Substrate processing device and substrate processing method

Abstract

To provide a substrate processing device and a substrate processing method which can properly determine a polishing condition for re-polishing, on the basis of a state of a remaining film at a peripheral edge part of a substrate.SOLUTION: A substrate processing device comprises: a polishing part 4 that polishes a peripheral edge part of a substrate W; a remaining-film detecting part 9 that detects a remaining film at the peripheral edge part of the substrate W polished by the polishing part 4; and a control part 20 that determines whether the peripheral edge part of the substrate W needs to be re-polished or not on the basis of a detected result of the remaining film by the remaining-film detecting part 9 and when determining that the peripheral edge part needs to be re-polished, determines a polishing condition for re-polishing, on the basis of the detected result of the remaining film. The polishing part 4 is configured to re-polish the peripheral edge part of the substrate W under the determined polishing condition.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a substrate processing apparatus and a substrate processing method for polishing a substrate such as a wafer.

Background Art

[0002] From the viewpoint of improving the yield in the manufacture of semiconductor devices, the management of the surface state of substrates has recently attracted attention. In the manufacturing process of semiconductor devices, various materials are deposited on a silicon wafer. For this reason, unnecessary films and surface roughness are formed on the peripheral portion of the substrate. In recent years, a method of transporting a substrate while holding only the peripheral portion of the substrate with an arm has become common. Under such circumstances, the unnecessary film remaining on the peripheral portion peels off while going through various processes and adheres to the devices formed on the substrate, resulting in a decrease in yield. Therefore, in order to remove the unnecessary film formed on the peripheral portion of the substrate, the peripheral portion of the substrate is polished using a polishing apparatus.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, the state of the unnecessary film formed on the peripheral portion of the substrate varies from substrate to substrate. For this reason, when polishing the peripheral portion according to a fixed polishing recipe regardless of the state of the film, it may not be possible to completely remove the unnecessary film from the peripheral portion of the substrate. When there is a remaining film because the unnecessary film cannot be removed by polishing, it is necessary to repolish the peripheral portion of the substrate.

[0005] Therefore, the present invention provides a substrate processing apparatus and a substrate processing method capable of appropriately determining the polishing conditions for re-polishing based on the state of the remaining film at the peripheral portion of the substrate.

Means for Solving the Problems

[0006] In one aspect, there is provided a substrate processing apparatus including a polishing unit that polishes a peripheral portion of a substrate, a remaining film detection unit that detects a remaining film at the peripheral portion of the substrate polished by the polishing unit, and a control unit that determines whether re-polishing of the peripheral portion of the substrate is necessary based on a detection result of the remaining film by the remaining film detection unit, and determines polishing conditions for the re-polishing based on the detection result of the remaining film when it is determined that the re-polishing is necessary, wherein the polishing unit is configured to re-polish the peripheral portion of the substrate under the determined polishing conditions. In one aspect, the remaining film detection unit includes an imaging device that generates an image of the peripheral portion of the substrate, and a detection processing unit that detects the remaining film at the peripheral portion of the substrate based on the image. In one aspect, the remaining film detection unit further includes a substrate holding device that holds the substrate and rotates the substrate, and the image is an image of the entire circumference of the peripheral portion of the substrate.

[0007] In one aspect, the detection processing unit is configured to calculate the area of the remaining film from the hue appearing on the image, and the control unit is configured to determine whether re-polishing of the peripheral portion of the substrate is necessary based on a remaining film ratio that is the ratio of the area of the remaining film in the target region to the total area of the target region in the image. In one aspect, the control unit is configured to determine a polishing time as the polishing condition based on the remaining film ratio and correlation data between the remaining film ratio and the polishing time.

[0008] In one aspect, the residual film detection unit is configured to detect the residual film in each of a plurality of regions of the peripheral portion that are arranged in the thickness direction of the substrate, and the control unit determines, based on the detection result of the residual film, whether re-polishing is required in each of the plurality of regions, and as the polishing condition for the re-polishing, is configured to determine a polishing angle corresponding to a region determined to require re-polishing, and the plurality of regions are regions polished at different polishing angles by the polishing unit. In one aspect, the residual film detection unit includes a plurality of imaging devices that respectively generate images of the plurality of regions, and a detection processing unit that detects the residual film in each of the plurality of regions based on the images of the plurality of regions. In one aspect, the residual film detection unit includes an imaging device that generates an image of the peripheral portion of the substrate, and a detection processing unit that detects the residual film of the peripheral portion of the substrate based on the image, and the control unit has a polishing condition determination model constructed by machine learning, inputs the image into the polishing condition determination model, and is configured to output the polishing condition for the re-polishing from the polishing condition determination model.

[0009] There is provided a substrate processing method for detecting a residual film at a peripheral portion of a substrate polished by a polishing unit, determining whether re-polishing of the peripheral portion of the substrate is required based on the detection result of the residual film, determining the polishing condition for the re-polishing based on the detection result of the residual film when it is determined that the re-polishing is necessary, and re-polishing the peripheral portion of the substrate under the determined polishing condition by the polishing unit. In one aspect, detecting the residual film at the peripheral portion of the substrate is generating an image of the peripheral portion of the substrate by an imaging device and detecting the residual film at the peripheral portion of the substrate based on the image. In one aspect, generating the image of the peripheral portion of the substrate is generating an image of the entire circumference of the peripheral portion of the substrate while rotating the substrate by a substrate holding device.

[0010] In one aspect, detecting the remaining film at the peripheral portion of the substrate is to calculate the area of the remaining film from the hue appearing on the image, and determining the necessity of re-polishing at the peripheral portion of the substrate is to determine the necessity of re-polishing at the peripheral portion of the substrate based on the remaining film rate which is the ratio of the area of the remaining film in the target region to the total area of the target region in the image. In one aspect, determining the polishing conditions for the re-polishing is to determine the polishing time as the polishing condition based on the remaining film rate and the correlation data between the remaining film rate and the polishing time.

[0011] In one aspect, detecting the remaining film at the peripheral portion of the substrate is to detect the remaining film in each of a plurality of regions at the peripheral portion arranged in the thickness direction of the substrate, determining the necessity of re-polishing at the peripheral portion of the substrate is to determine the necessity of re-polishing in each of the plurality of regions based on the detection result of the remaining film, and determining the polishing conditions for the re-polishing includes determining the polishing angle corresponding to the region determined to require re-polishing as the polishing condition for the re-polishing, and the plurality of regions are regions polished at different polishing angles by the polishing unit. In one aspect, detecting the remaining film at the peripheral portion of the substrate is to generate an image of the peripheral portion of the substrate by an imaging device and detect the remaining film at the peripheral portion of the substrate based on the image, and determining the polishing conditions for the re-polishing is to input the image into a polishing condition determination model constructed by machine learning and output the polishing conditions for the re-polishing from the polishing condition determination model.

Advantages of the Invention

[0012] The control unit determines the necessity of re-polishing based on the detection result of the remaining film at the peripheral portion of the substrate, and when it is determined that re-polishing is necessary, determines the polishing conditions for the re-polishing based on the detection result of the remaining film at the peripheral portion of the substrate. Therefore, it is possible to determine the polishing conditions for the re-polishing suitable for the state of the remaining film at the peripheral portion of the substrate.

Brief Description of the Drawings

[0013]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Figure 13

Figure 14

Embodiments for Carrying Out the Invention

[0014] Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a plan view showing an embodiment of a substrate processing apparatus. The substrate processing apparatus includes a housing 1, a load port 2, a polishing unit 4 having two polishing modules 4A and 4B, a cleaning unit 6, a drying unit 7, a residual film detection unit 9, a first temporary stage 11, a second temporary stage 12, a first transfer robot 14, a second transfer robot 15, a third transfer robot 16, a fourth transfer robot 17, and a control unit 20. The polishing modules 4A and 4B, the cleaning unit 6, the drying unit 7, the residual film detection unit 9, the first temporary stage 11, the second temporary stage 12, the first transfer robot 14, the second transfer robot 15, the third transfer robot 16, the fourth transfer robot 17, and the control unit 20 are arranged inside the housing 1.

