rotatably supported by bearings 25A and 25B, and the bearings 25A and 25B are mounted on the support platform 14a. The rotating motor 22 rotates the rotating cylinder 23 via the timing belt 24. The rotating cylinder 23 transmits its rotational force to the head shaft 16, rotating the head shaft 16. The grinding head PH rotates together with the head shaft 16.

[0118] The head shaft 16 is inserted into the rotating cylinder 23 so as to be movable up and down relative to the rotating cylinder 23. Therefore, the rotational force acting on the rotating cylinder 23 is transmitted to the head shaft 16, while the up and down movement force acting on the head shaft 16 is not transmitted to the rotating cylinder 23. A rotary joint 32 is mounted on the upper end of the head shaft 16.

[0119] The polishing device PA includes a swing mechanism 7 for swinging a swing arm 14. The swing mechanism 7 includes an arm shaft 12 for supporting the swing arm 14 and a swing motor 20 for swinging the swing arm 14 via the arm shaft 12. The swing motor 20 is, for example, a precision motor such as a servo motor. The swing motor 20 is driven to swing the swing arm 14 via the arm shaft 12. In this way, the swing arm 14 is configured to be able to rotate around the arm shaft 12.

[0120] The polishing device PA includes a plurality of fluid lines 33, 77, and 88 extending to the polishing head PH through a rotary joint 32. These plurality of fluid lines 33, 77, and 88 are connected to a pressure regulating device 36. The pressure regulating device 36 is configured to regulate the pressure of the fluid supplied to the polishing head PH through the plurality of fluid lines 33, 77, and 88. As an example of the supplied fluid, nitrogen gas and clean dry air can be cited.

[0121] The polishing apparatus PA includes a control device 10 that controls the operation of components of the polishing apparatus PA (e.g., the polishing table 2, the polishing head PH, the dresser 41, the polishing liquid supply nozzle 3, etc.). The control device 10 includes a storage unit 10a storing a program and a calculation unit 10b that performs calculations according to commands included in the program.

[0122] The storage unit 10a includes a main storage device such as a RAM and an auxiliary storage device such as a hard disk drive (HDD) and a solid state drive (SSD). Examples of the calculation unit 10b include a CPU (central processing unit) and a GPU (graphics processing unit).

[0123] The control device 10 is composed of at least one computer. The computer may also be one server or multiple servers. The control device 10 may be an edge server, a cloud server connected to a communication network such as the Internet or a local area network, or a fog computing device (gateway, fog server, router, etc.) provided in the network. The control device 10 may also be multiple servers connected via a communication network such as the Internet or a local area network. For example, the control device 10 may also be a combination of an edge server and a cloud server.

[0124] The control device 10 is electrically connected to the pressure regulating device 36. Therefore, the control device 10 is configured to regulate the pressure of the fluid supplied to the polishing head PH (particularly the elastic membrane 100) through the fluid lines 33, 77, and 88 by operating the pressure regulating device 36.

[0125] The polishing apparatus PA includes a film thickness sensor ES disposed below the polishing table 2. The film thickness sensor ES is configured to detect a film thickness signal that changes with the film thickness of the wafer W. An example of the film thickness sensor ES is an optical sensor or an eddy current sensor.

[0126] In one embodiment, the film thickness sensor ES may be embedded in the polishing table 2. The film thickness sensor ES is electrically connected to the control device 10, and is configured to send a film thickness signal detected by the film thickness sensor ES to the control device 10. The control device 10 measures the film thickness of the wafer W based on the film thickness signal, and ends the polishing of the wafer W based on the film thickness of the wafer W.

[0127] The polishing process of the wafer W is as follows. While the polishing table 2 and the polishing head PH are rotated, the polishing liquid is supplied from the polishing liquid supply nozzle 3 to the polishing surface 1a of the polishing pad 1. In a state where the polishing liquid is present on the polishing surface 1a, the polishing head PH presses the wafer W against the polishing surface 1a while rotating the wafer W. As a result, the surface of the wafer W is polished by the mechanical action of the abrasive grains contained in the polishing liquid and the chemical action of the polishing liquid.

