Top ring and substrate processing apparatus

Abstract

Provided is a top ring capable of improving the uniformity of polishing. A top ring for holding a substrate is provided with: a base member connected to a rotating shaft; a substrate adsorption member including a porous member having a substrate adsorption surface for adsorbing the substrate and a pressure reducing portion communicating with the pressure reducing means; and a first pressing means disposed between the base member and the substrate suction member and having a plurality of first pressing means disposed on a side of the substrate suction member opposite to the substrate suction surface, the first pressing means are configured so as to be capable of applying a pressing force to the substrate adsorption member independently of each other.

Description

Technical Field

[0001] The present application relates to a top ring and a substrate processing device. Background Art

[0002] In order to flatten the surface of the substrate, a chemical mechanical polishing (CMP) device is used in the manufacture of semiconductor components. The substrates used in the manufacture of semiconductor components are mostly disc-shaped. In addition, not limited to semiconductor components, the flatness requirements when flattening the surface of quadrilateral (square) substrates such as copper clad layer substrates (CCL, copper clad laminate) or printed circuit boards (PCB, printed circuit boards), mask substrates, display panels, etc. are also increased. In addition, the requirements for flattening the surface of packaging substrates equipped with electronic components such as PCB substrates are also increased.

[0003] A substrate processing apparatus such as a chemical mechanical polishing apparatus includes, for example, a top ring for holding a substrate. The top ring holds a substrate WF by vacuum suction through a substrate suction member, and in this state, the top ring is rotated while being pressed against a polishing pad on a polishing table that rotates in the same manner, thereby chemically mechanically polishing the substrate WF.

[0004] In order to adjust the pressing force (pressing force) of the substrate on the polishing pad by the top ring, a plurality of piezoelectric elements are arranged on the top ring (Japanese Patent Application Publication No. 9-225820 (Patent Document 1) and Japanese Patent Application Publication No. 2000-094301 (Patent Document 2)).

[0005] Prior art literature

[0006] Patent Literature

[0007] Patent Document 1: Japanese Patent Application Laid-Open No. 9-225820

[0008] Patent Document 2: Japanese Patent Application Publication No. 2000-094301

[0009] Problems to be solved by the invention

[0010] In the above-mentioned polishing apparatus, uneven polishing may occur on the polished surface of the substrate due to uneven thickness of the substrate and the in-plane uniformity of the porous member / shielding member constituting the substrate adsorption portion of the top ring. For example, in order to obtain flatness (uniformity of thickness) for porous members, plane processing (milling processing) using a plane milling cutter is performed, but the processing marks may be transferred to the polishing rate as they are.

[0011] In the case of plane cutting processing based on milling, it is difficult to process the flatness and / or thickness accuracy of the substrate adsorption surface of the porous component to a level that does not affect the grinding performance with high precision. In order to pursue a level that does not affect, it is necessary to select a higher precision processing method, which leads to increased costs. In addition, the square substrate has a tendency to have a large degree of uneven thickness, which is different from semiconductor wafers in its characteristics, and there is also a concern that the uneven thickness will greatly affect grinding.

[0012] In order to improve the in-plane uniformity of the polishing rate, the top ring is sometimes provided with a plurality of pressurized chambers separated by an elastic membrane. By giving a difference in the pressure of each pressurized chamber, the uniformity of the force pressing the substrate can be corrected to a certain extent, but it is not possible to give a small and complex pressure difference, and even if it is possible, it will become an expensive structure. Moreover, once the design is determined, it requires a lot of labor to change it. Moreover, even in the top ring with multiple piezoelectric elements (Japanese Patent Publication No. 9-225820 (Patent Document 1) and Japanese Patent Publication No. 2000-094301 (Patent Document 2)), there is still room for improvement from the perspective of improving the in-plane uniformity of the polishing rate. Summary of the invention

[0013] One object of the present application is to realize a top ring that can improve grinding uniformity.

[0014] According to one embodiment, a top ring for holding a substrate is disclosed, comprising: a base component connected to a rotating shaft; a substrate adsorption component, the substrate adsorption component including a porous component, the porous component having a substrate adsorption surface for adsorbing the substrate and a decompression portion connected to a decompression means; and a first pressurizing component, the first pressurizing component is arranged between the base component and the substrate adsorption component, and has a plurality of first pressurizing means arranged on a side of the substrate adsorption component opposite to the substrate adsorption surface, each of the first pressurizing means being configured to be able to apply a pressing force to the substrate adsorption component completely independently of each other. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a plan view showing the overall structure of a substrate processing apparatus according to one embodiment.

[0016] Figure 2 This is a perspective view schematically showing the structure of a polishing unit according to one embodiment.

[0017] Figure 3 This is a cross-sectional view schematically showing a top ring according to one embodiment.

[0018] Figure 4 This is a cross-sectional view schematically showing a top ring according to one embodiment.

[0019] Figure 5 yes Figure 3KK section.

[0020] Figure 6 yes Figure 3 mm section.

[0021] Figure 7 This is a modified example of the frame member of the substrate adsorption member.

[0022] Figure 8 This is an explanatory diagram for explaining an example of a method for calibrating a top ring.

[0023] Fig. 9 This is an explanatory diagram for explaining another example of the top ring correction method.

[0024] Fig.10 is a flowchart showing the calibration. DETAILED DESCRIPTION

[0025] The following and attached Figure 1 The following describes the embodiments of the top ring and substrate processing apparatus of the present invention. In the drawings, the same or similar elements are given the same or similar reference symbols, and the repeated description of the same or similar elements in the description of each embodiment is sometimes omitted. In addition, the features shown in each embodiment can also be applied to other embodiments as long as they do not contradict each other.

[0026] Figure 1 It is a plan view showing the overall structure of a substrate processing apparatus 1000 according to one embodiment. Figure 1 The substrate processing apparatus 1000 shown has a loading unit 100, a conveying unit 200, a grinding unit 300, a drying unit 500 and an unloading unit 600. In the illustrated embodiment, the conveying unit 200 has two conveying units 200A and 200B, and the grinding unit 300 has two grinding units 300A and 300B. In one embodiment, these units can be formed independently. By forming these units independently and combining the number of each unit arbitrarily, a substrate processing apparatus 1000 with different structures can be easily formed. In addition, the substrate processing apparatus 1000 is provided with a control device 900, and each component of the substrate processing apparatus 1000 is controlled by the control device 900. In one embodiment, the control device 900 can be composed of a general computer having an input and output device, a computing device 900a, a storage device 900b, etc. The computing device 900a may include a CPU (central processing unit), an MPU (microprocessor), etc. The storage device 900b may include any non-volatile memory and / or volatile memory.

[0027] <Loading Unit>

[0028] The loading unit 100 is a unit for introducing the substrate WF before polishing and cleaning into the substrate processing apparatus 1000. In one embodiment, the loading unit 100 is configured in accordance with the mechanical device interface standard (IPC-SMEMA-9851) of the Surface Mount Equipment Manufacturers Association (SMEMA).

[0029] In the illustrated embodiment, the transport mechanism of the loading unit 100 includes a plurality of transport rollers 202 and a plurality of roller shafts 204 to which the transport rollers 202 are attached. Figure 1 In the illustrated embodiment, three conveying rollers 202 are mounted on each roller shaft 204. The substrate WF is arranged on the conveying rollers 202, and the substrate WF is conveyed by the rotation of the conveying rollers 202. The position of the conveying rollers 202 mounted on the roller shaft 204 may be any position as long as it is a position that can stably convey the substrate WF. However, since the conveying rollers 202 contact the substrate WF, they should be arranged in an area where there is no problem even if the conveying rollers 202 contact the substrate WF to be processed. In one embodiment, the conveying rollers 202 of the loading unit 100 may be composed of a conductive polymer. In one embodiment, the conveying rollers 202 are electrically grounded via the roller shaft 204, etc. This is to prevent the substrate WF from being charged and damaging the substrate WF. Furthermore, in one embodiment, an ionizer (not shown) for preventing the substrate WF from being charged may also be provided in the loading unit 100.

[0030] <Transportation Unit>

[0031] Figure 1 The substrate processing apparatus 1000 shown in the figure includes two transport units 200A and 200B. The two transport units 200A and 200B may have the same structure, and therefore will be described together as the transport unit 200 below.

[0032] The transport unit 200 shown in the figure has 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 can be formed of a conductive polymer or a non-conductive polymer. The transport rollers 202 are driven by a motor not shown in the figure. The substrate WF is transported to the substrate delivery position by the transport rollers 202.

[0033] In one embodiment, the transport unit 200 includes 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 transported by the transport rollers 202 .

[0034] <Grinding Unit>

[0035] Figure 2 This is a perspective view schematically showing the structure of a polishing unit 300 according to one embodiment. Figure 1 The substrate processing apparatus 1000 shown in the figure includes two polishing units 300A and 300B. Since the two polishing units 300A and 300B can have the same structure, they are collectively described as the polishing unit 300 below.

