Centering device, centering method, and substrate processing device

Abstract

The present invention provides a centering device, a centering method, and a substrate processing device to align the center of a circular plate-shaped substrate placed on the upper surface of a substrate support portion with the center of the substrate support portion with excellent productivity. The present invention surrounds the substrate on the upper surface of the substrate support portion with a first abutting member at a first reference position, a second abutting member at a second reference position, and a third abutting member at a third reference position in a horizontal plane. Also, by repeatedly performing slight movements of the three abutting members, the substrate is gradually approached while keeping the distance from the center of the substrate support portion the same. In the approaching movement, the abutting members abut the substrate in turn, and the substrate is horizontally moved toward the center of the substrate support portion. As a result, at the time when the substrate is clamped with the three abutting members, the center of the substrate is aligned with the center of the substrate support portion, and the centering process is completed.

Description

Technical Field

[0001] This invention relates to a centering technique for aligning the center of a circular plate-shaped substrate placed on the upper surface of a substrate support with the center of the substrate support, and a substrate processing apparatus for processing the substrate using this technique. The processing includes bevel etching.

[0002] The disclosures of the Japanese application specification, drawings, and claims shown below are incorporated herein by reference in their entirety:

[0003] Japan Special Appeal 2022-17003 (applied on February 7, 2022). Background Technology

[0004] A substrate processing apparatus is known in which a processing liquid is supplied to the periphery of a substrate, such as a semiconductor wafer, while the substrate is rotated to perform chemical treatment, cleaning, or other similar processes. For example, in the apparatus described in Japanese Patent Application Publication No. 2019-149423, the substrate is held in place by being supported from below by a rotating chuck (an example of the "substrate support" of this invention). In this case, if the center of the rotating chuck is misaligned with the center of the substrate, the processing quality is reduced. Therefore, in the aforementioned apparatus, a so-called centering process is performed before processing the substrate to reduce the eccentricity of the substrate relative to the rotating chuck. Summary of the Invention

[0005] The problem that the invention aims to solve

[0006] In the aforementioned existing apparatus, centering is performed in two stages. First, the eccentricity of the substrate relative to the rotary chuck is measured. Then, the substrate on the rotary chuck is horizontally pushed using a pusher, thereby moving the center of the substrate toward the center (rotation axis) of the rotary chuck. Therefore, there is room for improvement in productivity.

[0007] The present invention was made in view of the above-mentioned problems, and its object is to provide a centering technology that enables the center of a circular plate-shaped substrate placed on the upper surface of a substrate support to be aligned with the center of the substrate support with excellent productivity, and a substrate processing apparatus using the centering technology.

[0008] Solution for solving the problem

[0009] The first aspect of the present invention is a centering device that positions the substrate by horizontally moving it on the upper surface of the substrate support, such that the center of the circular plate-shaped substrate placed on the upper surface of the substrate support is aligned with the center of the substrate support. The centering device is characterized by comprising: a first abutting member, which is freely movable in a horizontal plane from a first reference position toward a first horizontal direction toward the center of the substrate support, the first reference position being a reference distance from the center of the substrate support that is longer than the radius of the substrate; a second abutting member, which is freely movable in a horizontal plane from a second reference position toward a second horizontal direction different from the direction toward the center of the substrate support but closer to the substrate, the second reference position being offset from the center of the substrate support relative to the center of the first abutting member by a virtual line extending from the center of the substrate support toward the first horizontal direction, and being a reference distance from the center of the substrate support; and a third abutting member, which is movable in a horizontal plane... The first, second, and third abutment members are movable from a third reference position toward a third horizontal direction that is different from the direction toward the center of the substrate support and closer to the substrate. The third reference position is on the opposite side of the center of the substrate support from the first abutment member and on the opposite side of the virtual line from the second abutment member, and is a reference distance away from the center of the substrate support. The moving mechanism moves the first abutment member, the second abutment member, and the third abutment member toward the first horizontal direction, the second horizontal direction, and the third horizontal direction, respectively. The control unit controls the moving mechanism to repeatedly perform small movements that move the first abutment member, the second abutment member, and the third abutment member by a first movement amount, a second movement amount, and a third movement amount, respectively, so that the distances of the first abutment member, the second abutment member, and the third abutment member from the center of the substrate support are kept the same. If it is confirmed that the substrate is clamped by the first abutment member, the second abutment member, and the third abutment member, the small movements are stopped.