[0128] During the polishing of the wafer W, the control device 10 obtains a film thickness signal detected by the film thickness sensor ES, and measures the film thickness of the wafer W based on the obtained polishing signal. The control device 10 controls the polishing operation of the wafer W based on the measured film thickness. When the film thickness of the wafer W reaches the target film thickness, the control device 10 operates the polishing head PH to end the polishing of the wafer W.

[0129] Generally, the elastic membrane has a plurality of partition walls for forming divided pressure chambers. Such an elastic membrane is difficult to expand and contract, especially near the partition walls, and may not be able to uniformly transmit the pressure in the pressure chamber to the wafer W. As a result, the polishing head PH cannot apply an appropriate pressing force to the wafer W, which may have an adverse effect on the uniformity of the wafer W. Therefore, in this embodiment, the elastic membrane 100 has a structure that can improve the expansion and contraction. The structure of the elastic membrane 100 is described below with reference to the accompanying drawings.

[0130] Figure 2 FIG. 2 is an enlarged cross-sectional view showing one embodiment of a grinding head. Figure 2 As shown, the polishing head PH includes: a head body 49; a holding ring mechanism 57 for preventing the wafer W from flying out; and an elastic membrane 100 for holding the wafer W and being arranged below the head body 49.

[0131] The head body 49 includes a circular flange 53 connected to the head shaft 16, a spacer 70 mounted on the lower surface of the flange 53, and a carrier (base plate) 71 mounted on the lower surface of the spacer 70. The carrier 71 is connected to the flange 53 via the spacer 70, and the flange 53, the spacer 70, and the carrier 71 rotate and move up and down as a whole.

[0132] The retaining ring mechanism 57 includes a retaining ring 75 surrounding the wafer W and a retaining ring pressing mechanism 56 disposed above the retaining ring 75. The retaining ring 75 is disposed so as to surround the peripheral edge of the wafer W and can come into contact with the polishing surface 1a of the polishing pad 1. The retaining ring 75 prevents the wafer W from flying out of the polishing head PH during polishing of the wafer W.

[0133] The retaining ring 75 is configured to be movable up and down independently of the flange portion 53 by the operation of the retaining ring pressing mechanism 56. The retaining ring pressing mechanism 56 includes an annular rolling diaphragm 76 and a fluid line 77 for supplying a fluid (for example, air) to the rolling diaphragm 76.

[0134] The rolling diaphragm 76 has a retaining ring pressure chamber SP formed therein. The fluid pipeline 77 passes through the flange portion 53 and communicates with the retaining ring pressure chamber SP. Therefore, when the fluid is supplied to the retaining ring pressure chamber SP through the fluid pipeline 77, the rolling diaphragm 76 presses down the retaining ring 75. The retaining ring 75 is pressed against the polishing surface 1a of the polishing pad 1 by the downward pressure.

[0135] On the other hand, a vacuum is formed in the retaining ring pressure chamber SP through the fluid line 77, whereby the rolling diaphragm 76 raises the retaining ring 75. The retaining ring pressure chamber SP is also connected to an atmosphere opening mechanism (not shown), so that the retaining ring pressure chamber SP can also be opened to the atmosphere.

[0136] Figure 3 It is a top view showing one embodiment of the elastic membrane. Figure 4 yes Figure 3 Local cross-sectional view at line AA. Figure 5 yes Figure 3 The elastic membrane 100 is made of a soft rubber material having excellent strength and durability, such as EPDM, polyurethane rubber, or silicone rubber.

[0137] The elastic membrane 100 includes a flat pressing portion 101 for pressing the wafer W, a plurality of partition walls 102 extending from the pressing portion 101 toward the head body 49, and a peripheral wall 103 connected to the outermost partition wall 102 of the plurality of partition walls 102 and constituting the outer shape of the elastic membrane 100. The pressing portion 101, the partition walls 102, and the peripheral wall 103 are integrally formed components.