[0015] A substrate to be polished such as a wafer is accommodated in a substrate cassette 19, and the substrate cassette 19 is placed on the load port 2. The first transfer robot 14 is arranged adjacent to the load port 2. The first transfer robot 14 takes out the substrate to be polished from the substrate cassette 19 on the load port 2 and places it on the first temporary stage 11. The first temporary stage 11 is a temporary stage for temporarily placing the substrate before the substrate is polished by the polishing modules 4A and 4B.

[0016] The polishing unit 4 including two polishing modules 4A and 4B is configured to polish the peripheral portion of a substrate such as a wafer. In the present embodiment, the polishing unit 4 includes two polishing modules 4A and 4B, but in one embodiment, the polishing unit 4 may include one polishing module or three or more polishing modules. In the present embodiment, the peripheral portion of the substrate is polished by at least one of the polishing module 4A and the polishing module 4B.

[0017] The second transfer robot 15 is arranged adjacent to the polishing module 4A and the polishing module 4B. The second transfer robot 15 transfers the substrate placed on the first temporary stage 11 to the polishing module 4A or the polishing module 4B. Further, the second transfer robot 15 takes out the substrate from the polishing module 4A or the polishing module 4B and places it on the second temporary stage 12. The second temporary stage 12 is a temporary stage for temporarily placing the substrate before the substrate polished by the polishing module 4A or the polishing module 4B is cleaned by the cleaning unit 6.

[0018] The third transfer robot 16 is arranged adjacent to the cleaning unit 6. The third transfer robot 16 transfers the substrate placed on the second temporary stage 12 to the cleaning unit 6. The cleaning unit 6 of the present embodiment is configured to clean the substrate with a roll-shaped sponge member. In one embodiment, the cleaning unit 6 may be configured to clean the substrate with a pencil-shaped sponge member. In other embodiments, the substrate processing apparatus may include a cleaning unit that cleans the substrate with a pencil-shaped sponge member in addition to the cleaning unit 6 that cleans the substrate with a roll-shaped sponge member.

[0019] The fourth transfer robot 17 is arranged between the cleaning unit 6 and the drying unit 7. The fourth transfer robot 17 takes out the substrate from the cleaning unit 6 and transfers it to the drying unit 7. The drying unit 7 is configured to dry the substrate cleaned by the cleaning unit 6. The first transfer robot 14 transfers the substrate between the drying unit 7 and the residual film detection unit 9. The substrate dried by the drying unit 7 is transferred to the residual film detection unit 9 by the first transfer robot 14.

[0020] The residual film detection unit 9 is configured to detect the residual film at the peripheral edge of the substrate polished by the polishing module 4A and / or the polishing module 4B, cleaned by the cleaning unit 5, and dried by the drying unit 7. As will be described in detail later, the control unit 20 is configured to determine whether re-polishing of the peripheral edge of the substrate is necessary based on the detection result of the residual film by the residual film detection unit 9.

[0021] When the control unit 20 determines that the peripheral edge of the substrate needs to be re-polished, the first transfer robot 14 takes out the substrate from the residual film detection unit 9 and transfers the substrate to the polishing module 4A or the polishing module 4B. The polishing module 4A or the polishing module 4B re-polishes the peripheral edge of the substrate. When the control unit 20 determines that the re-polishing of the peripheral edge of the substrate is unnecessary, the first transfer robot 14 takes out the substrate from the residual film detection unit 9 and returns it to the substrate cassette 19 of the load port 2.

[0022] The polishing unit 4 (including the polishing module 4A and the polishing module 4B), the cleaning unit 6, the drying unit 7, the residual film detection unit 9, the first transfer robot 14, the second transfer robot 15, the third transfer robot 16, and the fourth transfer robot 17 are electrically connected to the control unit 20. The operations of the polishing unit 4, the cleaning unit 6, the drying unit 7, the residual film detection unit 9, the first transfer robot 14, the second transfer robot 15, the third transfer robot 16, and the fourth transfer robot 17 are controlled by the control unit 20.

[0023] The control unit 20 includes at least one computer. The control unit 20 includes a storage device 20a in which a program and the like are stored, and an arithmetic device 20b that executes arithmetic operations according to instructions included in the program. The storage device 20a includes a main storage device such as a random access memory (RAM), and an auxiliary storage device such as a hard disk drive (HDD) and a solid state drive (SSD). Examples of the arithmetic device 20b include a CPU (central processing unit) and a GPU (graphics processing unit). However, the specific configuration of the control unit 20 is not limited to these examples.

[0024] Next, the details of the polishing modules 4A and 4B of the polishing unit 4 will be described. The polishing modules 4A and 4B are configured to polish the peripheral edge of the substrate W. FIGS. 2(a) and 2(b) are enlarged cross-sectional views showing the peripheral edge of the substrate W. More specifically, FIG. 2(a) is a cross-sectional view of a so-called straight-type substrate, and FIG. 2(b) is a cross-sectional view of a so-called round-type substrate. The bevel portion B has a chamfered shape or a rounded shape.

[0025] In the substrate W of FIG. 2(a), the bevel portion B is the outermost peripheral surface of the substrate W composed of an upper inclined surface (upper bevel portion) B1, a lower inclined surface (lower bevel portion) B2, and a side portion (apex) B3. In the substrate W of FIG. 2(b), the bevel portion B is a portion having a curved cross section that constitutes the outermost peripheral surface of the substrate W. The top edge portion E1 is an annular flat portion located radially inward of the bevel portion B. The bottom edge portion E2 is located on the side opposite to the top edge portion E1 and is an annular flat portion located radially inward of the bevel portion B. The top edge portion E1 may include the region where the device is formed. In this specification, the peripheral edge portion of the substrate W refers to a region including at least one of the top edge portion E1, the bevel portion B, and the bottom edge portion E2.

[0026] FIG. 3 is a plan view showing an embodiment of the polishing module 4A, and FIG. 4 is a side view of the polishing module 4A shown in FIG. 3. Since the polishing module 4A and the polishing module 4B basically have the same configuration, the polishing module 4A will be described below. The polishing module 4A includes a substrate holding portion 25, four polishing heads 30A to 30D, four polishing tape supply mechanisms 40A to 40D, a lower supply nozzle 51, and an upper supply nozzle 52. In FIG. 4, the illustration of the polishing heads 30B and 30C is omitted.

[0027] The substrate holding portion 25 includes a holding stage 27 that holds the substrate W by vacuum suction, a shaft 28 connected to the central portion of the holding stage 27, and a holding stage drive mechanism 29 that rotates and moves the holding stage 27 up and down. The shaft 28 of the substrate holding portion 25 extends through the base plate 68, and the holding stage drive mechanism 29 is disposed below the base plate 68. The holding stage drive mechanism 29 is configured to rotate the holding stage 27 about the rotation axis Cr and move it in the vertical direction along the rotation axis Cr. The axis passing through the center O1 of the substrate W and the rotation axis Cr of the holding stage 27 coincide.

[0028] The grinding module 4A is provided with at least one grinding head for grinding the peripheral portion of the substrate W. In the present embodiment, as shown in FIG. 3, four grinding heads 30A, 30B, 30C, and 30D are arranged on the outer side in the radial direction of the substrate W held by the substrate holding portion 25. In the present embodiment, four grinding tape supply mechanisms 40A, 40B, 40C, and 40D are respectively provided on the outer side in the radial direction of the four grinding heads 30A, 30B, 30C, and 30D. In one embodiment, the number of grinding heads and the number of corresponding grinding tape supply mechanisms may be three or less, or five or more.

[0029] As shown in FIG. 3, the grinding head 30A and the grinding head 30D are symmetrically arranged with respect to a line Lc passing through the center O1 of the substrate W and perpendicular to the rotation axis Cr. The grinding head 10B and the grinding head 10C are symmetrically arranged with respect to the line Lc. However, the arrangement of the first grinding head 10A, the second grinding head 10B, the third grinding head 10C, and the fourth grinding head 10D is not limited to this embodiment.