[0010] Furthermore, the second aspect of the present invention is a centering method, which is a centering method for aligning the center of a circular plate-shaped substrate with the center of a substrate support portion. The method is characterized by comprising: a step of placing the substrate on the upper surface of the substrate support portion in a horizontal plane, with the first abutting member at a first reference position, the second abutting member at a second reference position, and the third abutting member at a third reference position. The first reference position is located at a reference distance from the center of the substrate support portion that is longer than the radius of the substrate. The second reference position is located opposite the center of the substrate support portion from the center of the first abutting member, deviating from a virtual line extending from the first reference position through the center of the substrate support portion and from the center of the substrate support portion by a reference distance. The third reference position is located opposite the center of the substrate support portion from the center of the first abutting member and opposite the virtual line from the center of the substrate support portion. The center of the substrate is moved away from the reference distance; the process of repeating the micro-movement is carried out in a state where the substrate is horizontally and freely placed on the upper surface of the substrate support, and the distances of the first abutting member, the second abutting member, and the third abutting member from the center of the substrate support are kept the same. The first abutting member is moved from the first reference position toward the center of the substrate support in a first horizontal direction, the second abutting member is moved from the second reference position to a second horizontal direction that is different from the direction toward the center of the substrate support and closer to the substrate by a second movement amount, and the third abutting member is moved from the third reference position to a third horizontal direction that is different from the direction toward the center of the substrate support and closer to the substrate by a third movement amount; and the process of repeating the micro-movement is stopped if it is confirmed that the substrate is clamped by the first abutting member, the second abutting member, and the third abutting member.

[0011] Furthermore, the third aspect of the present invention is characterized by comprising: a substrate support having an upper surface supporting a substrate in a horizontal position; the aforementioned centering device; an suction unit that vents air between the substrate positioned by the centering device and the substrate support to adsorb and hold the substrate on the substrate support; a rotation drive unit that rotates the substrate support holding the substrate around the center of the substrate support; and a processing liquid supply mechanism that supplies processing liquid to the periphery of the substrate that rotates integrally with the substrate support around the center of the substrate support.

[0012] In this invention, within a horizontal plane, the substrate is surrounded by a first abutting member located at a first reference position, a second abutting member located at a second reference position, and a third abutting member located at a third reference position. These three abutting members gradually approach the substrate while maintaining a constant distance from the center of the substrate support through repeated minute movements. During this approach movement, the abutting members sequentially abut against the substrate, causing the substrate to move horizontally towards the center of the substrate support. As a result, the center of the substrate held by these three abutting members coincides with the center of the substrate support.

[0013] Invention Effects

[0014] As described above, according to the present invention, by repeating the small movements of the three abutting parts, the center of the circular plate-shaped substrate placed on the upper surface of the substrate support can be aligned with the center of the substrate support, enabling substrate centering processing with excellent productivity.

[0015] Not all of the constituent elements of the various solutions of the present invention described above are essential. To solve some or all of the aforementioned problems, or to achieve some or all of the effects described in this specification, some of the constituent elements can be appropriately modified, deleted, replaced with new constituent elements, or have some of the limiting content deleted. Furthermore, to solve some or all of the aforementioned problems, or to achieve some or all of the effects described in this specification, some or all of the technical features included in one solution of the present invention can be combined with some or all of the technical features included in other solutions of the present invention as an independent embodiment of the present invention. Attached Figure Description

[0016] Figure 1 This is a diagram illustrating a substrate processing system equipped with one embodiment of the substrate processing apparatus of the present invention.

[0017] Figure 2 This is a diagram that schematically illustrates the structure of one embodiment of the substrate processing apparatus.

[0018] Figure 3 This is a perspective view showing the structure of the substrate holding section and centering mechanism of the substrate processing apparatus.

[0019] Figure 4 It is a diagram that schematically represents the operation of a centering mechanism.

[0020] Figure 5 It is a graph showing the variation of load torque relative to the change in distance from the center of the base to the protruding part in the first embodiment.

[0021] Figure 6 This is a schematic diagram illustrating the structure of a second embodiment of the centering device of the present invention.

[0022] Figure 7 This is a schematic diagram illustrating the structure of a third embodiment of the centering device of the present invention.