[0138] The elastic membrane 100 has: a pressure chamber A1, which is formed in the center of the elastic membrane 100 by a pressing portion 101, a plurality of partition walls 102 and a peripheral wall 103; and a plurality of pressure chambers A2 to A5, which are divided along the radial direction and the circumferential direction of the wafer W (i.e., the polishing head PH).

[0139] The pressure chamber A1 is arranged along the central axis CL2 of the head shaft 16. Figure 3 In the illustrated embodiment, the pressure chamber A1 has a circular shape when viewed from the head shaft 16 side (ie, from above). In one embodiment, the pressure chamber A1 may also have a polygonal shape.

[0140] Figure 6 2 is a diagram showing another embodiment of the elastic membrane. Figure 6 As shown, the pressure chamber A1 may include a plurality of pressure chambers A1-A, A1-B, A1-C, and A1-D having a fan-shaped shape when viewed from above. The plurality of pressure chambers A1-A to A1-D are arranged at equal intervals along the circumferential direction of the elastic membrane 100.

[0141] like Figure 6 (as well as Figure 3 ), the pressure chambers A2 to A5 are arranged around the pressure chamber A1 and are arranged at equal intervals along the circumferential direction of the elastic membrane 100. More specifically, the pressure chamber A2 is composed of a plurality of pressure chambers A2-A, A2-B, A2-C, and A2-D surrounding the pressure chamber A1. The pressure chamber A3 is composed of a plurality of pressure chambers A3-A, A3-B, A3-C, and A3-D surrounding the pressure chamber A2.

[0142] Similarly, pressure chamber A4 is composed of a plurality of pressure chambers A4-A, A4-B, A4-C, and A4-D surrounding pressure chamber A3. Pressure chamber A5 is composed of a plurality of pressure chambers A5-A, A5-B, A5-C, and A5-D surrounding pressure chamber A4.

[0143] Figure 7 FIG. 2 is a diagram showing another embodiment of the elastic membrane. Figure 6 In the embodiment shown, the plurality of pressure chambers A2 to A5 constituting the pressure chamber A1 are arranged linearly (i.e., on a straight line) along the radial direction of the elastic membrane 100. Figure 7 As shown in FIG. 1 , the plurality of pressure chambers A2 to A5 arranged along the radial direction of the elastic membrane 100 may be arranged at a predetermined rotation angle (in Figure 7 In the embodiment shown, the arrangement is staggered at a rotation angle of 45 degrees.

[0144] The fluid line 33 passes through the head body 49 (more specifically, the flange 53, the spacer 70, and the carrier 71) and communicates with the pressure chambers A1 to A5, respectively (see Figure 2 ). Therefore, the control device 10 can individually control the pressure of the fluid supplied to the pressure chambers A1 to A5 through the fluid line 33 by operating the pressure regulating device 36.

[0145] The pressure chambers A1 to A5 are connected to vacuum lines (not shown). The control device 10 is configured to control the operation of a vacuum pump (not shown) connected to the vacuum line. Therefore, the control device 10 can form a vacuum in each of the pressure chambers A1 to A5 by operating the vacuum pump.

[0146] The pressure chambers A1 to A5 are also connected to atmosphere opening mechanisms (not shown), respectively. Therefore, the pressure chambers A1 to A5 can also be opened to the atmosphere.

[0147] The plurality of partition walls 102 have substantially the same structure, and therefore, in the following, reference is made to Figure 5 The structure of a single partition wall 102 will be described.

[0148] like Figure 5 As shown, the partition wall 102 has a bulging structure that bulges in a direction away from the pressed part 101. The partition wall 102 having such a bulging structure forms a pressurizing chamber MSP for applying a pressing force to the pressed part 101.