[0030] The grinding head 30A is configured to press the grinding tape 22A supplied from the grinding tape supply mechanism 40A against the peripheral portion of the substrate W to grind the peripheral portion of the substrate W. The grinding head 30B is configured to press the grinding tape 22B supplied from the grinding tape supply mechanism 40B against the peripheral portion of the substrate W to grind the peripheral portion of the substrate W. The grinding head 30C is configured to press the grinding tape 22C supplied from the grinding tape supply mechanism 40C against the peripheral portion of the substrate W to grind the peripheral portion of the substrate W. The grinding head 30D is configured to press the grinding tape 22D supplied from the grinding tape supply mechanism 40D against the peripheral portion of the substrate W to grind the peripheral portion of the substrate W.

[0031] The grinding heads 30A, 30B, 30C, and 30D basically have the same configuration, and the grinding tape supply mechanisms 40A, 40B, 40C, and 40D also basically have the same configuration. Hereinafter, the grinding head 30A and the grinding tape supply mechanism 40A will be described.

[0032] As shown in FIG. 4, the polishing head 30A includes a pressing member 32 that presses the polishing surface of the polishing tape 22A against the peripheral portion of the substrate W, and an air cylinder 35 as an actuator that moves the pressing member 32 toward the peripheral portion of the substrate W. By controlling the air pressure supplied to the air cylinder 35, the pressing force of the polishing tape 22A against the substrate W is adjusted. The pressing member 32 is disposed on the back side of the polishing tape 22A (the side opposite to the polishing surface having abrasive grains). When the pressing member 32 is moved toward the substrate W by the air cylinder 35, the pressing member 32 presses the polishing tape 22A against the peripheral portion of the substrate W from its back side. Thereby, the polishing head 30A polishes the peripheral portion of the substrate W with the polishing tape 22A.

[0033] The polishing tape supply mechanism 40A is configured to supply the polishing tape 22A to the polishing head 30A and recover it from the polishing head 30A. The polishing tape supply mechanism 40A includes a tape unwinding reel 41, a tape winding reel 42, and a plurality of guide rollers 44, 45, 46, 47. The tape unwinding reel 41, the tape winding reel 42, and the plurality of guide rollers 44, 45, 46, 47 are fixed to a reel base 48. The polishing tape 22A is supplied to the polishing head 30A such that the polishing surface of the polishing tape 22A faces the peripheral portion of the substrate W. The traveling direction of the polishing tape 22A is guided by the guide rollers 44, 45, 46, 47. The polishing tape 22A supplied to the polishing head 30A is fed at a predetermined speed by a tape feed mechanism 36 provided in the polishing head 30A.

[0034] Tension motors (not shown) are respectively connected to the tape unwinding reel 41 and the tape winding reel 42. The tape unwinding reel 41 and the tape winding reel 42 are fixed to the reel base 48 via the tension motors. Each tension motor is configured to apply a predetermined torque to the tape unwinding reel 41 and the tape winding reel 42 so as to apply a predetermined tension to the polishing tape 22A.

[0035] The lower supply nozzle 51 is configured to supply liquid to the lower surface of the substrate W. The upper supply nozzle 52 is configured to supply liquid to the upper surface of the substrate W. An example of the liquid supplied to the substrate W from the lower supply nozzle 51 and the upper supply nozzle 52 is pure water. During polishing of the substrate W, liquid is supplied from the lower supply nozzle 51 to the lower surface of the substrate W and liquid is supplied from the upper supply nozzle 52 to the upper surface of the substrate W.

[0036] The polishing module 4A further includes four polishing head translation mechanisms 60 that translate the polishing heads 30A, 30B, 30C, and 30D along the radial direction of the substrate W, respectively. Each of the polishing head translation mechanisms 60 includes a connecting member 63, a guide rail 64, a connecting shaft 66, and an air cylinder 67 as an actuator. Since the four polishing head translation mechanisms 60 basically have the same configuration, hereinafter, the polishing head translation mechanism 60 that translates the polishing head 30A will be described.

[0037] The polishing head translation mechanism 60 is connected to the polishing head 30A via a movable plate 61. More specifically, a polishing head support member 38 connected to the polishing head 30A is fixed to the upper surface of the movable plate 61, and the polishing head translation mechanism 60 is connected to the lower surface of the movable plate 61. The polishing head 30A can move integrally with the movable plate 61.

[0038] The guide rail 64 extends in the radial direction of the holding stage 27 and is fixed to the upper surface of the base plate 68. The air cylinder 67 is connected to the movable plate 61 via the connecting member 63 and the connecting shaft 66 and is fixed to the upper surface of the base plate 68. The polishing head translation mechanism 60 can move the polishing head 30A in a direction approaching the rotation axis Cr of the substrate W (i.e., the center O1 of the substrate W) and in a direction away from the rotation axis Cr (i.e., the center O1 of the substrate W) at a predetermined moving speed by driving the air cylinder 67 to move the movable plate 61 along the guide rail 64.

[0039] In addition, if the polishing head 30A can be moved in a direction approaching the rotation axis Cr of the substrate W (i.e., the center O1 of the substrate W) and in a direction away from the rotation axis Cr (i.e., the center O1 of the substrate W), the specific configuration of the polishing head translation mechanism 60 is not limited to this embodiment.

[0040] As shown in FIG. 3, the polishing module 4A further includes four polishing head tilting mechanisms 70A, 70B, 70C, and 70D that tilt the polishing heads 30A, 30B, 30C, and 30D with respect to the substrate holding surface of the holding stage 27, respectively. The polishing head tilting mechanism 70A is connected to the polishing head 30A, the polishing head tilting mechanism 70B is connected to the polishing head 30B, the polishing head tilting mechanism 70C is connected to the polishing head 30C, and the polishing head tilting mechanism 70D is connected to the polishing head 30D. Since the four polishing head tilting mechanisms 70A to 70D basically have the same configuration, the polishing head tilting mechanism 70A will be described below.

[0041] The polishing head tilting mechanism 70A includes a crank arm 72 connected to the polishing head 30A and an arm rotating device 73 that rotates the crank arm 72. One end of the crank arm 72 is located at the same height as the substrate holding surface of the holding stage 27 and is connected to the arm rotating device 73. The other end of the crank arm 72 is connected to the polishing head 30A. The arm rotating device 73 is disposed inside the polishing head support member 38.

[0042] When the arm rotating device 73 rotates the crank arm 72, the polishing head tilting mechanism 70A can tilt the entire polishing head 30A with respect to the substrate W on the substrate holding surface of the holding stage 27 at a predetermined tilting speed. Further, the polishing head tilting mechanism 70A is configured to be able to maintain the polishing head 30A at a predetermined tilting angle. In addition, if the polishing head 30A can be tilted with respect to the substrate holding surface of the holding stage 27 and the substrate W, the specific configuration of the polishing head tilting mechanism 70A is not limited to this embodiment.

[0043] FIG. 5 is a view showing a state in which the polishing head 30A is polishing the bevel portion B of the substrate W. As shown in FIG. 5, while continuously changing the inclination angle of the polishing head 30A by the polishing head tilting mechanism 70A (see FIG. 3), the polishing head 30A can polish the bevel portion B of the substrate W. Alternatively, with the inclination angle of the polishing head 30A fixed by the polishing head tilting mechanism 70A, the polishing head 30A can polish a specific region of the bevel portion B of the substrate W (for example, the upper inclined surface (upper bevel portion) B1, the lower inclined surface (lower bevel portion) B2, and the side portion (apex) B3 described with reference to FIG. 2(a)). For example, by tilting the polishing head 30A so that the polishing angle corresponding to the upper inclined surface (upper bevel portion) B1 is obtained by the polishing head tilting mechanism 70A, the polishing head 30A can polish the upper inclined surface (upper bevel portion) B1.

[0044] Similarly, while the polishing head tilting mechanisms 70B, 70C, 70D continuously change the inclination angles of the polishing heads 30B, 30C, 30D, respectively, or with the inclination angles of the polishing heads 30B, 30C, 30D fixed by the polishing head tilting mechanisms 70B, 70C, 70D, respectively, the polishing heads 30B, 30C, 30D can polish the bevel portion B of the substrate W.