[0023] Figure 8 It is a graph showing the change in the amount of movement associated with the change in the distance from the center of the base to the protruding part in the third embodiment.

[0024] In the picture:

[0025] 3—Centering mechanism; 4—Processing fluid supply mechanism; 9—Control unit (control section); 10—Substrate processing device; 21—Rotating base (substrate support); 21C—Center (of the rotating base); 23—Rotation drive section; 24—Suction pump (suction section); 31—First abutting member; 32—Second abutting member; 33—Third abutting member; 34—Moving mechanism; 35, 37, 38—Single moving part; 36—Multiple moving parts; 211—Upper surface (of the rotating base); 231, 352, 362—Rotary motor; S—Substrate; SC—Center (of the substrate); VL—Virtual line. Detailed Implementation

[0026] Figure 1 This diagram illustrates a substrate processing system equipped with an embodiment of the substrate processing apparatus of the present invention. The substrate processing system 100 includes a substrate processing unit 110 for processing substrates S and a sorting unit 120 coupled to the substrate processing unit 110. The sorting unit 120 includes: a container holding unit 121 capable of holding multiple containers C (such as FOUP (Front Opening Unified Pod), SMIF (Standard Mechanical Interface), OC (Open Cassette), etc.) for accommodating substrates S in a sealed state; and a sorting robot 122 for accessing the containers C held in the container holding unit 121, removing unprocessed substrates S from the containers C, or storing processed substrates S in the containers C. In each container C, multiple substrates S are accommodated in a substantially horizontal position.

[0027] The indexing robot 122 includes a base portion 122a fixed to the device frame, a multi-joint arm 122b disposed on the base portion 122a in a manner rotatable about a vertical axis, and a hand portion 122c mounted on the front end of the multi-joint arm 122b. The hand portion 122c is configured to place and hold the substrate S on its upper surface. Since indexing robots with such a multi-joint arm and substrate holding hand are known, detailed description is omitted.

[0028] The substrate processing unit 110 includes a substrate handling robot 111 positioned approximately in the center when viewed from above, and a plurality of processing units 1 arranged to surround the substrate handling robot 111. Specifically, the plurality of processing units 1 are arranged facing the space in which the substrate handling robot 111 is located. The substrate handling robot 111 randomly visits these processing units 1 to transfer substrates S. On the other hand, each processing unit 1 performs a predetermined process on the substrate S. In this embodiment, one of these processing units 1 corresponds to the substrate processing apparatus 10 of the present invention.

[0029] Figure 2 This is a diagram that schematically illustrates the structure of one embodiment of the substrate processing apparatus. Figure 3 This is a perspective view showing the structure of the substrate holding section and centering mechanism of the substrate processing apparatus. Figure 4 This diagram schematically illustrates the operation of the centering mechanism. The substrate processing apparatus 10 is an apparatus that performs bevel etching as an example of the "processing" of the present invention, supplying processing liquid to the periphery of the upper surface of the substrate S within the processing chamber. For this purpose, the substrate processing apparatus 10 includes a substrate holding section, a centering mechanism 3 which is the main structure of the centering device of the present invention, and a processing liquid supply mechanism 4. Their operation is controlled by a control unit 9 that controls the entire apparatus.

[0030] The substrate holding section includes a rotating base 21, which is a circular plate-shaped component smaller than the substrate S. The rotating base 21 is supported by a rotating shaft 22 extending downward from the center of its lower surface, making its upper surface 211 horizontal. The rotating shaft 22 is rotatably supported by a rotating drive unit 23. The rotating drive unit 23 houses a rotating motor 231, which rotates according to control commands from the control unit 9. Driven by this rotational force, the rotating base 21 rotates about a vertical axis AX (single-dot dashed line) extending vertically through its center 21C. Figure 2 In the middle, the vertical direction is the up-down direction. Additionally, with... Figure 2 The plane perpendicular to the paper is the horizontal plane. Additionally, to clarify... Figure 2 In the accompanying diagrams, the directional relationships should be appropriately labeled with a coordinate system that uses the Z-axis as the vertical direction and the XY plane as the horizontal plane.