[0149] The pressurized chamber MSP is formed between the pressure chambers A1 to A5 that are adjacent to each other along the radial direction of the elastic membrane 100. More specifically, the plurality of pressurized chambers MSP are arranged between the pressure chambers A1 and A2, between the pressure chambers A2 and A3, between the pressure chambers A3 and A4, and between the pressure chambers A4 and A5. The pressurized chamber MSP arranged at the outermost side of the elastic membrane 100 is adjacent to the pressurized chamber MSP arranged between the pressure chambers A4 and A5.

[0150] In this way, mutually adjacent pressure chambers among the pressure chambers A1 to A5 are arranged on both sides of the pressurizing chamber MSP. The pressurizing chamber MSP is formed above the pressing part 101, that is, above the pressure chambers A1 to A5.

[0151] The polishing device PA is provided with a fluid line 88 extending to the pressurizing chamber MSP through the rotary joint 32 (see Figure 2 ). The fluid line 88 is connected to the pressure regulating device 36. Therefore, the control device 10 can independently control the pressure of the fluid supplied to the pressurizing chamber MSP through the fluid line 88 by operating the pressure regulating device 36.

[0152] The pressurized chamber MSP is connected to a vacuum line (not shown). The control device 10 is configured to control the operation of a vacuum pump (not shown) connected to the vacuum line. Therefore, the control device 10 can form a vacuum in the pressurized chamber MSP. The pressurized chamber MSP is also connected to an atmosphere opening mechanism (not shown). Therefore, the pressurized chamber MSP can also be opened to the atmosphere.

[0153] Figure 8 (a) is a diagram showing an example of a partition wall mounted on a partition wall holder, Figure 8 (b) is a diagram showing another example of a partition wall mounted on a partition wall retainer, Figure 8 (c) is a diagram showing a state in which the partition wall attached to the partition wall holder is inclined.

[0154] like Figure 8 (a)(and Figure 2 ), the carrier 71 is provided with a number of partition wall holders 110 corresponding to the number of partition walls 102. The partition wall holder 110 is fixed to the lower surface of the carrier 71 and has a flow hole 110a connected to the fluid pipeline 88 (and the vacuum pipeline). Therefore, the pressurized chamber MSP is connected to the fluid pipeline 88 through the flow hole 110a of the partition wall holder 110.

[0155] The partition wall 102 has a first wall portion 120A and a second wall portion 120B forming a bulge structure. The first wall portions 120A and 120B are adjacent to each other and are symmetrically arranged. The first wall portions 120A and 120B have basically the same structure, so in the following, the first wall portions 120A and 120B are sometimes not particularly distinguished and are referred to as the wall portion 120.

[0156] The wall portion 120 includes a base end portion 125 connected to the pressing portion 101, a wide portion 130 connected to the base end portion 125 and arranged to be separated from (adjacent to) the pressing portion 101, and a clamping portion 131 connected to the wide portion 130 and held by the partition wall holder 110. The base end portion 125, the wide portion 130, and the clamping portion 131 are integrally formed.

[0157] The first wall portions 120A and 120B respectively have a base end portion 125, a wide portion 130, and a clamping portion 131. The base end portions 125 adjacent to each other are connected to each other at the pressing portion 101. These base end portions 125 extend in directions away from each other from the pressing portion 101 and have a V-shaped cross-sectional shape. In other words, the first wall portions 120A and 120B have a V-shaped cross-sectional shape approaching each other toward the pressing portion 101 and are connected to each other at the pressing portion 101.

[0158] The adjacent wide portions 130 have a wide shape that is separated from each other. The partition wall holder 110 is sandwiched between these wide portions 130. The adjacent clamping portions 131 are close to each other so as to cover the partition wall holder 110 and are fixed to the upper end of the partition wall holder 110.

[0159] More specifically, the clamping portion 131 has a protrusion 131a protruding toward the pressing portion 101. The partition wall holder 110 has a fitting portion 110b having a shape corresponding to the protrusion 131a. The fitting portion 110b is formed at the upper end of the partition wall holder 110.