[0045] FIG. 6 is a view showing a state in which the polishing head 30A is polishing the top edge portion E1 of the substrate W, and FIG. 7 is a view showing a state in which the polishing head 30A is polishing the bottom edge portion E2 of the substrate W. As shown in FIG. 6, by tilting the pressing member 32 of the polishing head 30A so as to face the top edge portion E1 of the substrate W by the polishing head tilting mechanism 70A (see FIG. 3), the polishing head 30A can polish the top edge portion E1 of the substrate W. Further, as shown in FIG. 7, by tilting the pressing member 32 of the polishing head 30A so as to face the bottom edge portion E2 of the substrate W by the polishing head tilting mechanism 70A (see FIG. 3), the polishing head 30A can polish the bottom edge portion E2 of the substrate W.

[0046] Similarly, the polishing head tilting mechanisms 70B, 70C, and 70D tilt the polishing heads 30B, 30C, and 30D respectively so as to face the top edge portion E1 and the bottom edge portion E2 of the substrate W, and the polishing heads 30B, 30C, and 30D can polish the top edge portion E1 and the bottom edge portion E2 of the substrate W. Thus, the polishing heads 30A to 30D can polish a plurality of regions (i.e., the bevel portion B, the top edge portion E1, and the bottom edge portion E2) of the peripheral portion of the substrate W.

[0047] The polishing heads 30A to 30D can polish the peripheral portion of the substrate W simultaneously. For example, in order to improve the polishing rate, the entire peripheral portion of the substrate W including the top edge portion E1, the bevel portion B, and the bottom edge portion E2 can be polished by the polishing head 30A, and at the same time, the entire peripheral portion of the substrate W including the top edge portion E1, the bevel portion B2, and the bottom edge portion E2 can be polished by the polishing head 30B. Alternatively, the top edge portion E1 can be polished by the polishing head 30A, the bevel portion B can be polished by the polishing head 30B, and the bottom edge portion E2 can be polished by the polishing head 30C.

[0048] The polishing tapes 22A to 22D may be different types of polishing tapes. For example, a polishing tape for rough polishing (i.e., a polishing tape having relatively large abrasive grains) may be used as the polishing tape 22A, and polishing tapes for finish polishing (i.e., polishing tapes having relatively small abrasive grains) may be used as the polishing tapes 22B to 22D. In this case, the entire peripheral portion of the substrate W including the top edge portion E1, the bevel portion B, and the bottom edge portion E2 can be rough polished by the polishing head 30A, and then the entire peripheral portion of the substrate W including the top edge portion E1 polished by the polishing head 30B, the bevel portion B polished by the polishing head 30C, and the bottom edge portion E2 polished by the polishing head 30D can be finish polished.

[0049] The substrate holding unit 25, the polishing heads 30A to 30D, the polishing tape supply mechanisms 40A to 40D, the lower supply nozzle 51, the upper supply nozzle 52, the polishing head translation mechanism 60, and the polishing head tilting mechanisms 70A to 70D are electrically connected to the control unit 20 (see FIG. 1). The operations of the substrate holding unit 25, the polishing heads 30A to 30D, the polishing tape supply mechanisms 40A to 40D, the lower supply nozzle 51, the upper supply nozzle 52, the polishing head translation mechanism 60, and the polishing head tilting mechanisms 70A to 70D are controlled by the control unit 20.

[0050] The polishing of the peripheral portion of the substrate W is performed as follows. Hereinafter, the case of polishing the peripheral portion of the substrate W with the polishing head 30A of the polishing module 4A will be described. When the substrate W is transported to the polishing module 4A, the control unit 20 issues a command to the holding stage drive mechanism 29 of the substrate holding unit 25 to raise the holding stage 27. The substrate W is placed on the substrate holding surface of the holding stage 27 and held on the holding stage 27 by vacuum suction. The control unit 20 issues a command to the holding stage drive mechanism 29 of the substrate holding unit 25 to lower the substrate W to the polishing position and rotate the holding stage 27 and the substrate W. Further, the control unit 20 issues a command to the lower supply nozzle 51 and the upper supply nozzle 52 to supply liquid from the lower supply nozzle 51 and the upper supply nozzle 52.

[0051] Next, the control unit 20 issues a command to the polishing tape supply mechanism 40A to start supplying the polishing tape 22A to the polishing head 30A. When polishing the top edge portion E1 of the substrate W, the control unit 20 issues a command to the polishing head tilting mechanism 70A to tilt the polishing head 30A so as to obtain a polishing angle corresponding to the top edge portion E1. Thereafter, a command is issued to the polishing head translation mechanism 60 to move the polishing head 30A. The control unit 20 issues a command to the air cylinder 35 of the polishing head 30A to press the polishing tape 22A against the top edge portion E1 of the substrate W with the pressing member 32 of the polishing head 30A to polish the top edge portion E1. The same applies when polishing the bottom edge portion E2 of the substrate W.

[0052] When continuously polishing the bevel portion B of the substrate W, the control unit 20 issues a command to the polishing head tilting mechanism 70A to tilt the polishing head 30A to a polishing angle corresponding to the portion where the polishing of the bevel portion B starts. Thereafter, the control unit 20 issues a command to the air cylinder 35 of the polishing head 30A, and tilts the polishing head 30A within a predetermined angle range with the pressing member 32 of the polishing head 30A pressing the polishing tape 22A against the peripheral portion of the substrate W.

[0053] When polishing a specific region (for example, the upper bevel portion B1) of the bevel portion B of the substrate W, the control unit 20 issues a command to the polishing head tilting mechanism 70A to tilt the polishing head 30A to a polishing angle corresponding to the specific region (for example, the upper bevel portion B1) of the bevel portion B. Thereafter, the control unit 20 issues a command to the air cylinder 35 of the polishing head 30A, and presses the polishing tape 22A against the specific region of the substrate W with the pressing member 32 of the polishing head 30A.

[0054] After the peripheral portion of the substrate W has been polished according to a predetermined polishing recipe, the control unit 20 issues commands to the respective components of the polishing module 4A to terminate the polishing of the substrate W. Specifically, the control unit 20 stops the operation of the polishing head translational movement mechanism 60 or the polishing head tilting mechanism 70A, stops the drive of the air cylinder 35 of the polishing head 30A, and separates the pressing member 32 of the polishing head 30A from the substrate W. Thereafter, the control unit 20 stops the operations of the substrate holding unit 25, the polishing tape supply mechanism 40A, the polishing tape supply mechanism 40B, the lower supply nozzle 51, and the upper supply nozzle 52 to terminate the polishing of the substrate W.

[0055] Next, the details of the residual film detection unit 9 will be described. FIG. 8 is a schematic diagram showing an embodiment of the residual film detection unit 9. Unnecessary films may not be removed by polishing the peripheral portions of the substrate W by the polishing modules 4A and 4B, and residual films may exist at the peripheral portions of the substrate W. The residual film detection unit 9 is configured to detect the residual films at the peripheral portions of the substrate W polished by the polishing modules 4A and 4B. As shown in FIG. 8, the residual film detection unit 9 of the present embodiment includes a substrate holding device 80 that holds and rotates the substrate W, at least one imaging device (in this embodiment, five imaging devices 86A, 86B, 86C, 86D, and 86E) that generates an image of the peripheral portion of the substrate W, and a detection processing unit 87 that detects the residual films at the peripheral portions of the substrate W based on the images generated by the imaging devices 86A to 86E.

[0056] The substrate holding device 80 includes a holding stage 82 that holds the substrate W by vacuum suction, a shaft 83 connected to the central portion of the holding stage 82, and a holding stage rotation mechanism 84 that rotates the holding stage 82. The holding stage rotation mechanism 84 is configured to rotate the holding stage 82 about the axis of the shaft 83.