[0036] like Figure 2 As shown, the polishing unit 300 includes: a polishing table 350; and a top ring 302, which constitutes a polishing head that holds a substrate as a polishing object and presses (presses) it against the polishing surface on the polishing table 350. The polishing table 350 is connected to a polishing table rotation motor (not shown) arranged below it via a table shaft 351, so that it can rotate 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 the polishing surface of the polishing substrate. In one embodiment, the polishing pad 352 can also be attached via a layer for facilitating peeling from the polishing table 350. Such a layer includes, for example, a silicone layer, a fluorine resin layer, etc., and for example, a structure described in Japanese Patent Publication No. 2014-176950 can also be used. All disclosed contents including the specification, patent scope, drawings and abstract of Japanese Patent Publication No. 2014-176950 are incorporated into this application as a whole by reference.

[0037] A polishing liquid supply nozzle 354 is provided above the polishing table 350, and the polishing liquid is supplied to the polishing pad 352 on the polishing table 350 through the polishing liquid supply nozzle 354. Figure 2 As shown, a passage 353 for supplying a polishing liquid is provided on the grinding table 350 and the table shaft 351. The passage 353 is connected to an opening 355 on the surface of the grinding table 350. A through hole 357 is formed in the grinding pad 352 at a position corresponding to the opening 355 of the grinding table 350, and the grinding liquid passing through the passage 353 is supplied from the opening 355 of the grinding table 350 and the through hole 357 of the grinding pad 352 to the surface of the grinding pad 352. In addition, the opening 355 of the grinding table 350 and the through hole 357 of the grinding pad 352 may be one or more. In addition, the positions of the opening 355 of the grinding table 350 and the through hole 357 of the grinding pad 352 may be arbitrary, and in one embodiment, they are arranged near the center of the grinding table 350.

[0038] Figure 2 Although not shown, in one embodiment, the polishing unit 300 includes a sprayer 358 (see FIG. 1 ) for spraying a liquid or a mixed fluid of a liquid and a gas toward the polishing pad 352. Figure 1 ). The liquid sprayed from the sprayer 358 is, for example, pure water, and the gas is, for example, nitrogen.

[0039] The top ring 302 (more specifically, the base member 420 described later) is connected to the top ring shaft 18, and the top ring shaft 18 is moved up and down relative to the swing arm 360 by the up and down movement mechanism 319. By the up and down movement of the top ring shaft 18, the top ring 302 as a whole can be moved up and down relative to the swing arm 360 to be positioned. The top ring shaft 18 is driven to rotate by a top ring rotation motor (not shown). By the rotation of the top ring shaft 18, the top ring 302 is rotated around the top ring shaft 18.

[0040] The top ring 302 can hold a quadrilateral substrate WF on its lower surface. The substrate WF can be a CCL substrate, a PCB substrate, a mask substrate, a display panel, or any other quadrilateral substrate. A plurality of wiring units are formed on a certain substrate, and each of the plurality of wiring units has a wiring pattern. In addition, the plurality of wiring units of the substrate after the grinding process are sometimes respectively packaged with bare crystals of IC chips, etc. The swing arm 360 is configured to be able to rotate around the support shaft 362. The top ring 302 can move between the substrate handover position of the above-mentioned conveying unit 200 and the top of the grinding 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 WF against the surface (grinding surface) 352a of the grinding pad 352. At this time, the top ring 302 and the polishing table 350 are rotated respectively, and the polishing liquid is supplied to the polishing pad 352 from the polishing liquid supply nozzle 354 provided above the polishing table 350 and / or from the opening 355 provided on the polishing table 350. In this way, the substrate WF can be pressed against the polishing surface 352a of the polishing pad 352 to polish the surface of the substrate WF. During the polishing of the substrate WF, the swing arm 360 can also be fixed or swung so that the top ring 302 passes through the center of the polishing pad 352 (covering the through hole 357 of the polishing pad 352).

[0041] The vertical movement mechanism 319 for vertically moving the top ring shaft 18 and the top ring 302 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 platform 29 supported by a support column 130; and an AC servo motor 38 provided on the support platform 29. The support platform 29 that supports the servo motor 38 is fixed to the swing arm 360 via the support column 130.

[0042] The ball screw 32 includes a screw shaft 32a connected to the servo motor 38 and a nut 32b on which the screw shaft 32a is screwed. The top ring shaft 18 and the bridge 28 are integrally movable up and down. Therefore, when the servo motor 38 is driven, the bridge 28 moves up and down via the ball screw 32, thereby the top ring shaft 18 and the top ring 302 move up and down.

[0043] The polishing unit 300 of one embodiment includes a dressing unit 356 for dressing the polishing surface 352a of the polishing pad 352. The dressing unit 356 includes a dresser 50 that is in sliding contact with the polishing surface 352a; a dresser shaft 51 that is connected to the dresser 50; a cylinder 53 that is provided at the upper end of the dresser shaft 51; and a swing arm 55 that supports the dresser shaft 51 so that it can rotate freely. The lower part of the dresser 50 is composed of a dressing component 50a, and needle-shaped diamond particles are attached to the lower surface of the dressing component 50a. The cylinder 53 is arranged on a support table 57 supported by pillars 56, and these pillars 56 are fixed to the swing arm 55.

[0044] The swing arm 55 is driven by a motor not shown in the figure, and is configured to rotate around the support shaft 58. The dresser shaft 51 is driven by a motor not shown in the figure to rotate, and the dresser 50 is rotated around the dresser shaft 51 by the rotation of the dresser shaft 51. The cylinder 53 moves the dresser 50 up and down via the dresser shaft 51, and presses the dresser 50 against the grinding surface 352a of the grinding pad 352 with a predetermined pressing force. In the grinding device of this embodiment, the dresser 50 is used to measure the wear amount of the grinding pad 352. That is, the dressing unit 356 is equipped with a displacement sensor 60 for measuring the displacement of the dresser 50. The displacement sensor 60 constitutes a wear amount detection means for detecting the wear amount of the grinding pad 352, and is arranged on the upper surface of the swing arm 55. A target plate 61 is fixed on the dresser shaft 51, and as the dresser 50 moves up and down, the target plate 61 moves up and down together. The displacement sensor 60 is arranged to be inserted through the target plate 61, and the displacement of the dresser 50 is measured by measuring the displacement of the target plate 61. In addition, as the displacement sensor 60, all types of sensors such as a linear scale, a laser sensor, an ultrasonic sensor, or an eddy current sensor can be used. In addition, the displacement sensor 60 and the target plate 61 can also be omitted.

[0045] The dressing of the grinding surface 352a of the grinding pad 352 is performed in the following manner. The dresser 50 is pressed against the grinding surface 352a by the cylinder 53, and at the same time, pure water is supplied to the grinding surface 352a from a pure water supply nozzle not shown in the figure. In addition, as a substitute for the pure water from the pure water supply nozzle not shown in the figure, or as an addition, the passage 353 and / or the grinding liquid supply nozzle 354 for supplying the grinding liquid can also be switched to supply pure water to supply pure water to the grinding surface 352a. In this state, the dresser 50 is rotated around the dresser shaft 51 and the swing arm 55 is swung on the grinding surface 352a, so that the lower surface (diamond particles) of the dressing component 50a is in sliding contact with the rotating grinding surface 352a. In this way, the grinding pad 352 is ground by the dresser 50 to dress the grinding surface 352a.

[0046] The polishing unit 300 includes a film thickness sensor 42, which measures the film thickness of the substrate WF on the polishing surface 352a. The film thickness sensor 42 is configured to generate a film thickness index value that directly or indirectly indicates the film thickness of the substrate WF. The film thickness index value changes according to the film thickness of the substrate WF. The film thickness index value may be a value indicating the film thickness of the substrate WF itself, or may be a physical quantity or signal value before conversion into film thickness.

[0047] Examples of the film thickness sensor 42 include an eddy current sensor and an optical film thickness sensor. The film thickness sensor 42 is provided in the polishing table 350 and rotates together with the polishing table 350. More specifically, the film thickness sensor 42 is configured to measure the film thickness at a plurality of measurement points of the substrate WF while traversing the substrate WF on the polishing surface 352a each time the polishing table 350 rotates one circle. The film thickness at the plurality of measurement points is output from the film thickness sensor 42 as a film thickness index value, and the film thickness index value is sent to the control device 900. The control device 900 is configured to control the operation of the top ring 302 based on the film thickness index value.

[0048] The control device 900 generates a film thickness profile of the substrate WF based on the film thickness index value output from the film thickness sensor 42. The film thickness profile of the substrate WF is the distribution of the film thickness index value. The control device 900 controls the operation of the top ring 302 so that the difference between the current film thickness profile of the substrate WF obtained and the target film thickness profile is eliminated. The target film thickness profile of the substrate WF is pre-stored in the storage device 900b of the control device 900. Examples of the current film thickness profile of the substrate WF include: Figure 1 The initial film thickness profile of the substrate WF before polishing by the substrate processing apparatus 1000 (polishing unit 300) shown in FIG. Figure 1 The film thickness profile is created from the film thickness index value output from the film thickness sensor 42 when the substrate processing apparatus 1000 shown in the figure polishes the substrate WF. The initial film thickness profile is created based on the film thickness measurement value obtained by the independent film thickness measurement device not shown in the figure or the film thickness measurement value obtained by another substrate processing apparatus 1000 equipped with a film thickness sensor. The initial film thickness profile is stored in the storage device 900b of the control device 900.