[0160] By attaching the protrusion 131a to the fitting portion 110b, the partition wall 102 is firmly held in its entirety by the partition wall holder 110. Figure 8 In the embodiment shown in (a), the partition wall holder 110 is entirely disposed in the pressurized chamber MSP, but in one embodiment, at least a portion of the partition wall holder 110 may also be disposed in the pressurized chamber MSP. In this case, the fitting portion 110b does not necessarily have to be formed at the upper end of the partition wall holder 110.

[0161] When the partition wall 102 is attached to the partition wall holder 110, the flow hole 110a of the partition wall holder 110 communicates with the pressurized chamber MSP of the partition wall 102. In this state, fluid is supplied to the pressurized chamber MSP through the fluid line 88, whereby the partition wall 102 as a whole elastically deforms (expands).

[0162] According to the present embodiment, the partition wall 102 having the bulging structure is configured to apply a pressing force to the pressing portion 101 by elastic deformation thereof (see Figure 5 Therefore, the elastic film 100 can improve its elasticity, especially the elasticity of the pressing part 101.

[0163] Patent document 1 discloses a flexible diaphragm having an air pressure introduction portion. The flexible diaphragm is supported by a partition wall support portion that supports its partition wall, and the partition wall support portion is formed by a part of a support member that is a component of the polishing head. Thus, in Patent document 1, the auxiliary air pressure area is formed by the flexible diaphragm and the partition wall support portion of the support member.

[0164] On the other hand, in the present embodiment, the pressurizing chamber MSP is formed of the partition wall 102 having a bulging structure. Therefore, the partition wall 102 as a whole can be elastically deformed to a large extent by supplying the fluid to the pressurizing chamber MSP, and a pressing force can be applied to the pressing part 101 more actively.

[0165] Thus, the partition wall 102 having the bulging structure can greatly contribute to the improvement of the stretchability of the pressing portion 101. Patent Document 1 does not disclose a flexible membrane having such a structure, and the flexible membrane of Patent Document 1 has a structure different from that of the elastic membrane 100 according to the present embodiment.

[0166] In the present embodiment, the partition wall 102 includes the wide portion 130 and the clamping portion 131, all of which are made of elastic components. Therefore, the polishing head PH can be assembled by a simple method of simply mounting the partition wall 102 on the partition wall holder 110 in a manner covering the partition wall holder 110. Furthermore, by configuring the wide portion 130 to be elastically deformable, even if the elastic film 100 has some assembly error, the elastic film 100 can absorb the assembly error.

[0167] Moreover, in the present embodiment, the polishing head PH has a structure in which the partition wall holder 110 is sandwiched by the elastic film 100. With such a structure, the polishing head PH can improve the sealing performance of the pressurized chamber MSP and prevent the intrusion of liquid into the pressurized chamber MSP. In the present embodiment, the elastic film 100 has a wide width portion 130 that can be elastically deformed. Therefore, the elastic film 100 can improve the assembly performance and sealing performance of the polishing head PH.

[0168] When the partition wall 102 is made of a hard material or the distance between the elastic membrane 100 and the wafer W (i.e., the membrane height) is large, even if the fluid is supplied to the pressurization chamber MSP, the partition wall 102 may not be able to sufficiently increase the stretchability of the pressing portion 101. In the present embodiment, the elastic membrane 100 has the partition wall 102 that can be elastically deformed, so the partition wall 102 can be greatly expanded and contracted.

[0169] The purpose of the elastic film 100 is to improve the uniformity of the wafer W by compensating for the pressure loss applied to the wafer W from the pressing portion 101. According to the present embodiment, the elastic film 100 having the partition wall 102 can sufficiently compensate for the pressure loss applied to the wafer W.