[0057] FIG. 9 is an enlarged schematic diagram of the imaging devices 86A to 86E shown in FIG. 8. The five imaging devices 86A to 86E are configured to generate images of a plurality of (in this embodiment, five) regions of the peripheral portion of the substrate W arranged in the thickness direction of the substrate W. In this embodiment, the substrate W is a straight type substrate described with reference to FIG. 2(a), and the plurality of regions of the peripheral portion of the substrate W are a top edge portion E1, an upper inclined surface (upper bevel portion) B1, a side portion (apex) B3, a lower inclined surface (lower bevel portion) B2, and a bottom edge portion E2. The plurality of regions of the peripheral portion of the substrate W are regions polished at different polishing angles by the polishing modules 4A and 4B of the polishing unit 4.

[0058] The imaging device 86A is arranged facing the top edge portion E1 of the substrate W, and is configured to generate an image including the top edge portion E1 of the substrate W. The imaging device 86B is arranged facing the upper inclined surface (upper bevel portion) B1 of the substrate W, and is configured to generate an image including the upper inclined surface (upper bevel portion) B1 of the substrate W. The imaging device 86C is arranged facing the side portion (apex) B3 of the substrate W, and is configured to generate an image including the side portion (apex) B3 of the substrate W. The imaging device 86D is arranged facing the lower inclined surface (lower bevel portion) B2 of the substrate W, and is configured to generate an image including the lower inclined surface (lower bevel portion) B2 of the substrate W. The imaging device 86E is arranged facing the bottom edge portion E2 of the substrate W, and is configured to generate an image including the bottom edge portion E2 of the substrate W.

[0059] Examples of the imaging devices 86A to 86E include cameras equipped with image sensors such as CCD sensors and CMOS sensors. In the present embodiment, the imaging devices 86A to 86E are configured to generate color images of the peripheral portion of the substrate W. In one embodiment, the imaging devices 86A to 86E may be configured to generate grayscale images of the peripheral portion of the substrate W.

[0060] In the present embodiment, the residual film detection unit 9 includes five imaging devices 86A to 86E, but the number of imaging devices is not particularly limited to this embodiment. For example, the residual film detection unit 9 may include a single imaging device and may be configured to generate an image of a part or all of the region of the peripheral portion of the substrate W by the single imaging device.

[0061] In the present embodiment, the substrate holding device 80 and the imaging devices 86A to 86E are electrically connected to the detection processing unit 87, and the operations of the substrate holding device 80 and the imaging devices 86A to 86E are controlled by the detection processing unit 87. In one embodiment, the substrate holding device 80 and the imaging devices 86A to 86E may be electrically connected to the control unit 20, and the operations of the substrate holding device 80 and the imaging devices 86A to 86E may be controlled by the control unit 20.

[0062] The detection processing unit 87 includes at least one computer. The detection processing unit 87 includes a storage device 87a in which programs and the like are stored, and an arithmetic device 87b that executes arithmetic operations according to instructions included in the programs. The storage device 87a includes a main storage device such as a random access memory (RAM), and auxiliary storage devices such as a hard disk drive (HDD) and a solid state drive (SSD). Examples of the arithmetic device 87b include a CPU (central processing unit) and a GPU (graphics processing unit). However, the specific configuration of the detection processing unit 87 is not limited to these examples. In one embodiment, the detection processing unit 87 may be integrally configured with the control unit 20.

[0063] The detection processing unit 87 gives commands to the holding stage rotation mechanism 84 of the substrate holding device 80 to rotate the holding stage 82 and the substrate W, and causes the imaging devices 86A to 86E to generate images of the peripheral portion of the substrate W each time the substrate W rotates by a predetermined angle. The detection processing unit 87 acquires images of the entire circumference of the peripheral portion of the substrate W generated by the imaging devices 86A to 86E while the substrate W makes one rotation. The images of the entire circumference of the peripheral portion of the substrate W are a plurality of images of the peripheral portion of the substrate W arranged in the circumferential direction of the substrate W. For example, the detection processing unit 87 gives commands to the imaging devices 86A to 86E to generate images of the peripheral portion of the substrate W each time the substrate W rotates by 1.5°. Each of the imaging devices 86A to 86E generates 240 (360°÷1.5° = 240) images of the entire circumference of the corresponding region of the peripheral portion of the substrate W arranged in the circumferential direction of the substrate W while the substrate W makes one rotation.

[0064] FIG. 10 is a diagram showing an example of images Pa, Pb, Pc, Pd, and Pe of a plurality of regions at the peripheral portion of substrate W, which are respectively generated by imaging devices 86A, 86B, 86C, 86D, and 86E. The images Pa to Pe shown in FIG. 10 are images generated by the imaging devices 86A to 86E in a single imaging. Image Pa is an image including the top edge portion E1 of substrate W generated by imaging device 86A. Image Pb is an image including the upper inclined surface (upper bevel portion) B1 of substrate W generated by imaging device 86B. Image Pc is an image including the side portion (apex) B3 of substrate W generated by imaging device 86C. Image Pd is an image including the lower inclined surface (lower bevel portion) B2 of substrate W generated by imaging device 86D. Image Pe is an image including the bottom edge portion E2 of substrate W generated by imaging device 86E.

[0065] Portions of substrate W with different inclinations appear with different hues in the image. In the images shown in FIG. 10, for example, image Pa includes the top edge portion E1 and a part of the upper inclined surface (upper bevel portion) B1, and the top edge portion E1 and the upper inclined surface (upper bevel portion) B1 appear with different hues. Image Pe includes the bottom edge portion E2 and a part of the lower inclined surface (lower bevel portion) B2, and the lower inclined surface (lower bevel portion) B2 and the bottom edge portion E2 appear with different hues.

[0066] Furthermore, the portion S where the unnecessary film has been removed by the polishing modules 4A and 4B (i.e., the portion where no remaining film exists) and the portion R where the remaining film exists appear with different hues in the image. In the example shown in FIG. 10, the remaining film exists in the portion R indicated by the hatching in images Pa, Pb, and Pe.

[0067] The detection processing unit 87 sets target regions Ta, Tb, Tc, Td, and Te in the images Pa, Pb, Pc, Pd, and Pe, respectively. In the example shown in FIG. 10, the target regions Ta to Te are the ranges surrounded by thick lines. The target regions Ta to Te are preset so as to exclude portions other than the substrate W and overlapping portions in a plurality of images (for example, the upper bevel portion B1 of the image Pa and the lower bevel portion B2 of the image Pe) from the corresponding images. The setting ranges of the target regions Ta to Te are stored in advance in the storage device 87a of the detection processing unit 87.

[0068] By appropriately setting the target regions in each image, a plurality of images generated by a plurality of imaging devices can be made to correspond to different regions of the peripheral portion of the substrate W. In the example shown in FIG. 10, the target region Ta corresponds to the top edge portion E1 of the substrate W, the target region Tb corresponds to the upper bevel portion B1 of the substrate W, the target region Tc corresponds to the side portion (apex) B3 of the substrate W, the target region Td corresponds to the lower bevel portion B2 of the substrate W, and the target region Te corresponds to the bottom edge portion E2 of the substrate W. Therefore, the detection processing unit 87 can detect the residual films in each of the top edge portion E1, the upper bevel portion B1, the side portion (apex) B3, the lower bevel portion B2, and the bottom edge portion E2, which are a plurality of regions of the peripheral portion of the substrate W, from the hues appearing in each of the target regions Ta to Te.

[0069] FIG. 11 is a diagram showing an example of an image of the entire circumference of the peripheral portion of the substrate W. Hereinafter, as an example of an image of the entire circumference of the peripheral portion of the substrate W, an image of the entire circumference of the top edge portion E1 of the substrate W generated by the imaging device 86A will be described, but the same applies to images of the entire circumference of other regions of the peripheral portion of the substrate W generated by the imaging devices 86B to 86E.