[0049] <Drying unit>

[0050] The drying unit 500 is a device for drying the substrate WF. Figure 1 In the substrate processing apparatus 1000 shown in FIG. 1 , the drying unit 500 dries the substrate WF that has been polished in the polishing unit 300 and then cleaned in the cleaning unit of the transport unit 200 . Figure 1As shown, the drying unit 500 is arranged downstream of the conveying unit 200. The drying unit 500 has a nozzle 530 for spraying gas to the substrate WF conveyed on the conveying roller 202. The gas may be, for example, compressed air or nitrogen. The substrate WF may be dried by blowing off water droplets on the conveyed substrate WF through the drying unit 500.

[0051] <Uninstall unit>

[0052] The unloading unit 600 is a unit that carries out the substrate WF after being subjected to processes such as polishing and cleaning to the outside of the substrate processing apparatus 1000 . Figure 1 In the substrate processing apparatus 1000 shown in FIG. 1 , the unloading unit 600 receives the substrate after being dried in the drying unit 500. Figure 1 As shown, the unloading unit 600 is disposed downstream of the drying unit 500. In one embodiment, the unloading unit 600 is constructed according to the mechanical device interface standard (IPC-SMEMA-9851) of SMEMA (Surface Mount Equipment Manufacturers Association).

[0053] <Top Ring>

[0054] Next, the top ring 302 in the polishing unit 300 according to one embodiment will be described. Figure 3 and Figure 4 This is a cross-sectional view schematically showing a top ring 302 according to one embodiment. Figure 3 1 is a cross-sectional view showing the top ring 302 when the substrate WF is brought into contact with the polishing pad 352 and the diaphragm 422 and the piezoelectric element 432 are in a pressurized state. Figure 4 3 is a cross-sectional view of the top ring 302 when the substrate WF is not in contact with the polishing pad 352 and the diaphragm 422 and the piezoelectric element 432 are in a non-pressurized state.

[0055] The top ring 302 includes a substrate adsorption member 410, a base member 420, and a piezoelectric element member 430 disposed between the substrate adsorption member 410 and the base member 420. The substrate adsorption member 410, the base member 420, and the piezoelectric element member 430 are configured to be slidable in the up-down direction relative to each other, and the piezoelectric element member 430 is slidable in the up-down direction relative to the base member 420 and the substrate adsorption member 410.

[0056] The substrate adsorption component 410 is arranged below the base component 420 and the piezoelectric element component 430, and includes a porous component 411 and a shielding component 412 on which the porous component 411 is mounted. The porous component 411 can be any component that can vacuum adsorb the substrate WF by vacuuming using the decompression means (vacuum source) 415, and can be, for example, composed of a resin 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 addition, the porous component 411 can also be composed of ceramics in which a large number of pores are formed. In this embodiment, the porous component 411 is formed in a plate shape, and has a substrate adsorption surface 411a for adsorbing the substrate WF and a decompression portion 411b connected to the decompression means (vacuum source) 415. The porous component 411 is decompressed by the decompression means (vacuum source) 415, and the substrate WF is adsorbed and held on the porous component 411.

[0057] The shielding member 412 only needs to be an airtight member that can shield the flow of gas, and can be formed of, for example, a relatively soft resin plate such as PE (polyethylene), PP (polypropylene), PTFE (polytetrafluoroethylene) or PVC (polyvinyl chloride). In the present embodiment, the shielding member 412 is formed to shield the surface and side surface of the porous member 411 opposite to the substrate adsorption surface 411a. The shielding member 412 includes a suction hole 414 formed to communicate with the porous member 411. The decompression portion 411b is provided at a position where the suction hole 414 is formed. In the present embodiment, the suction hole 414 is formed in the shielding member 412 in a manner that is communicated with the side surface of the porous member 411, and the decompression portion 411b is provided on the side surface of the porous member 411. One end of the suction hole 414 is connected to the side surface of the porous member 411, and the other end is connected to the decompression means 415 via the suction path 423.

[0058] By providing the shielding member 412, when the porous member 411 is evacuated by the decompression means (vacuum source) 415, a negative pressure can be efficiently formed on the substrate adsorption surface 411a. As a result, the substrate WF can be reliably adsorbed to the substrate adsorption member 410, so that it is not necessary to provide a retainer member around the substrate WF, and the substrate WF can be prevented from flying (slipping) to the outside during polishing. In addition, the substrate WF or the top ring 302 can be prevented from contacting with the retainer member and being damaged during polishing.

[0059] The substrate adsorption member 410 includes a frame member 413, which is provided on the shielding member 412 to surround at least a portion of the piezoelectric element member 430. The frame member 413 is provided in a frame shape at the peripheral portion of the upper surface of the shielding member 412. The substrate adsorption member 410 is configured to guide the movement of the substrate adsorption member 410 relative to the piezoelectric element member 430 and further relative to the base member 420 in the vertical direction by the support rollers 438 provided around the piezoelectric element member 430. On the inner side surface of the frame member 413, as shown in FIG. Figure 6 As shown, a support pad 418 is provided corresponding to each support roller 438. The support pad 418 is guided by contact with the support roller 438, thereby guiding the substrate adsorption component 410 to move in the up-down direction relative to the piezoelectric element component 430. In addition, the support pad 418 may be provided in common with respect to a plurality of support rollers 438. The substrate adsorption component 410 is mounted on the piezoelectric element component 430 in a manner that allows it to move slightly relative to the piezoelectric element component 430 in a planar direction parallel to the polishing surface of the polishing pad 352. In addition, in the frame component 413, stoppers 413A (see FIG. 4 ) for limiting the downward movement of the substrate adsorption component 410 are provided corresponding to the four corners of the piezoelectric element component 430. Figure 6 ).

[0060] In addition, the top ring 302 further includes an outer peripheral band 419, which connects the outer side surface of the base body 421 of the base member 420 and the outer side surface of the frame member 413 of the substrate adsorption member 410. The outer peripheral band 419 is provided to surround the entire circumference of the top ring 302. The outer peripheral band 419 allows the displacement of the substrate adsorption member 410 relative to the base member 420, and prevents the polishing liquid and the like from entering the space (internal space) between the substrate adsorption member 410 and the base member 420. In this example, the concave portion opened at the bottom of the base member 420 and the concave portion opened at the top of the substrate adsorption member 410 form the internal space.

[0061] The base member 420 includes a base body 421 connected to the top ring shaft 18, and a diaphragm (elastic membrane) 422 mounted on the base body 421 to form a pressurized chamber 422A. The diaphragm (elastic membrane) 422 can be made of, for example, silicone rubber, FKM, or EPDM. The base body 421 has a recessed portion, i.e., an internal space, which is open at the bottom. The diaphragm 422 is arranged above the internal space (on the bottom side of the recessed portion), and at least a portion of the piezoelectric element member 430 is accommodated below the diaphragm 422. The pressurized chamber 422A in the diaphragm 422 is connected to the compressed air supply source 425 via the flow path 424, and the diaphragm 422 is configured to be pressurized and expanded by the compressed air (pressurized fluid) from the compressed air supply source 425.

[0062] like Figure 3 and Figure 5As shown, linear guides 426 are provided on two opposite inner sides of the base body 421. In this example, as shown in FIG. Figure 5 As shown, two linear guides 426 are respectively provided on two opposing inner side surfaces. The linear guides 426 engage with the linear guides 437 provided at the corresponding positions of the piezoelectric element component 430, and guide the piezoelectric element component 430 to move up and down relative to the base component 420. For example, one of the linear guides 426 and the linear guides 437 may be a track, and the other may be a sliding component engaged with the track. In this example, among the four inner side surfaces of the base body 421, linear guides are provided only on a pair of opposing inner side surfaces (two inner side surfaces), so that the base component 420 and the piezoelectric element component 430 can move up and down smoothly. In addition, as long as there is no special obstacle to the up and down movement between the base component 420 and the piezoelectric element component 430, linear guides 426 may be provided on all the inner side surfaces of the base body 421.

[0063] The piezoelectric element component 430 includes: a holding body (holding member) 431 as a housing; a plurality of piezoelectric elements 432 housed and arranged inside the holding body 431; a fluid bag 433 arranged below each piezoelectric element 432; and a pressing force measuring device 434 arranged between the piezoelectric element 432 and the fluid bag 433. The pressing force measuring device 434 may be arranged below the fluid bag 433 or at other positions as long as it can measure the pressing force by each piezoelectric element 432 (the pressing force of pressing the substrate WF against the polishing pad 352 at the position of each piezoelectric element 432).

[0064] For example Figure 6 As shown, the plurality of piezoelectric elements 432 are arranged in a matrix shape. However, the plurality of piezoelectric elements 432 are not limited to Figure 6 The configuration can be any configuration. It is preferable that each piezoelectric element 432 has substantially the same size and characteristics. The characteristics of the piezoelectric element include the amount of elongation (stroke) relative to the applied voltage, etc. Each piezoelectric element 432 is connected to the driving voltage applying device 435 via the power wiring 436. Although this example shows an example in which the driving voltage applying device 435 is built into the base body 421, the driving voltage applying device 435 can also be arranged outside the top ring 302. The driving voltage applying device 435 receives a control signal / voltage from the control device 900, and supplies a driving voltage corresponding to the control signal / voltage to each piezoelectric element 432. Each piezoelectric element 432 constitutes an independent actuator, which can apply a pressing force to each part of the substrate adsorption component 410 (each area corresponding to each piezoelectric element) completely independently of each other.