[0170] When the elastic film 100 has a high rubber hardness, the elastic film 100 does not expand or contract sufficiently, which may adversely affect the uniformity of the wafer W. Therefore, it is necessary to change the thickness and shape of the elastic film 100 to adjust the rubber hardness of the elastic film 100. However, in this case, a plurality of molds for manufacturing elastic films 100 having various shapes must be prepared, which costs a lot of money and takes a lot of time, and is not realistic.

[0171] Therefore, if Figure 8 (b) and Figure 8 As shown in (c) of FIG. 8 , the polishing head PH may include a width direction gap G formed between the wall portion 120 and the partition wall holder 110 . The width direction gap G is formed between the wide width portion 130 and the partition wall holder 110 .

[0172] By forming the width direction gap G, the wall portion 120 is not blocked by the partition wall holder 110 and can be deformed more elastically (see Figure 8 (c)). Therefore, there is no need to change the thickness and shape of the elastic film 100, and the cost required for manufacturing the elastic film 100 can be reduced.

[0173] Fig. 9 2 is a diagram showing another embodiment of the partition wall. Fig. 9 As shown, the partition wall 102 has a third wall portion 120C connected to the first wall portions 120A and 120B. The third wall portion 120C extends toward the pressing part 101 from the connection portion between the first wall portions 120A and 120B.

[0174] The third wall 120C extends perpendicularly to the pressing part 101. The third wall 120C has one end connected to the pressing part 101 and the other end connected to the base ends 125, 125 of the first walls 120A, 120B. With such a structure, the partition wall 102 has a Y-shaped cross section.

[0175] In one embodiment, the elastic film 100 may also include a plurality of partition walls 102, wherein the plurality of partition walls 102 include a partition wall 102 having a V-shaped cross-sectional shape (see Figures 1 to 8 ) and a partition wall 102 having a Y-shaped cross-sectional shape (refer to Fig. 9 ).

[0176] Fig.10 (a) is a diagram showing an embodiment of the peripheral wall of the elastic membrane, Fig.10 (b) is a diagram showing another embodiment of the peripheral wall. Fig.10 As shown in (a) of FIG. 5 , the partition wall 102 constituting the pressurized chamber MSP formed on the upper part of the pressure chamber A5 is arranged adjacent to the peripheral wall 103 and has a wall portion 120 connected to the peripheral wall 103. Hereinafter, the wall portion 120 connected to the peripheral wall 103 is sometimes referred to as a peripheral wall side wall portion 120. The partition wall 102 having the peripheral wall side wall portion 120 is sometimes referred to as a peripheral wall side partition wall 102.

[0177] like Fig.10 As shown in (a), the peripheral wall side wall portion 120 has a base end portion 125 connected to the peripheral wall 103, and a wide portion 130 and a clamping portion 131 connected to the base end portion 125. The base end portion 125 extends parallel to the pressing portion 101. By supplying fluid to the pressurization chamber MSP formed by the partition wall 102 having a bulging structure and the peripheral wall 103, the peripheral wall side partition wall 102 applies a pressing force to the pressing portion 101 via the peripheral wall 103.

[0178] like Fig.10 As shown in (b), the base end portion 125 of the peripheral wall side wall portion 120 may also extend obliquely relative to the pressing portion 101. More specifically, the base end portion 125 extends obliquely downward toward the pressing portion 101 and is connected to the connecting portion (or the pressing portion 101) between the pressing portion 101 and the peripheral wall 103. With such a structure, the peripheral wall side partition wall 102 can apply a pressing force to the pressing portion 101 by supplying a fluid to the pressurization chamber MSP.

[0179] Fig.11 (a) and Fig.11 (b) is a diagram showing the action of the polishing head adsorbing and holding the wafer. First, fluid is supplied to the pressurizing chamber MSP so that the entire pressing portion 101 is in close contact with the wafer W (see Fig.11 In this state, a vacuum is formed in each pressure chamber A1 to A5, thereby forming an adsorption space V on the lower surface of the pressing part 101 (see Fig.11 (b)). The adsorption space V corresponds to the suction cup formed by the pressing portion 101.