[0070] In the example shown in FIG. 11, the images of the entire circumference of the top edge portion E1 of the substrate W are Z images arranged in the circumferential direction of the substrate W. The images Pa-1 to Pa-Z constitute the images of the entire circumference of the top edge portion E1 of the substrate W generated by the imaging device 86A. More specifically, the image Pa-1 shown in FIG. 11 is the first image of the top edge portion E1 of the substrate W generated by the imaging device 86A, the image Pa-2 is the second image of the top edge portion E1 of the substrate W generated by the imaging device 86A, the image Pa-3 is the third image of the top edge portion E1 of the substrate W generated by the imaging device 86A, and the image Pa-Z is the Z-th image of the top edge portion E1 of the substrate W generated by the imaging device 86A. In one embodiment, the detection processing unit 87 may integrate these images to generate one image.

[0071] The detection processing unit 87 is configured to detect the residual film R from the hue appearing in the target region within the image of the peripheral edge portion of the substrate W. In the example shown in FIG. 11, the detection processing unit 87 detects the residual film R from the hue appearing in the target region Ta within the images Pa-1 to Pa-Z. Specifically, the detection processing unit 87 acquires the hue values indicating the respective hues of the plurality of pixels constituting each image. The detection processing unit 87 compares the hue values of the plurality of pixels constituting each image with a predetermined hue reference value to detect the residual film R. For example, the detection processing unit 87 detects the residual film R in the pixel when the hue value of the pixel is larger than the hue reference value. The hue reference value is predetermined based on experimental results or the like and is stored in the storage device 87a of the detection processing unit 87.

[0072] In the present embodiment, the detection processing unit 87 is configured to calculate the area of the residual film R within the target region from the hue appearing in the target region within the image of the peripheral edge portion of the substrate W. The area can be represented by the number of pixels. In the example shown in FIG. 11, the detection processing unit 87 calculates the number of pixels N1 to NZ, which are the areas of the residual film R (detected) existing within the target region Ta within the images Pa-1 to Pa-Z.

[0073] In one embodiment, the detection processing unit 87 may be configured to determine the thickness of the remaining film R in the target region from the hue appearing in the target region within the image of the peripheral portion of the substrate W. The hue on the image changes depending on the thickness of the remaining film R. The detection processing unit 87 may determine the thickness of the remaining film R in the target region from the hue appearing in the target region based on the correlation data between the hue on the image acquired in advance and the thickness of the remaining film R. In this case, the correlation data between the hue on the image and the thickness of the remaining film R is acquired in advance based on experimental results or the like and stored in the storage device 87a of the detection processing unit 87.

[0074] Furthermore, the detection processing unit 87 may determine the thickness of the remaining film R for each pixel constituting the image. The detection processing unit 87 may determine the thickness of the remaining film R for each pixel within the target region in the image and calculate the average value of the thicknesses of the remaining film R existing within the target region.

[0075] In another embodiment, the remaining film detection unit 9 may be a film thickness measurement device (for example, an optical film thickness measurement device) that measures the thickness of the remaining film existing at the peripheral portion of the substrate W. In this case, the remaining film detection unit 9 directly measures the thickness of the remaining film existing at the peripheral portion of the substrate W without generating an image of the peripheral portion of the substrate W by the imaging device, and detects the remaining film existing at the peripheral portion of the substrate W.

[0076] The remaining film detection unit 9 of the present embodiment is configured to detect the remaining film at each of the top edge portion E1, upper bevel portion B1, side portion (apex) B3, lower bevel portion B2, and bottom edge portion E2 of the peripheral portion of the substrate W arranged in the thickness direction of the substrate W. Therefore, the detection result of the remaining film by the remaining film detection unit 9 includes the detection results of the remaining film at each of the top edge portion E1, upper bevel portion B1, side portion B3, lower bevel portion B2, and bottom edge portion E2 of the peripheral portion of the substrate W.

[0077] The residual film detection unit 9 (specifically, the detection processing unit 87) is electrically connected to the control unit 20. The detection result of the residual film at the peripheral edge of the substrate W by the residual film detection unit 9 (specifically, the detection processing unit 87) is sent to the control unit 20. In the example shown in FIG. 11, as the detection result of the residual film R at the top edge portion E1 of the substrate W, the number of pixels N1 to NZ of the residual film R in the target region Ta within the images Pa-1 to Pa-Z is sent to the control unit 20.

[0078] The control unit 20 is configured to determine whether re-polishing of the peripheral edge of the substrate W is necessary based on the detection result of the residual film R by the residual film detection unit 9. In the present embodiment, the control unit 20 determines whether re-polishing is necessary for each of the top edge portion E1, the upper bevel portion B1, the side portion (apex) B3, the lower bevel portion B2, and the bottom edge portion E2 of the peripheral edge of the substrate W based on the detection result of the residual film by the residual film detection unit 9.

[0079] In the present embodiment, the control unit 20 is configured to determine whether re-polishing of the peripheral edge of the substrate W is necessary based on the residual film rate, which is the ratio of the area of the residual film R in the target region to the total area of the target region in each image. For example, the control unit 20 determines whether re-polishing is necessary based on the residual film rate, which is the ratio of the number of pixels where the residual film R exists to the total number of pixels in the target region in each image.

[0080] In the example shown in FIG. 11, the residual film rate is expressed by the following formula (1). Residual film rate = (N1 + N2 + N3 + ··· + NZ) / (NTa × Z) (1) Here, N1 is the number of pixels of the residual film R in the target region Ta of the image Pa-1, N2 is the number of pixels of the residual film R in the target region Ta of the image Pa-2, N3 is the number of pixels of the residual film R in the target region Ta of the image Pa-3, NZ is the number of pixels of the residual film R in the target region Ta of the image Pa-Z, NTa is the number of pixels of the target region Ta, and Z is the number of images. The number of pixels NTa of the target region Ta may be sent from the detection processing unit 87 to the control unit 20 together with the detection result of the residual film, or may be stored in advance in the storage device 20a of the control unit 20.

[0081] The control unit 20 calculates the residual film rate of the peripheral portion of the substrate W, and determines whether re-polishing of the peripheral portion of the substrate W is necessary based on the residual film rate. For example, the control unit 20 calculates the residual film rate of the peripheral portion of the substrate W, and determines that re-polishing of the peripheral portion of the substrate W is necessary when the residual film rate is greater than the residual film rate threshold. In the example shown in FIG. 11, the control unit 20 determines whether re-polishing of the top edge portion E1 of the substrate W is necessary based on the residual film rate of the top edge portion E1 of the substrate W calculated by the above formula (1).

[0082] In one embodiment, the control unit 20 may determine whether re-polishing of the peripheral portion of the substrate W is necessary based on the thickness of the residual film R existing in the peripheral portion of the substrate W. For example, the control unit 20 determines that re-polishing of the peripheral portion of the substrate W is necessary when the thickness of the residual film R existing in the peripheral portion of the substrate W is greater than the film thickness threshold. In this case, as the thickness of the residual film R existing in the peripheral portion of the substrate W, the average value of the thicknesses of the residual films R existing within the target region of the image may be used.

[0083] When the control unit 20 determines that re-polishing of the peripheral portion of the substrate W is necessary, it is configured to determine the polishing conditions for re-polishing the peripheral portion of the substrate W. Specifically, the control unit 20 is configured to determine the polishing time as the polishing condition for re-polishing the peripheral portion of the substrate W based on the residual film rate of the peripheral portion of the substrate W and the correlation data between the residual film rate and the polishing time. The correlation data between the residual film rate and the polishing time is acquired in advance based on experimental results or the like, and is stored in the storage device 20a of the control unit 20. The correlation data between the residual film rate and the polishing time is data indicating that the greater the residual film rate of the peripheral portion of the substrate W, the longer the polishing time required for re-polishing the peripheral portion of the substrate W.

[0084] In one embodiment, the control unit 20 may be configured to determine the polishing time as the polishing condition for re-polishing the peripheral portion of the substrate W based on the thickness of the residual film R present at the peripheral portion of the substrate W. In this case, the control unit 20 is configured to determine the polishing time as the polishing condition for re-polishing the peripheral portion of the substrate W based on the thickness of the residual film R present at the peripheral portion of the substrate W and the correlation data between the thickness of the residual film R and the polishing time. The correlation data between the thickness of the residual film R and the polishing time is obtained in advance based on experimental results or the like and stored in the storage device 20a of the control unit 20. The correlation data between the thickness of the residual film R and the polishing time is data indicating that the greater the thickness of the residual film R at the peripheral portion of the substrate W, the longer the polishing time required for re-polishing the peripheral portion of the substrate W.