[0065] The fluid bag 433 is a part that holds the fluid inside a bag body made of a material with low elasticity (high-hardness silicone rubber, EPDM, FKM or nylon film, polyethylene film, PET film, and a film formed by these films as a multi-layer structure, etc., which is equivalent to the bag material of a commercially available emergency water bag, etc.), and the whole constitutes a bag body component with low elasticity (the bag body component / bag will deform with the shape of the fluid placed therein, but the bag body component / bag will not expand, that is, a non-expandable bag body component / bag). That is, the fluid bag 433 is a component that transmits the pressure caused by the piezoelectric element 432 to the substrate adsorption component 410 with almost no expansion or contraction. In order to further avoid the expansion and contraction of the fluid bag 433, the fluid held by the fluid bag 433 should preferably be a non-compressible fluid, such as a liquid such as water or oil. In addition, the liquid should be fully filled in the bag body of the liquid bag 433 so that the liquid bag 433 becomes a component with low elasticity after being filled with liquid. However, even if the fluid held by the fluid bag 433 is gas, the fluid may be gas if the fluid bag 433 as a whole can constitute a component with low elasticity. In this case, it is also preferable to fully fill the bag body of the fluid bag 433 with gas. In this way, the pressure can be uniformly transmitted to the area directly below each piezoelectric element 432 in the substrate adsorption component 410 through the fluid bag 433 with low elasticity, so that the pressure transmitted to each part of the substrate adsorption component 410 can be uniform.

[0066] In this embodiment, if Figure 3 and Figure 4 As shown in FIG. 1 , although a thin partition is provided between adjacent fluid bags 433, the adjacent fluid bags 433 can press the substrate side (substrate adsorption member 410) substantially without gaps. Therefore, the fluid bags 433 provided on each piezoelectric element 432 can press the substrate adsorption member 410 and thus each part of the substrate WF (which can be pressed on the polishing pad 352) without gaps. In other words, the fluid bags 433 can reduce or prevent uneven pressing caused by each piezoelectric element 432.

[0067] When the driving voltage applying device 435 applies a driving voltage to the plurality of piezoelectric elements 432, the piezoelectric elements 432 will stretch toward the fluid bag 433. The stretching of the piezoelectric element 432 will partially adjust the pressing force of the pressurizing chamber 422A to press the substrate WF against the polishing pad 352. Thus, it is possible to suppress or prevent uneven pressing (uneven pressing force) of the pressurizing chamber 422A to press the substrate WF against the polishing pad 352 via the piezoelectric element 432. Hereinafter, the stretching amount of the piezoelectric element is sometimes referred to as a stroke. In this way, the piezoelectric element 432 to which the driving voltage is applied can adjust the pressing force of the substrate WF against the polishing pad 352 for each region of each piezoelectric element 432. Therefore, even if the thickness of the "porous component 411, substrate, etc." (substrate WF, porous component 411 and / or shielding component 412) is uneven, the stroke of the piezoelectric element can be appropriately adjusted corresponding to the uneven thickness of the substrate WF, etc., and each part (area) of the substrate WF can be pressed against the polishing pad 352 with a uniform pressing force (the surface pressure distribution can be uniformized), thereby improving the in-plane uniformity of the polishing rate.

[0068] For example, in the case where the substrate WF has an uneven thickness, when various parts (regions) of the substrate WF are pressed with a uniform stroke based on the pressurizing chamber 422A, the parts with a larger thickness will be pressed against the polishing pad 352 with a larger pressing force, and the parts with a smaller thickness will be pressed against the polishing pad 352 with a smaller pressing force. However, according to this embodiment, by adjusting the stroke of the piezoelectric element located at the part with a larger thickness (the part where the polishing rate tends to increase) to be relatively smaller than the stroke of the piezoelectric element located at the part with a smaller thickness (the part where the polishing rate tends to decrease), the pressing force of the pressurizing chamber 422A that presses the substrate WF against the polishing pad 352 can be made uniform at various parts (regions) of the substrate WF (the surface pressure distribution can be made uniform). In the case where the porous member 411 and / or the shielding member 412 have uneven thickness, the stroke of the piezoelectric element can be appropriately adjusted at each part (region) of the substrate WF, so that the pressing force of the pressurizing chamber 422A pressing the substrate WF against the polishing pad 352 becomes uniform at each part (region) of the substrate WF (the surface pressure distribution can be made uniform). In this way, according to the present embodiment, even if the thickness of the substrate WF, the porous member 411 and / or the shielding member 412 is uneven, the stroke of the piezoelectric element can be appropriately adjusted corresponding to the uneven thickness of the substrate WF, the porous member 411 and / or the shielding member 412, so that each part (region) of the substrate WF can be pressed against the polishing pad 352 with a uniform pressing force (the surface pressure distribution can be made uniform), thereby improving the in-plane uniformity of the polishing rate.

[0069] The pressure measuring device 434 is a device that measures the pressure (force pressing the substrate WF against the polishing pad 352) of the position of each piezoelectric element 432, and may be, for example, a pressure gauge. In the present embodiment, each pressure measuring device 434 is arranged in series with the piezoelectric element 432 and the fluid bag 433. More specifically, each pressure measuring device 434 is arranged between the piezoelectric element 432 and the fluid bag 433. The pressure measuring device 434 thus arranged can measure the pressure of each piezoelectric element 432 pressing the substrate WF against the polishing pad 352, respectively. The arrangement of the pressure measuring device 434 is not limited to Figure 3 and Figure 4 As long as the pressing force of each piezoelectric element 432 pressing the substrate WF against the polishing pad 352 can be measured, the pressing force measuring device 434 may be disposed between the substrate suction member 410 and the fluid bag 433 or beside the fluid bag 433 .

[0070] The pressing force measuring device 434 may also be configured to convert the measured pressing force [N] into pressure [Pa]. Examples of the pressing force measuring device 434 include a force gauge or a piezoelectric sheet connected to a plurality of piezoelectric elements 432. The piezoelectric sheet has a plurality of piezoelectric sensors configured to generate a voltage corresponding to the force applied to the piezoelectric sheets and convert the voltage value into force or pressure.

[0071] like Figure 5 As shown in FIG. 1 , linear guides 437 are provided on two opposite outer sides of the holder 431 of the piezoelectric element component 430. In this example, two linear guides 437 are provided on each outer side of the holder 431. The linear guides 437 engage with the linear guides 426 of the base component 420 to guide the piezoelectric element component 430 to move up and down relative to the base component 420. Figure 5 As shown, four stoppers 421A are provided on the base body 421 of the base member 420 corresponding to the four corners of the piezoelectric element member 430. These stoppers 421A restrict the downward movement of the piezoelectric element member 430.

[0072] like Figure 3 and Figure 6 As shown, a plurality of support rollers 438 are provided on each outer side surface of the retaining body 431. In this example, three support rollers 438 are provided on each outer side surface of the main body 431, but the number of support rollers 438 is arbitrary. Figure 3 As shown in FIG. 1 , the support rollers 438 are provided below the linear guide 437. Corresponding to each support roller 438, a support pad 418 is provided on the inner side of the frame member 413 of the substrate adsorption member 410. Each support roller 438 rotates on the support pad 418 to guide the substrate adsorption member 410 and the piezoelectric element member 430 to move up and down. Figure 6As shown, four stoppers 413A are provided on the frame member 413 of the substrate adsorption member 410 corresponding to the four corners of the piezoelectric element member 430. These stoppers 413A restrict the substrate adsorption member 410 from moving downward relative to the piezoelectric element member 430.

[0073] That is, in Figure 4 In the state of being held, the piezoelectric element member 430 is restricted from moving downward relative to the base member 420 by the stopper 421A of the base member 420, and the substrate adsorption member 410 is restricted from moving downward relative to the piezoelectric element member 430 by the stopper 413A of the substrate adsorption member 410. In addition, a stopper (not shown) for restricting the piezoelectric element member 430 from moving upward relative to the base member 420 may be provided on the inner side surface of the base body 421. Such a stopper may be provided, for example, so that the inner wall of the base body 421 protrudes toward the top of the four corners of the holder 431 of the piezoelectric element member 430.

[0074] Figure 7 It is a modified example of the frame member of the substrate adsorption member. As shown in the same figure, it is also possible to configure so that part of the stopper 413A of the frame member 413 can be unloaded from another part of the frame member 413. For example, the stopper 413A can be detachably connected to another part of the frame member 413 by a fastening member 413B such as a screw. By configuring in this way, the stopper 413A can be unloaded, and the substrate adsorption member 410 can be easily unloaded from the top ring 302. Thus, maintenance such as replacement of a porous member as a consumable included in the substrate adsorption member can be easily performed. In addition, in the case of unloading the substrate adsorption member 410 from the top ring 302, it is also possible to configure so that only a part of the stopper 413A can be unloaded, without unloading all four stoppers 413A.

[0075] exist Figure 4 In the unpressurized state of the top ring 302 shown, the top ring 302 (substrate WF) is not in contact with the polishing pad 352. In addition, no driving voltage is applied to the piezoelectric element 432 of the piezoelectric element component 430 (the piezoelectric element is in an unpressurized state). In addition, sufficient compressed air is not introduced into the pressurized chamber 422A, and the diaphragm 422 is not pressurized (unpressurized state). In the piezoelectric element component 430, the four corners of its holding body 431 are lowered relative to the base component 420 to the stopper 421A ( Figure 5 ) is engaged, the substrate adsorption component 410 is lowered relative to the piezoelectric element component 430 to its stopper 413A ( Figure 6 ) until the four corners of the piezoelectric element component 430 are engaged.