[0180] Thus, the polishing head PH can adsorb and hold the wafer W by forming the adsorption space V on the lower surface of the pressing portion 101 (adsorption process). In this state, the polishing head PH is transported to a predetermined polishing position (i.e., above the polishing pad 1) to start polishing the wafer W.

[0181] When polishing of the wafer W starts, the polishing head PH presses the wafer W against the polishing pad 1 by supplying fluid to the pressure chambers A1 to A5 , and applies a pressing force to the pressing portion 101 through the partition wall 102 by supplying fluid to the pressurizing chamber MSP.

[0182] Basically, the pressure of the fluid supplied to the pressurizing chamber MSP is arbitrarily determined. In one embodiment, in order to achieve the purpose of improving the elasticity of the pressing part 101, the pressure of the fluid supplied to the pressurizing chamber MSP may be determined to be the lowest pressure among the pressure chambers A1 to A5.

[0183] In one embodiment, in order to apply a pressing force to the pressing portion 101 directly below the partition wall 102 constituting the pressurizing chamber MSP, the pressure of the fluid supplied to the pressurizing chamber MSP may be determined to be higher than the pressure of the fluid supplied to the pressure chambers A1 to A5.

[0184] Fig.12 2 is a diagram showing another embodiment of the elastic membrane. Fig.12 As shown, the elastic film 100 may also have a suction hole H formed at the pressing portion 101. Fig.12 In the illustrated embodiment, the suction hole H is formed in the pressing portion 101 forming the pressure chamber A1.

[0185] When the wafer W is brought into close contact with the pressing portion 101, a vacuum is formed in the pressure chamber A1, whereby the wafer W is adsorbed to the pressing portion 101 through the suction holes H. In this way, the polishing head PH can adsorb and hold the wafer W through the suction holes H while forming the adsorption space V. By forming the suction holes H, moisture existing between the wafer W and the pressing portion 101 can be removed through the suction holes H.

[0186] After polishing of the wafer W is completed, the polishing head PH transfers the wafer W to a predetermined next process position while adsorbing and holding the wafer W by performing the above-mentioned adsorption step. The polishing head PH is configured to detach the wafer W transferred to the next process position.

[0187] Fig.13 FIG. 2 is a diagram showing the action of the polishing head to release the wafer. Fig.13 As shown, the control device 10 is configured to detach the wafer W from the elastic film 100 by forming a vacuum in the pressurizing chamber MSP and supplying a fluid to the pressure chambers A1 to A5 (detachment step).

[0188] Through the above-mentioned separation process, the pressing part 101 directly below the partition wall 102 constituting the pressurized chamber MSP approaches the carrier 71, while the pressing part 101 constituting each of the pressure chambers A1 to A5 expands downward. In this way, the polishing head PH exposes the gap between the pressing part 101 and the wafer W.

[0189] like Fig.13 As shown, the polishing apparatus PA includes a release nozzle RN that sprays a fluid toward the gap between the pressing portion 101 and the wafer W. As an example of the fluid sprayed from the release nozzle RN, pure water (DIW) and nitrogen gas can be cited. After the wafer W is detached from the polishing head PH, when the fluid is sprayed from the release nozzle RN toward the gap between the pressing portion 101 and the wafer W, the wafer W is reliably detached from the polishing head PH.

[0190] The above-mentioned embodiments are recorded for the purpose of enabling persons with common knowledge in the technical field to which the present invention belongs to implement the present invention. Various modifications of the above-mentioned embodiments can certainly be made by those skilled in the art, and the technical idea of ​​the present invention can also be applied to other embodiments. Therefore, the present invention is not limited to the described embodiments, but is interpreted as the widest scope of the technical idea defined by the scope of the patent claim.

Claims

1. An elastic film, which can be applied to a polishing head for polishing a substrate, characterized in that: The elastic membrane has: A pressing portion that presses the substrate; and The partition wall has a bulging structure, and the bulging structure forms a pressurizing chamber for applying a pressing force to the pressing part.