[0085] In one embodiment, the control unit 20 may be configured to determine the polishing time based on the combination of the residual film ratio of the peripheral portion of the substrate W and the thickness of the residual film R present at the peripheral portion of the substrate W.

[0086] Furthermore, the control unit 20 is configured to determine the polishing angle corresponding to the region of the peripheral portion of the substrate W determined to require re-polishing as the polishing condition for re-polishing. The polishing angle is the inclination angle of the polishing heads 30A to 30D. For example, when it is determined that re-polishing of the top edge portion E1 of the substrate W is necessary, the control unit 20 determines the polishing angle corresponding to the top edge portion E1 as the polishing condition for re-polishing the peripheral portion of the substrate W.

[0087] The polishing module 4A or 4B of the polishing unit 4 repolishes the peripheral portion of the substrate W under the determined polishing conditions. Specifically, the polishing module 4A or 4B repolishes the peripheral portion of the substrate W at the determined polishing time and polishing angle by at least one of the polishing heads 30A to 30D. For example, the control unit 20 issues a command to the polishing head tilting mechanism 70A of the polishing module 4A to tilt the polishing head 30A to the determined polishing angle, and issues a command to the air cylinder 35 of the polishing head 30A to press the polishing tape 22A against the peripheral portion of the substrate W with the pressing member 32 for the determined polishing time. In this way, the polishing module 4A repolishes the area of the peripheral portion of the substrate W determined to require repolishing under the determined polishing conditions (polishing time and polishing angle).

[0088] FIG. 12 is a flowchart showing an embodiment of the substrate processing method. The processing flow described below is executed by the substrate processing apparatus described above. In step S101, at least one of the polishing modules 4A and 4B of the polishing unit 4 polishes the peripheral portion of the substrate W according to a predetermined polishing recipe. In step S102, the cleaning unit 6 cleans the substrate W polished by at least one of the polishing modules 4A and 4B. In step S103, the drying unit 7 dries the substrate W cleaned by the cleaning unit 6.

[0089] In step S104, the residual film detection unit 9 detects the residual film on the peripheral portion of the substrate W. In one embodiment, the imaging devices 86A to 86E of the residual film detection unit 9 generate an image of the peripheral portion of the substrate W. The detection processing unit 87 of the residual film detection unit 9 detects the residual film from the hue appearing on the image of the peripheral portion of the substrate W. For example, the detection processing unit 87 may detect the residual film in the target area within the image of the peripheral portion of the substrate W and calculate the area of the residual film.

[0090] In step S105, the control unit 20 determines whether re-polishing of the peripheral portion of the substrate W is necessary based on the detection result of the residual film by the residual film detection unit 9. In one embodiment, the control unit 20 determines whether re-polishing of the peripheral portion of the substrate W is necessary based on the residual film rate, which is the ratio of the area of the residual film R in the target region to the total area of the target region in the image.

[0091] When the control unit 20 determines in step S105 that re-polishing of the peripheral portion of the substrate W is necessary, it determines the polishing conditions for re-polishing (step S106). In one embodiment, the control unit 20 determines the polishing time as the polishing condition for re-polishing the peripheral portion of the substrate W based on the residual film rate of the peripheral portion of the substrate W and the correlation data between the residual film rate and the polishing time. Further, the control unit 20 determines the polishing angle corresponding to the region of the peripheral portion of the substrate W for which re-polishing is determined to be necessary as the polishing condition for re-polishing.

[0092] The polishing module 4A or 4B of the polishing unit 4 re-polishes the peripheral portion of the substrate W under the polishing conditions for re-polishing determined in step S106 (returns to step S101). Specifically, the polishing module 4A or 4B re-polishes the peripheral portion of the substrate W at the determined polishing time and polishing angle by at least one of the polishing heads 30A to 30D. Thereafter, steps S102 to S105 are performed again. The processing flow repeats steps S101 to S106 until the control unit 20 determines in step S105 that re-polishing of the peripheral portion of the substrate W is unnecessary.

[0093] When the control unit 20 determines in step S105 that re-polishing of the peripheral portion of the substrate W is unnecessary, it ends the process. Specifically, the control unit 20 issues a command to the first transfer robot 14 to return the substrate W from the residual film detection unit 9 to the substrate cassette 19 at the load port 2.

[0094] According to the present embodiment, the control unit 20 can appropriately determine the polishing conditions for re-polishing based on the state of the residual film at the peripheral portion of the substrate W.

[0095] In one embodiment, as shown in FIG. 13, the control unit 20 may have a polishing condition determination model 90 constructed by machine learning, and output the polishing conditions for re-polishing the peripheral portion of the substrate W from the polishing condition determination model 90. FIG. 13 is a schematic diagram showing one embodiment of the control unit 20 having the polishing condition determination model 90 and the residual film detection unit 9. The control unit 20 of the present embodiment has the polishing condition determination model 90 stored in the storage device 20a. The polishing condition determination model 90 is a learned model constructed by machine learning. Examples of machine learning include the SVR method (Support Vector Regression method), the PLS method (Partial Least Squares method), the deep learning method, the random forest method, and the decision tree method. In one example, the polishing condition determination model 90 is composed of a neural network constructed by the deep learning method.

[0096] The training data used for the machine learning of the polishing condition determination model 90 includes an image of the peripheral portion of the substrate and the polishing conditions (that is, the polishing time and the polishing angle) necessary to remove the residual film appearing on the image by polishing. The image of the peripheral portion of the substrate is an explanatory variable, and the polishing conditions (that is, the polishing time and the polishing angle) are objective variables. The above-mentioned polishing conditions included in the training data are correct labels and are obtained from the results of actual polishing of the substrate.

[0097] FIG. 14 is a schematic diagram showing an example of the polishing condition determination model 90 constructed using the deep learning method. The polishing condition determination model 90 has an input layer 91, a plurality of hidden layers (also referred to as intermediate layers) 92, and an output layer 93. The polishing condition determination model 90 shown in FIG. 14 has four hidden layers 92, but the configuration of the polishing condition determination model 90 is not limited to the embodiment shown in FIG. 14.

[0098] When an image of the peripheral portion of the substrate is input to the input layer 91, the polishing condition determination model 90 is configured to output, from the output layer 93, the polishing conditions (i.e., polishing time and polishing angle) for re-polishing the peripheral portion of the substrate. The construction of the polishing condition determination model 90 using deep learning is performed as follows. An image of the peripheral portion of the substrate is input to the input layer 91 shown in FIG. 14. The control unit 20 compares the polishing conditions for re-polishing the peripheral portion of the substrate output from the output layer 93 with the polishing conditions (correct labels) corresponding to the images of the peripheral portions of the substrates included in the training data, and adjusts the parameters (weights, thresholds, etc.) of each node (neuron) so as to minimize the error. Thereby, the polishing condition determination model 90 is learned to output, from the output layer 93, appropriate polishing conditions for re-polishing the peripheral portion of the substrate based on the image of the peripheral portion of the substrate input to the input layer 91.

[0099] By repeating the above learning using images of the peripheral portions of a plurality of substrates, the polishing condition determination model 90 is constructed. The polishing condition determination model 90 based on machine learning basically has a low prediction accuracy for input data that has not been experienced. Therefore, by using a large number of images in which the remaining film appears in different modes, the accuracy of the polishing conditions for re-polishing the peripheral portion of the substrate output from the polishing condition determination model 90 can be improved.