[0076] exist Figure 3In the pressurized state of the top ring 302 shown, the substrate WF held by the top ring 302 contacts the polishing pad 352, and a pressurized fluid is introduced into the pressurized chamber 422A, so that the diaphragm 422 expands and presses the piezoelectric element component 430 downward, and the substrate adsorption component 410 is pressed downward via the plurality of piezoelectric elements 432 and the fluid bag 433, thereby pressing the substrate WF against the polishing pad 352. In addition, the stroke of each piezoelectric element 432 is adjusted, and the pressing force applied to each portion (each region) of the substrate WF from the pressurized chamber 422A via each piezoelectric element 432 is adjusted. That is, the substrate WF is pressed against the polishing pad 352 by the pressing force based on the diaphragm 422, and the pressing force applied to each portion (each region) of the substrate WF is adjusted by the plurality of piezoelectric elements 432, so that the surface pressure distribution of the pressing force of the pressurized chamber 422A pressing the substrate WF against the polishing pad 352 is uniform.

[0077] In this structure, the substrate WF is pressed against the polishing pad 352 by the pressing force caused by the diaphragm 422 on the entire area of ​​the substrate WF, and the pressing force of each area of ​​the substrate WF is adjusted by the stroke of the plurality of piezoelectric elements 432 corresponding to each area of ​​the substrate WF, so even if the thickness of the porous member 411, the shielding member 412 and / or the substrate WF is uneven, each part of the substrate WF can be pressed against the polishing pad 352 with a uniform force (the surface pressure distribution can be made uniform). Thus, the in-plane uniformity of the polishing rate (polishing amount) can be improved.

[0078] The film thickness control based on the grinding process of the above-mentioned substrate processing device 1000 can be performed as follows, for example. The control device 900 calculates the difference between the current film thickness profile of the substrate WF (the film thickness profile of the substrate WF produced according to the film thickness index value (the index value directly or indirectly indicating the film thickness of the substrate WF) output by the film thickness sensor 42) and the target film thickness profile pre-stored in the storage device 900b, and produces the distribution of the target grinding amount of the ground surface of the substrate WF. Then, the control device 900 determines the command value of the voltage to be applied to the piezoelectric element 432 to achieve the target grinding amount within the prescribed grinding time based on the distribution of the produced target grinding amount. For example, the control device 900 produces the distribution of the target grinding rate based on the distribution of the target grinding amount and the above-mentioned prescribed grinding time, and then determines the command value of the voltage that can achieve the target grinding rate based on the grinding rate related data. The grinding rate related data is data indicating the relationship between the grinding rate and the command value of the voltage.

[0079] The control device 900 sends the voltage command value (control signal / voltage) to the driving voltage applying device 435. The driving voltage applying device 435 applies a predetermined driving voltage to the piezoelectric element 432 according to the voltage command value (control signal / voltage) to adjust the film thickness profile of the substrate WF. In addition, during the polishing of the substrate WF, the film thickness profile is adjusted, for example, at a fixed time or at a cycle of one rotation of the polishing table 350.

[0080] In another example of the operation of the top ring 302, the control device 900 does not create a distribution of the target polishing amount, but determines the command value of the voltage to be applied to the piezoelectric element 432 based on the current film thickness profile of the substrate WF obtained by the film thickness sensor 42. For example, when the target film thickness profile is a flat film thickness profile, the control device 900 determines the following voltage command value in order to make the current film thickness profile close to the flat film thickness profile: a voltage higher than the currently applied voltage by a predetermined amount of change is applied to the piezoelectric element 432 corresponding to the area with a large film thickness index value (a pointer value directly or indirectly indicating the film thickness of the substrate WF generated by the film thickness sensor 42), and a voltage lower than the currently applied voltage by a predetermined amount of change is applied to the piezoelectric element 432 corresponding to the area with a small film thickness pointer value. In addition, the amount of change of these voltages is pre-set in the control device 900 as a parameter.

[0081] (Correction)

[0082] The calibration of the plurality of piezoelectric elements 432 is described. The calibration of the piezoelectric elements 432 is aimed at adjusting the relationship between the applied voltage (stroke) of each piezoelectric element 432 and the uniformity of the surface pressure distribution when the substrate WF is pressed against the polishing pad 352 (taking into account the pressing force difference caused by the unevenness of the deformation hysteresis of the piezoelectric element 432, the installation height of the piezoelectric element 432, and the thickness of the substrate adsorption component 410 (porous component 411, shielding component 412)).

[0083] (An example of calibration method)

[0084] Figure 8 1 is an explanatory diagram for explaining an example of a calibration method for the top ring. In this calibration method, a surface pressure distribution measuring device 500 is placed on the polishing pad 352, and a top ring 302 with a substrate WF adsorbed thereon is placed on the surface pressure distribution measuring device 500. The pressure chamber 422A ( Figure 3 ) to supply compressed air to press the substrate WF against the polishing pad 352. In addition, at this time, the porous member 411 ( Figure 3) is pressed against the polishing pad 352. The surface pressure distribution measuring device 500 may be, for example, a sheet-shaped pressure sensor or a tactile sensor. In addition, the pressure sensing portion of the surface pressure distribution measuring device 500 is sized to cover the entire substrate WF, so that the surface pressure distribution measuring range of the surface pressure distribution measuring device 500 is configured to be larger than the size of the substrate WF.

[0085] Then, in the computer (PC) 501 connected to the surface pressure distribution measuring device 500, the pressure distribution measured by the surface pressure distribution measuring device 500 is observed, and the strokes (voltage values) of the plurality of piezoelectric elements 432 are adjusted so that the output (pressure distribution) of the surface pressure distribution measuring device 500 becomes uniform. At this time, automatic correction can also be performed by artificial intelligence. The voltage value of the piezoelectric element 432 obtained above is stored as a correction value in a storage device inside or outside the computer (PC) 501. As the computer 501, a control device 900 can also be used.

[0086] According to this method, even if the top ring 302 does not include the pressing force measuring device 434 ( Figure 3 ) in the case of, the piezoelectric element 432 can also be calibrated.

[0087] As another method, the stroke of the piezoelectric element can also be determined based on the actual grinding result (distribution of grinding rate) (see Japanese Patent Application Publication No. 2021-154421). All disclosures including the specification, claims, drawings and abstract of Japanese Patent Application Publication No. 2021-154421 are incorporated herein by reference in their entirety.

[0088] (Another example of calibration method)

[0089] Fig. 9 This is an explanatory diagram for explaining another example of the top ring correction method. Fig.10 This is a flowchart of the calibration of the piezoelectric element. In this example, a sequence including a binary representation of the voltage value applied to each piezoelectric element 432 is used as genetic data, and the voltage value of each piezoelectric element 432 is calibrated by a genetic algorithm (GA).

[0090] For example, when the applied voltage range of the piezoelectric element 432 is 0 to 5 [V], the number of divisions of the applied voltage range is set to 2. 7=128. When the voltage value expressed in binary is set to "1001011", 1001011 (binary) = 75 (decimal), 75 / 128×5[V]≈2.93[V]. By reversing these calculation sequences, the voltage of the piezoelectric element 432 can be binarized. That is, in the case of binarizing V1 (decimal), it is sufficient to calculate V1 (decimal) / 5×128=V1' (the voltage value based on the division number, decimal), and express V1' in binary. In addition, V1 is approximated to an integer here and then binarized. For example, in the case of V1=3[V], V1'=76.8, and is binarized as V1'=76.8≈77 (expressed in binary). An example of binarizing the voltage values ​​of each piezoelectric element 432 in this way is shown in Fig. 9 In addition, the value V1' including decimals can also be binarized.

[0091] In the same figure, xa represents gene data (data equivalent to genes). Here, a case where N (≥2) gene data x1, x2, ...xa..., xN are prepared is shown. n (≥2) represents the total number of piezoelectric elements 432, and i represents the number for identifying each piezoelectric element 432 (the i-th piezoelectric element). For example, gene data x1 includes the voltage value "0111001" of piezoelectric element No. 1, the voltage value "0110001" of piezoelectric element No. 2, the voltage value "0110011" of piezoelectric element No. 3, ... the voltage value "0110011" of piezoelectric element No. n. The same is true for gene data x2, x3, ..., xN. The stroke (displacement) of the piezoelectric element can also be binarized instead of the voltage value applied to the piezoelectric element.

[0092] In this calibration method, multiple (N) such as Fig. 9 The gene data shown is stored in a memory such as a storage device 900b. Then, voltage is applied to each piezoelectric element 432 according to the gene data to obtain Figure 3 The pressure measuring device 434 measures the pressure when the substrate WF is pressed against the polishing pad 352 in the state of being pressed, and then calculates the evaluation function value (standard deviation) σ (one σ value is obtained for a set of gene data) according to formula 1 based on these pressure values.