2. The elastic membrane according to claim 1, characterized in that The partition wall has a first wall portion and a second wall portion forming the bulging structure. The first wall portion and the second wall portion have: wide width portions, the wide width portions being separated from each other; and The clamping portion is connected to the wide portion and is close to each other.

3. The elastic membrane according to claim 1, characterized in that: The partition wall includes a first wall portion and a second wall portion, the first wall portion and the second wall portion having a V-shaped cross-sectional shape approaching each other toward the pressing portion, The first wall portion and the second wall portion are connected to each other in the pressing portion.

4. The elastic membrane according to claim 1, characterized in that The partition wall includes a first wall portion, a second wall portion, and a third wall portion, wherein the first wall portion, the second wall portion, and the third wall portion have a Y-shaped cross-sectional shape. The third wall portion is connected to the first wall portion and the second wall portion, and extends from a connection portion with the first wall portion and the second wall portion toward the pressing portion.

5. The elastic membrane according to claim 1, characterized in that: The partition wall has a first pressure chamber and a second pressure chamber disposed on both sides of the pressurized chamber. The pressurizing chamber is disposed above the first pressure chamber and the second pressure chamber.

6. The elastic membrane according to claim 1, characterized in that The elastic membrane has a peripheral wall constituting the outer shape of the elastic membrane, The partition wall has a peripheral wall side wall portion that is disposed adjacent to the peripheral wall and extends obliquely with respect to the pressing portion.

7. A grinding head, characterized in that: have: The elastic film according to any one of claims 1 to 6; and A head body holds the elastic membrane.

8. The grinding head according to claim 7, characterized in that: The head body includes a partition wall holder for holding the partition wall. At least a portion of the partition wall holder is disposed in the pressurizing chamber.

9. The grinding head according to claim 8, characterized in that: The polishing head has a widthwise gap formed between the partition wall and the partition wall holder.

10. A grinding method, characterized in that: holding the substrate by an elastic film pressing the substrate, The substrate is pressed against the polishing pad by supplying a fluid to a pressure chamber formed by a pressing portion that presses the substrate while the substrate is held. A fluid is supplied to a pressurizing chamber formed by the partition wall having the bulge structure to apply a pressing force to the pressing portion.

11. The grinding method according to claim 10, characterized in that: The step of holding the substrate includes supplying a fluid to the pressurizing chamber and forming a vacuum in the pressurizing chamber, thereby forming a suction space on a lower surface of the pressing portion to suction the substrate.

12. The grinding method according to claim 10, characterized in that: The polishing method includes the steps of forming a vacuum in the pressure chamber and supplying a fluid to the pressure chamber after polishing of the substrate is completed, thereby detaching the substrate from the elastic film.

13. The grinding method according to claim 10, characterized in that: The partition wall has a first wall portion and a second wall portion forming the bulging structure. The first wall portion and the second wall portion have: wide width portions, the wide width portions being separated from each other; and The clamping portion is connected to the wide portion and is close to each other.

14. The grinding method according to claim 10, characterized in that: The partition wall includes a first wall portion and a second wall portion, the first wall portion and the second wall portion having a V-shaped cross-sectional shape approaching each other toward the pressing portion, The first wall portion and the second wall portion are connected to each other at the pressing portion.

15. The grinding method according to claim 10, characterized in that: The partition wall includes a first wall portion, a second wall portion, and a third wall portion, wherein the first wall portion, the second wall portion, and the third wall portion have a Y-shaped cross-sectional shape. The third wall portion is connected to the first wall portion and the second wall portion, and extends from a connection portion with the first wall portion and the second wall portion toward the pressing portion.

16. The grinding method according to claim 10, characterized in that: The elastic membrane has a peripheral wall constituting the outer shape of the elastic membrane, The partition wall has a peripheral wall side wall portion that is disposed adjacent to the peripheral wall and extends obliquely with respect to the pressing portion.

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