[0100] The determination of the polishing conditions for re-polishing the peripheral portion of the substrate W using the polishing condition determination model 90 is performed as follows. The control unit 20 inputs an image of the peripheral portion of the substrate W generated by the imaging devices 86A to 86E of the remaining film detection unit 9 to the input layer 91 of the polishing condition determination model 90. In the present embodiment, the detection result of the remaining film at the peripheral portion of the substrate W by the remaining film detection unit 9 is an image of a preset target area. The control unit 20 executes an operation according to the algorithm defined by the polishing condition determination model 90. The control unit 20 outputs the polishing conditions for re-polishing the peripheral portion of the substrate W from the output layer 93 of the polishing condition determination model 90, and determines the polishing conditions for re-polishing the peripheral portion of the substrate W.

[0101] In one embodiment, the control unit 20 may output an estimated value of the remaining film thickness in addition to the polishing conditions for the peripheral portion of the substrate W from the polishing condition determination model 90. In this case, the correct labels used in the training data include the measured value of the remaining film thickness at the peripheral portion of the substrate and the polishing conditions (i.e., polishing time and polishing angle) necessary to remove the remaining film appearing in the image by polishing.

[0102] In one embodiment, after repolishing the peripheral portion of the substrate W under the polishing conditions determined using the polishing condition determination model 90, the remaining film at the peripheral portion of the substrate W may be detected again by the remaining film detection unit 9. In this case, the polishing condition determination model 90 may be updated by performing machine learning using the image of the peripheral portion of the substrate W before repolishing and the detection result of the remaining film after repolishing as training data.

[0103] The above-described embodiments are described for the purpose of enabling those having ordinary knowledge in the technical field to which the present invention pertains to practice the present invention. Various modifications of the above embodiments can be naturally made by those skilled in the art, and the technical idea of the present invention can also be applied to other embodiments. Therefore, the present invention is not limited to the described embodiments, but is construed in the broadest scope in accordance with the technical idea defined by the claims.

Description of Reference Numerals

[0104] 1 Housing 2 Load Port 4 Polishing Unit 4A, 4B Polishing Modules 6 Cleaning Unit 7 Drying Unit 9 Remaining Film Detection Unit 11 First Temporary Stage 12 Second Temporary Stage 14 First Transfer Robot 15 Second Transfer Robot 16 Third Transfer Robot 17 Fourth Transfer Robot 19 Substrate Cassette 20 Control Unit 20a Storage Device 20b computing device 22A, 22B, 22C, 22D grinding tape 25 substrate holding part 27 holding stage 28 shaft 29 holding stage drive mechanism 30A, 30B, 30C, 30D grinding head 32 pressing member 35 air cylinder (actuator) 36 tape feeding mechanism 38 grinding head support member 40A, 40B, 40C, 40D grinding tape supply mechanism 41 tape unwinding reel 42 tape winding reel 44, 45, 46, 47 guide roller 48 reel base 51 lower supply nozzle 52 upper supply nozzle 60 grinding head translation mechanism 61 movable plate 63 connecting member 64 guide rail 66 connecting shaft 67 air cylinder (actuator) 68 base plate 70A, 70B, 70C, 70D grinding head tilting mechanism 72 crank arm 73 arm rotating device 80 substrate holding device 82 holding stage 83 shaft 84 holding stage rotation mechanism 86A, 86B, 86C, 86D, 86E imaging device 87 detection processing unit 87a storage device 87b computing device 90 grinding condition determination model 91 input layer 92 hidden layer (intermediate layer) 93 output layer

Claims

1. A polishing unit that polishes the peripheral edge of the substrate, A residual film detection unit that detects the residual film on the peripheral edge of the substrate polished by the polishing unit, Based on the detection result of the residual film by the residual film detection unit, it determines whether re-polishing of the peripheral edge of the substrate is necessary, and when it is determined that re-polishing is necessary, based on the detection result of the residual film, it includes a control unit that determines the polishing conditions for the re-polishing, The polishing unit is configured to re-polish the peripheral edge of the substrate under the determined polishing conditions, a substrate processing apparatus.

2. The residual film detection unit, An imaging device that generates an image of the peripheral edge of the substrate, The substrate processing apparatus according to claim 1, comprising a detection processing unit that detects the residual film on the peripheral edge of the substrate based on the image.

3. The residual film detection unit further includes a substrate holding device that holds the substrate and rotates the substrate, The substrate processing apparatus according to claim 2, wherein the image is an image of the entire circumference of the peripheral edge of the substrate.

4. The detection processing unit is configured to calculate the area of the residual film from the hue appearing on the image, The control unit is configured to determine whether re-polishing of the peripheral edge of the substrate is necessary based on the residual film rate, which is the ratio of the area of the residual film in the target area to the total area of the target area in the image, of the substrate processing apparatus according to claim 2.

5. The control unit is configured to determine the polishing time as the polishing condition based on the residual film rate and the correlation data between the residual film rate and the polishing time, of the substrate processing apparatus according to claim 4.

6. The residual film detection unit is configured to detect the residual film in each of a plurality of regions on the peripheral edge that are arranged in the thickness direction of the substrate, The control unit, Based on the detection result of the residual film, determines whether re-polishing is necessary in each of the plurality of regions, As the polishing condition for the re-polishing, it is configured to determine the polishing angle corresponding to the region determined to require re-polishing, The plurality of regions are regions polished at different polishing angles by the polishing unit, of the substrate processing apparatus according to claim 1.

7. The residual film detection unit, A plurality of imaging devices that respectively generate images of the plurality of regions, The substrate processing apparatus according to claim 6, comprising a detection processing unit that detects the residual film in each of the plurality of regions based on the images of the plurality of regions.

8. The residual film detection unit, An imaging device that generates an image of the peripheral portion of the substrate; A detection processing unit that detects the remaining film on the peripheral portion of the substrate based on the image; The control unit has a polishing condition determination model constructed by machine learning, inputs the image into the polishing condition determination model, and is configured to output the polishing conditions for the repolishing from the polishing condition determination model. The substrate processing apparatus according to claim 1.

9. Detect the remaining film on the peripheral portion of the substrate polished by the polishing unit; Based on the detection result of the remaining film, determine whether repolishing of the peripheral portion of the substrate is necessary; When it is determined that repolishing is necessary, based on the detection result of the remaining film, determine the polishing conditions for the repolishing; A substrate processing method in which the peripheral portion of the substrate is repolished under the determined polishing conditions by the polishing unit.

10. Detecting the remaining film on the peripheral portion of the substrate is generating an image of the peripheral portion of the substrate by an imaging device and detecting the remaining film on the peripheral portion of the substrate based on the image. The substrate processing method according to claim 9.

11. Generating the image of the peripheral portion of the substrate is generating an image of the entire circumference of the peripheral portion of the substrate while rotating the substrate by a substrate holding device. The substrate processing method according to claim 10.

12. Detecting the remaining film on the peripheral portion of the substrate is calculating the area of the remaining film from the hue appearing on the image; Determining whether repolishing of the peripheral portion of the substrate is necessary is determining whether repolishing of the peripheral portion of the substrate is necessary based on a remaining film rate that is the ratio of the area of the remaining film in the target region to the total area of the target region in the image. The substrate processing method according to claim 10.

13. Determining the polishing conditions for the repolishing is determining the polishing time as the polishing condition based on the remaining film rate and correlation data between the remaining film rate and the polishing time. The substrate processing method according to claim 12.

14. Detecting the remaining film on the peripheral portion of the substrate is detecting the remaining film in each of a plurality of regions of the peripheral portion arranged in the thickness direction of the substrate; Determining whether repolishing of the peripheral portion of the substrate is necessary is determining whether repolishing is necessary in each of the plurality of regions based on the detection result of the remaining film. Determining the polishing conditions for the repolishing includes determining, as the polishing conditions for the repolishing, a polishing angle corresponding to a region determined to require repolishing. The substrate processing method according to claim 9, wherein the plurality of regions are regions polished at different polishing angles by the polishing unit.

15. Detecting the residual film at the peripheral portion of the substrate is generating an image of the peripheral portion of the substrate by an imaging device and detecting the residual film at the peripheral portion of the substrate based on the image. Determining the polishing conditions for the repolishing is inputting the image into a polishing condition determination model constructed by machine learning and outputting the polishing conditions for the repolishing from the polishing condition determination model, according to the substrate processing method of claim 9.

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