[0093] [Formula 1]

[0094]

[0095] σ: standard deviation

[0096] n: number of piezoelectric elements

[0097] i: piezoelectric element number

[0098] Pi: pressure measurement value of the i-th piezoelectric element by the pressure measuring device

[0099] [Formula 2]

[0100]

[0101] : Average value of the pressure measurement values ​​of the pressure measuring device of the piezoelectric elements 1 to n

[0102] When any standard deviation σ of the N gene data is above σT (allowable value), selection, crossover and / or sudden mutation are performed in the N gene data. On the other hand, when the standard deviation σ of the N gene data is less than σT, the gene data with the smallest σ is selected as the correction value and stored in the storage device (memory) among the gene data that satisfies the standard deviation σ. In addition, σT is the allowable value of the standard deviation σ. As long as it is less than this value, it can be set to a value that can be allowed as the surface pressure distribution.

[0103] "Selection" means that among the gene data 1 to N, a set number of excellent genes (here, gene data with a small σ) are retained, and the rest are replaced with random gene data. That is, the poor gene data are eliminated and the excellent gene data are retained. "Crossover" means that in the values ​​of the gene data x1...xN, a part of the values ​​(1 or more values) are replaced with each other. For example, the value "0" of the third bit of the voltage value of the piezoelectric element No. 1 of the gene data x2 is replaced with the value "1" of the fifth bit of the voltage value of the piezoelectric element No. 1 of the gene data x3. Parts of two or more consecutive numerical values ​​can also be replaced between different gene data. "Sudden mutation" means randomly selecting a part of the values ​​of the gene data x1...xN and inverting it (0 to 1 or 1 to 0).

[0104] When any standard deviation σ of the N gene data is greater than σT, the selection, crossover and / or sudden mutation of the N gene data are repeated, and the pressure distribution of the piezoelectric element and the standard deviation σ are measured for each gene data until gene data with a standard deviation σ less than σT is detected.

[0105] In addition, the initial values ​​of the N gene data may be completely random gene data, or a combination of voltages that is likely to make the surface pressure distribution uniform obtained in advance by experiments may be used as part of the gene data. This can be expected to accelerate the convergence of the correction (that is, the number of measurements required for correction can be reduced).

[0106] Reference Fig.10 An example of a flowchart for calibration of a piezoelectric element will be described.

[0107] In step S11, the identification number a of the gene data is set to 1, and calibration is started.

[0108] In step S12, the voltage value of the gene data a is applied to each piezoelectric element to obtain Figure 3 The measured values ​​(measured pressure distribution / surface thickness distribution) of the pressure measuring device 434 of each piezoelectric element in the state are used to calculate the standard deviation σa corresponding to the gene data No. a by formula 1 and stored in the storage device 900b, etc.

[0109] In step S13, it is determined whether a=N. If not, a=a+1 is set in step S14, and the process from step S12 is repeated. On the other hand, if a=N, the process moves to step S15. That is, the process of S12-S14 is repeated until the pressure distribution is measured for all the N gene data and the standard deviation σ1...σN with respect to all the N gene data is calculated.

[0110] In step S15, it is determined whether the smallest standard deviation σmin among the standard deviations σ1…σN of the N gene data is smaller than the allowable value σT. In addition, it is also possible to determine whether any of the standard deviations σ1…σN of the N gene data is smaller than σT by any other arbitrary method. In this case, in S17, the smallest standard deviation σa (a=1…N) that satisfies the requirement of being smaller than σT or any other standard deviation can be selected as the correction value.

[0111] In step S15, as long as the standard deviation σmin is above the allowable value σT, in S16, selection, crossover and / or mutation processing is performed on the N genetic data x1...xN, and new N genetic data x1...xN are produced. After a=1 is reset, the processing starting from step S12 is repeated on the produced new N genetic data x1...xN.

[0112] In step S15, if the standard deviation σmin is smaller than the allowable value σT, the process proceeds to step S17. In step S17, the gene data (correction value) corresponding to the standard deviation σmin being smaller than the allowable value σT is stored in the storage device 900b, etc., and the correction is completed. Alternatively, the voltage value (binary) included in the gene data may be converted into a decimal system and the decimal voltage value may be stored in the storage device 900b, etc., instead of storing the binary data gene data in the storage device 900b, etc.

[0113] (Other embodiments)

[0114] (1) In the above, a top ring having a plurality of piezoelectric elements is cited as an example, but a plurality of actuators of other types that can generate a plurality of pressing forces completely independently of each other may be used instead of the piezoelectric elements. Examples of actuators constituting such a plurality of actuators include hydraulic actuators such as hydraulic cylinders and motors, pneumatic actuators such as pneumatic motors and pneumatic cylinders, electric actuators such as electric motors, magnetic strain actuators such as magnetic strain elements, electromagnetic actuators such as linear motors, and small pistons.

[0115] (2) Although a quadrilateral substrate is used as an example above, the above embodiment can also be applied to a top ring for grinding a circular wafer.

[0116] (3) In the above, although the example is given of a structure in which the pressure of the pressurizing chamber 422A (diaphragm 422) pressing each part (each area) of the substrate WF against the polishing pad 352 is locally adjusted by a plurality of piezoelectric elements 432, the pressurizing chamber 422A (diaphragm 422) may be omitted, and the height of the top ring 302 may be adjusted by the up-and-down moving mechanism 319. After the height is maintained at which the substrate WF is in contact with or pressed against the polishing pad 352 with a small pressing force, the plurality of piezoelectric elements 432 press each part (each area) of the substrate WF to adjust the pressing force applied to each part (each area) of the substrate WF.

[0117] Several embodiments of the present invention are described above, but the embodiments of the invention described above are for easy understanding of the present invention and do not limit the present invention. The present invention can be changed and improved as long as it does not deviate from its main purpose, and the present invention certainly includes its equivalents. In addition, within the scope of solving at least part of the above-mentioned problems or within the scope of exerting at least part of the effects, the constituent elements described in the scope of the patent application and the specification can be arbitrarily combined or omitted.

[0118] In the present application, as one embodiment, a top ring is disclosed for holding a substrate, comprising: a base member connected to a rotating shaft; a substrate adsorption member, the substrate adsorption member including a porous member having a substrate adsorption surface for adsorbing the substrate and a decompression portion connected to a decompression means; and a first pressurizing component, the first pressurizing component being arranged between the base member and the substrate adsorption member, and having a plurality of first pressurizing means arranged on the side of the substrate adsorption member opposite to the substrate adsorption surface, each first pressurizing means being configured to be able to apply a pressing force to the substrate adsorption member completely independently of each other. The plurality of first pressurizing means capable of applying a pressing force completely independently of each other are, for example, pressurizing members (piezoelectric elements, etc.) driven by respective independent actuators.

[0119] According to this method, the plurality of first pressing means of the top ring press the substrate against the polishing pad via the porous member, and the pressing force of each first pressing means can be adjusted completely independently / individually. Therefore, even in the case where the porous member, the shielding member supporting the porous member, and / or the substrate have uneven thickness, the pressing force of each first pressing means can be adjusted individually, and each part (region) of the substrate can be pressed against the polishing pad with a uniform pressing force, which can improve the in-plane uniformity of the polishing rate. As a result, the polished layer on the substrate can be polished with a more uniform polishing amount.

[0120] Furthermore, in the present application, as one embodiment, a top ring is disclosed, wherein the first pressurizing component also has a retaining body for retaining the plurality of first pressurizing means, and the base component also has a second pressurizing means for pressing the retaining body on a side opposite to the plurality of first pressurizing means with fluid pressure.

[0121] According to this method, the pressing force of pressing the entire substrate can be adjusted by the second pressing means, while the pressing force on each part of the substrate can be adjusted by the plurality of first pressing means, so that each part of the substrate can be pressed against the polishing pad with a desired uniform pressing force. In other words, the pressing force of pressing the substrate against the polishing pad is mainly generated by the second pressing means, and the plurality of first pressing means (for example, a plurality of piezoelectric elements) can be used as a means of adjusting the pressing force on each area of ​​the substrate (a means of making the surface pressure distribution uniform). For example, by controlling the stroke of each piezoelectric element, the pressing force on each area of ​​the substrate by the second pressing means can be adjusted, and the surface pressure distribution of the entire area of ​​the substrate can be made uniform.

[0122] Furthermore, in the present application, as one embodiment, a top ring is disclosed, wherein the first pressurizing assembly further comprises a fluid bag with low elasticity, which is provided on the substrate adsorption component side of each pressurizing means. The fluid bag with low elasticity can be provided, for example, with a structure in which a non-expandable bag body component made of a material with low elasticity is fully filled with fluid.

[0123] According to this aspect, the pressing force from each first pressurizing means is transmitted to the porous member via the non-expandable fluid bag with low elasticity, thereby reducing uneven pressing by each first pressurizing means. As a result, appropriate pressing force can be applied to the entire area of ​​the substrate without gaps.

[0124] Furthermore, in the present application, as one embodiment, a top ring is disclosed, wherein the fluid bag holds a liquid.

[0125] According to this aspect, by retaining liquid as the fluid, a non-expandable fluid bag with low stretchability can be easily configured.

[0126] Furthermore, in the present application, as one embodiment, a top ring is disclosed, wherein the first pressurizing member is configured to be movable in a vertical direction relative to the base member and the substrate adsorption member.

[0127] According to this method, the first pressure assembly moves relative to the base member, so that the first pressure assembly can be easily pressed in the direction of the substrate by configuring an additional pressure means (second pressure means) on the base member. In this case, the pressing force for pressing the substrate against the polishing pad is mainly generated by the second pressure means, and multiple first pressure means (for example, multiple piezoelectric elements) can be used as a means for adjusting the pressing force on each area of ​​the substrate (a means for making the surface pressure distribution uniform). In addition, the first pressure assembly moves relative to the substrate adsorption member, so even if the porous member, the shielding member supporting the porous member and / or the substrate have uneven thickness, the substrate adsorption member and the substrate can be easily pressed against the polishing pad by the additional pressure means (second pressure means) via the first pressure assembly. Furthermore, because the first pressure assembly moves relative to the substrate adsorption member, and the base member is in a fixed position relative to the polishing pad, even if the thickness of the substrate changes and / or the height position of the polishing surface of the substrate changes due to the wear of the polishing pad, the substrate can be pressed against the polishing pad evenly and stably.

[0128] Furthermore, in the present application, as one embodiment, a top ring is disclosed, wherein the base component and the substrate adsorption component are connected by a peripheral band, and the peripheral band seals the gap between the base component and the substrate adsorption component, and the first pressurizing component is sealed in a space surrounded by the base component, the substrate adsorption component and the peripheral band.

[0129] According to this aspect, the first pressurizing member can be protected from polishing liquid (slurry) and the like.

[0130] Furthermore, in the present application, as one embodiment, a top ring is disclosed, wherein a linear guide mechanism is provided between an inner side surface of the base component and an outer side surface of the first pressurizing assembly, and the linear guide mechanism guides the relative movement of the base component and the first pressurizing assembly.

[0131] According to this aspect, an appropriate positional relationship between the first pressurizing assembly and the base member can be maintained, and the two can be relatively moved (the first pressurizing assembly can be moved relative to the base member).

[0132] Furthermore, in the present application, as an embodiment, a top ring is disclosed, wherein, in a plan view, the first pressurizing assembly is a quadrilateral, and the linear guide mechanism is only provided on a pair of opposite outer side surfaces of the first pressurizing assembly.

[0133] According to this aspect, the relative movement between the first pressing member and the base member can be easily and smoothly performed.

[0134] Furthermore, in the present application, as one embodiment, a top ring is disclosed, wherein the first pressure component has a plurality of rollers arranged along the outer circumference of the first pressure component, and the plurality of rollers are used to guide the movement of the substrate adsorption component in the up and down directions relative to the first pressure component.

[0135] According to this aspect, the first pressurizing unit and the substrate suction member can maintain an appropriate positional relationship and can be relatively moved.

[0136] Furthermore, in the present application, as one embodiment, a top ring is disclosed, wherein the base component has a first stopper that limits the downward movement of the first pressure component relative to the base component, and the substrate adsorption component has a second stopper that limits the downward movement of the substrate adsorption component relative to the first pressure component.

[0137] According to this aspect, when the top ring is separated from the polishing pad and raised, it is possible to prevent various parts of the top ring from colliding with each other, falling off, etc., and ensure appropriate operation of the top ring.

[0138] Furthermore, in the present application, as one embodiment, a top ring is disclosed, wherein, when viewed from above, the base part, the substrate adsorption part and the first pressure component are quadrilaterals, the first stopper is arranged on the base part corresponding to the four corners of the first pressure component, and the second stopper is arranged on the substrate adsorption part corresponding to the four corners of the first pressure component.

[0139] According to this method, when the base component, the substrate adsorption component and the components of the first pressure assembly are quadrilaterals when viewed from above, by arranging the first stopper and the second stopper at the four corners of the base component and the substrate adsorption component, the range of relative movement between the components can be reliably limited with a simple structure.

[0140] Furthermore, in the present application, as one embodiment, a top ring is disclosed, wherein a part or all of the second stopper is configured to be removable together with the corner of the substrate adsorption component, and the substrate adsorption component can be removed from the first pressurizing component when a part or all of the second stopper is removed together with the corner of the substrate adsorption component.

[0141] According to this aspect, the substrate adsorption component can be removed from the top ring by partially or completely removing the second stopper, so that the substrate adsorption component is easy to disassemble, thereby making it easy to perform maintenance such as replacement of the porous component, which is a consumable part included in the substrate adsorption component.

[0142] Furthermore, in the present application, as one embodiment, a top ring is disclosed, wherein the substrate includes a substrate body and a plurality of wiring units arranged on the substrate body, and the size of each first pressurizing means corresponds to the size of each wiring unit. The substrate processing device sometimes grinds a substrate having a plurality of wiring units. The plurality of wiring units of such a substrate respectively have wiring patterns. In addition, the plurality of wiring units of the substrate after grinding may be respectively mounted with bare crystals of IC chips, etc.

[0143] According to this aspect, when the substrate includes a plurality of wiring units, each of the first pressing means can appropriately press each wiring unit to be polished, thereby polishing the height of the wiring pattern of each wiring unit to be flat.

[0144] Furthermore, in the present application, as an embodiment, a top ring is disclosed, wherein the substrate is a quadrilateral substrate.

[0145] According to this aspect, each portion of the square substrate, which tends to have a large uneven thickness, can be pressed against the polishing pad with a uniform pressing force, and polishing can be performed at a uniform polishing rate.

[0146] Furthermore, in the present application, as one embodiment, a top ring is disclosed, wherein each first pressurizing means is a piezoelectric element.

[0147] According to this aspect, by using a piezoelectric element as the first pressing means, it is possible to accurately control the pressing force applied to each portion of the substrate with a small and simple structure.

[0148] Furthermore, in the present application, as one embodiment, a top ring is disclosed, wherein the second pressurizing means is a diaphragm having a pressurizing chamber.

[0149] According to this aspect, by using the diaphragm as the second pressing means, it is possible to accurately control the pressing force for pressing the entire substrate with a small and simple structure.

[0150] Furthermore, in the present application, as one embodiment, a substrate processing device is disclosed, comprising: the above-mentioned top ring; a grinding table, the grinding table holds a grinding pad, the grinding pad is used to press the substrate held on the top ring; the decompression means, the decompression means is connected to the porous component; and a first control means, the first control means controls the pressing force based on each first pressurizing means.

[0151] According to this aspect, the above-mentioned effects are achieved. In particular, by controlling the pressing force by the plurality of first pressing means through the first control means, each portion of the substrate can be pressed against the polishing pad with a uniform pressing force.

[0152] Furthermore, in the present application, as one embodiment, a substrate polishing device is disclosed, wherein the first pressure component also has a holding body for holding the multiple first pressure means, the base component also has a second pressure means, and the second pressure means presses the side of the holding body opposite to the multiple first pressure means with fluid pressure, and the substrate processing device also has a second control means, which adjusts the pressing force based on the second pressure means.

[0153] According to this method, the above-mentioned effects are exerted. In particular, by controlling the pressing force based on the plurality of second pressure means through the second control means, it is possible to give the substrate as a whole an appropriate pressing force. In addition, the pressing force of pressing the substrate against the polishing pad is mainly generated by the second pressure means, and the plurality of first pressure means (for example, a plurality of piezoelectric elements) can be used as a means of adjusting the pressing force on each area of ​​the substrate (a means of making the surface pressure distribution uniform). For example, by controlling the stroke of each piezoelectric element (first pressure means), the pressing force from the second pressure means on each area of ​​the substrate is adjusted, and the surface pressure distribution of the entire area of ​​the substrate can be made uniform.

[0154] Furthermore, in the present application, as one embodiment, a substrate polishing device is disclosed, wherein the first control means adjusts the pressing force based on each first pressing means based on the measurement result of the film thickness distribution during polishing so that the film thickness distribution of the substrate becomes a target film thickness distribution.

[0155] According to this aspect, by adjusting the pressing force of each first pressing means based on the measurement result of the film thickness distribution during polishing, the film thickness distribution of the substrate can be brought close to the target film thickness distribution, so the film thickness distribution of the substrate can be accurately controlled.

[0156] Furthermore, in the present application, as one embodiment, a calibration method is disclosed, which uses a genetic algorithm to calibrate a top ring having a plurality of piezoelectric elements, prepares a plurality of genetic data, which are arranged data in which data representing the voltage supplied to each piezoelectric element in binary is arranged, actually supplies the voltage corresponding to the plurality of genetic data to the plurality of piezoelectric elements, measures the pressing force based on each piezoelectric element, and calculates the standard deviation of the measured values ​​of the pressing force based on the plurality of piezoelectric elements for each of the genetic data. If the smallest standard deviation among the standard deviations corresponding to the plurality of genetic data is above a prescribed allowable value, performs selection, crossover and / or sudden mutation processing based on the genetic algorithm on the plurality of genetic data to produce new plurality of genetic data, and uses the new plurality of genetic data to repeatedly perform the measurement of the pressing force based on the plurality of piezoelectric elements and the calculation of the standard deviation for each genetic data until the smallest standard deviation among the standard deviations corresponding to the plurality of genetic data is less than the prescribed allowable value. When the smallest standard deviation among the standard deviations corresponding to the plurality of genetic data is less than the prescribed allowable value, selects the genetic data corresponding to the smallest standard deviation as the combination of the voltage supplied to the plurality of piezoelectric elements.

[0157] According to this aspect, the calibration of a plurality of piezoelectric elements can be performed simply and accurately.

[0158] Furthermore, in the present application, as one embodiment, a recording medium is disclosed, storing a program for causing a computer to execute a method for calibrating a top ring having a plurality of piezoelectric elements using a genetic algorithm, preparing a plurality of genetic data, wherein the genetic data is an arrangement of data in which a voltage supplied to each piezoelectric element is arranged in binary, the voltage corresponding to the plurality of genetic data is actually supplied to the plurality of piezoelectric elements, the pressing force based on each piezoelectric element is measured, and for each of the genetic data, the standard deviation of the measured value of the pressing force based on the plurality of piezoelectric elements is calculated, and if the smallest standard deviation among the standard deviations corresponding to the plurality of genetic data is within a prescribed allowable range, If the value of the plurality of genetic data is greater than the specified allowable value, the plurality of genetic data are subjected to selection, crossover and / or sudden mutation based on the genetic algorithm, thereby producing a plurality of new genetic data, and the plurality of new genetic data are used to repeatedly perform the measurement of the pressing force based on the plurality of piezoelectric elements and the calculation of the standard deviation of each genetic data until the minimum standard deviation among the standard deviations corresponding to the plurality of genetic data is less than the specified allowable value, and when the minimum standard deviation among the standard deviations corresponding to the plurality of genetic data is less than the specified allowable value, the genetic data corresponding to the minimum standard deviation is selected as the combination of voltages supplied to the plurality of piezoelectric elements. The recording medium is also referred to as a storage medium or a storage device.

[0159] Explanation of symbols

[0160] 18: top ring shaft (rotational shaft), 300: polishing unit, 302: top ring, 350: polishing table, 351: table shaft, 352: polishing pad, 410: substrate adsorption component, 411: porous component, 411a: substrate adsorption surface, 411b: decompression part, 412: shielding component, 413: frame component, 413A: stopper, 413B: fastening component, 414: suction hole, 415: decompression means, 418: support pad, 419: peripheral band, 420: base component, 421: base body, 421A: stopper, 422: Diaphragm (elastic membrane), 422A: pressurization chamber, 423: suction path, 424: flow path, 425: compressed air supply source, 426: linear guide, 430: piezoelectric element component, 431: retaining body (retaining member), 432: piezoelectric element, 433: fluid bag, 434: pressing force measuring device, 435: driving voltage applying device, 436: power wiring, 437: linear guide, 438: supporting roller, 500: surface pressure distribution measuring device, 501: PC, 900: control device, 1000: substrate processing device, WF: substrate.

Claims

1. A top ring for holding a substrate, characterized in that: have: A base member connected to the rotating shaft; A substrate adsorption component, the substrate adsorption component comprising a porous component having a substrate adsorption surface for adsorbing the substrate and a decompression portion connected to the decompression means; and A first pressurizing component is arranged between the base component and the substrate adsorption component, and has a plurality of first pressurizing means arranged on the side of the substrate adsorption component opposite to the substrate adsorption surface, and each first pressurizing means is constructed to be able to apply pressing force to the substrate adsorption component completely independently of each other.

2. The top ring according to claim 1, characterized in that The first pressurizing assembly further comprises a holding body for holding the plurality of first pressurizing means. The base member further includes a second pressurizing means for pressing a side of the holding body opposite to the plurality of first pressurizing means with a fluid pressure.

3. The top ring according to claim 1 or 2, characterized in that: The first pressurizing assembly further includes a fluid bag with low elasticity, and the fluid bag is provided on the substrate adsorption component side of each pressurizing means.

4. The top ring according to claim 3, characterized in that: The fluid bag holds a liquid.

5. The top ring according to claim 1 or 2, characterized in that: The first pressurizing member is configured to be movable in a vertical direction relative to the base member and the substrate adsorption member.

6. The top ring according to claim 5, characterized in that The base member and the substrate adsorption member are connected by an outer peripheral band, and the outer peripheral band seals the gap between the base member and the substrate adsorption member. The first pressurizing member is sealed in a space surrounded by the base member, the substrate adsorption member, and the peripheral band.

7. The top ring according to claim 5, characterized in that: A linear guide mechanism is provided between an inner side surface of the base component and an outer side surface of the first pressurizing assembly, and the linear guide mechanism guides relative movement between the base component and the first pressurizing assembly.

8. The top ring according to claim 7, characterized in that When viewed from above, the first pressurizing component is a quadrilateral. The linear guide mechanism is disposed only on a pair of opposite outer side surfaces of the first pressurizing assembly.

9. The top ring according to claim 5, characterized in that: The first pressurizing assembly includes a plurality of rollers disposed along the outer circumference of the first pressurizing assembly. The substrate adsorption member is guided by the plurality of rollers to move in a vertical direction relative to the first pressurizing member.

10. The top ring according to claim 1 or 2, characterized in that: The base member has a first stopper, which limits the downward movement of the first pressurizing assembly relative to the base member. The substrate adsorption component has a second stopper that restricts downward movement of the substrate adsorption component relative to the first pressurizing assembly.

11. The top ring according to claim 10, characterized in that: In a plan view, the base component, the substrate adsorption component and the first pressurizing component are quadrilaterals. The first stopper is disposed on the base component corresponding to four corners of the first pressurizing assembly. The second stoppers are provided on the substrate adsorption component corresponding to four corners of the first pressurizing assembly.

12. The top ring according to claim 11, characterized in that A part or the whole of the second stopper is configured to be removable together with the corner of the substrate adsorption component. The substrate adsorption member can be removed from the first pressurizing unit in a state where a part or all of the second stopper is removed together with the corner portion of the substrate adsorption member.

13. The top ring according to claim 1 or 2, characterized in that: The substrate includes a substrate body and a plurality of wiring units arranged on the substrate body. The size of each first pressurizing means corresponds to the size of each wiring unit.

14. The top ring according to claim 1 or 2, characterized in that: The substrate is a quadrilateral substrate.

15. The top ring according to claim 1 or 2, characterized in that: Each first pressurizing means is a piezoelectric element.

16. The top ring according to claim 2, characterized in that: The second pressurizing means is a diaphragm having a pressurizing chamber.

17. A substrate processing device, characterized in that: have: A top ring as claimed in any one of claims 1 to 16; a grinding table holding a grinding pad for pressing the substrate held on the top ring; The decompression means is connected to the porous member; and The first control means controls the pressing force by each first pressurizing means.

18. The substrate processing apparatus according to claim 17, wherein: The first pressurizing assembly further comprises a holding body for holding the plurality of first pressurizing means. The base member further includes a second pressurizing means for pressing a side of the holding body opposite to the plurality of first pressurizing means with a fluid pressure. The substrate processing apparatus further includes a second control means for adjusting a pressing force by the second pressurizing means.

19. The substrate processing apparatus according to claim 17 or 18, wherein: The first control means adjusts the pressing force by each first pressing means based on the measurement result of the film thickness distribution during polishing so that the film thickness distribution of the substrate becomes a target film thickness distribution.

20. A calibration method for calibrating a top ring having a plurality of piezoelectric elements using a genetic algorithm, characterized in that: A plurality of gene data are prepared, the gene data being arrayed data in which data representing the voltage supplied to each piezoelectric element in binary format is arrayed, The voltage corresponding to the plurality of gene data is actually supplied to the plurality of piezoelectric elements, and the pressing force by each piezoelectric element is measured. For each of the gene data, a standard deviation of the measured values ​​of the pressing force of the plurality of piezoelectric elements is calculated, If the smallest standard deviation among the standard deviations corresponding to the plurality of gene data is above a prescribed allowable value, selection, crossover and / or sudden mutation processing based on a genetic algorithm is performed on the plurality of gene data to produce new plurality of gene data, and using the new plurality of gene data, the measurement of the pressing force based on the plurality of piezoelectric elements and the calculation of the standard deviation of each gene data are repeatedly performed until the smallest standard deviation among the standard deviations corresponding to the plurality of gene data is less than the prescribed allowable value. When the smallest standard deviation among the standard deviations corresponding to the plurality of gene data is smaller than the predetermined allowable value, the gene data corresponding to the smallest standard deviation is selected as the combination of voltages supplied to the plurality of piezoelectric elements.

21. A recording medium storing a program for causing a computer to execute a method for calibrating a top ring having a plurality of piezoelectric elements using a genetic algorithm, wherein: A plurality of gene data are prepared, the gene data being arrayed data in which data representing the voltage supplied to each piezoelectric element in binary format is arrayed, The voltage corresponding to the plurality of gene data is actually supplied to the plurality of piezoelectric elements, and the pressing force by each piezoelectric element is measured. For each of the gene data, a standard deviation of the measured values ​​of the pressing force of the plurality of piezoelectric elements is calculated, If the smallest standard deviation among the standard deviations corresponding to the plurality of gene data is above a prescribed allowable value, selection, crossover and / or sudden mutation processing based on a genetic algorithm is performed on the plurality of gene data to produce new plurality of gene data, and using the new plurality of gene data, the measurement of the pressing force based on the plurality of piezoelectric elements and the calculation of the standard deviation of each gene data are repeatedly performed until the smallest standard deviation among the standard deviations corresponding to the plurality of gene data is less than the prescribed allowable value. When the smallest standard deviation among the standard deviations corresponding to the plurality of gene data is smaller than the predetermined allowable value, the gene data corresponding to the smallest standard deviation is selected as the combination of voltages supplied to the plurality of piezoelectric elements.

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