[0031] The upper surface 211 of the rotating base 21 has a width sufficient to support the substrate S, allowing the substrate S to be placed on the upper surface 211. Although not shown in the figure, the upper surface 211 is provided with a plurality of suction holes, suction grooves, etc. These suction holes, etc., are connected to the suction pump 24 via suction pipes 241. When the suction pump 24 operates according to control commands from the control unit 9, it applies suction force to the rotating base 21. As a result, air is expelled between the upper surface 211 of the rotating base 21 and the lower surface of the substrate S, and the substrate S is suctioned and held on the rotating base 21. The substrate S, thus suctioned and held, rotates together with the rotation of the rotating base 21 about the vertical axis AX. Therefore, when the center SC of the substrate S is not aligned with the center 21C of the rotating base 21, i.e., the substrate S is eccentric, the quality of the bevel etching process is reduced.

[0032] Therefore, in this embodiment, a centering mechanism 3 is provided. The centering mechanism 3 performs a centering process during the period when the suction performed by the suction pump 24 stops (i.e., during the period when the substrate S can move horizontally on the upper surface 211 of the rotating base 21). This centering process eliminates the aforementioned eccentricity, and the center SC of the substrate S coincides with the center 21C of the rotating base 21. Furthermore, the detailed structure and operation of the centering mechanism 3 will be described later.

[0033] To perform bevel etching on the substrate S that has undergone centering treatment, a processing liquid supply mechanism 4 is provided. The processing liquid supply mechanism 4 includes a processing liquid nozzle 41, a nozzle moving part 42 for moving the processing liquid nozzle 41, and a processing liquid supply part 43 for supplying processing liquid to the processing liquid nozzle 41. The nozzle moving part 42 moves the processing liquid nozzle 41 as... Figure 2 As shown by the solid line in the figure, it moves between a retreat position that moves laterally from above the substrate S and a processing position above the periphery of the substrate S, as shown by the dashed line in the figure.

[0034] The processing liquid nozzle 41 is connected to the processing liquid supply unit 43. Furthermore, if appropriate processing liquid is supplied from the processing liquid supply unit 43 to the processing liquid nozzle 41, which is positioned at the processing location, the processing liquid is discharged from the processing liquid nozzle 41 to the periphery of the rotating substrate S. Thus, a bevel etching process based on the processing liquid is performed on the entire periphery of the substrate S.

[0035] Additionally, although omitted in Figure 2 The illustration shows that the splash guard is configured to surround the substrate holding part from the side. During the angled etching process, the splash guard traps droplets of the processing liquid ejected from the substrate S, effectively preventing the droplets from scattering around the device.

[0036] Next, refer to Figures 2 to 4The structure of the centering mechanism 3 will be described. The centering mechanism 3 has the function of positioning the substrate S by horizontally moving it on the upper surface 211 of the rotating base 21, so that the center SC of the substrate S placed on the upper surface 211 of the rotating base 21 coincides with the center 21C of the rotating base 21. Figure 3 As shown, the centering mechanism 3 has an abutment member 31 disposed in the X2 direction (right-hand direction in the figure) relative to the center 21C of the rotating base 21 in the X direction, and abutment members 32 and 33 disposed in the X1 direction (left-hand direction in the figure). In addition, the centering mechanism 3 has a moving mechanism 34 for moving the abutment members 31 to 33 in the horizontal direction.

[0037] The moving mechanism 34 has a single moving part 35 for moving the abutting member 31 and a multiple moving part 36 for moving the abutting members 32 and 33 together. The single moving part 35 is disposed on the X2 direction side relative to the center 21C of the rotating base 21, while the multiple moving part 36 is disposed on the X1 direction side.

[0038] The single moving part 35 includes a fixed base 351, a rotary motor 352, a power transmission part 353, and a slider 354. The rotary motor 352 is mounted relative to the fixed base 351, and the power transmission part 353 and the slider 354 are stacked sequentially on the fixed base 351. The rotary motor 352 is a drive source for moving the contact member 31 in the X direction. When the rotary motor 352 operates according to a control command from the control unit 9, a rotating shaft (not shown) rotates. This rotating shaft extends from the upper part of the fixed base 351 to the power transmission part 353, and the rotational driving force generated by the rotary motor 352 is transmitted to the power transmission part 353. The power transmission part 353, for example, through a rack and pinion structure, converts the rotational motion corresponding to the rotational driving force into linear motion in the X direction and transmits it to the slider 354. As a result, the slider 354 reciprocates a distance in the X direction corresponding to the amount of rotation. Consequently, the contact member 31, mounted on the upper part of the slider 354, moves in the X direction as the slider 354 moves.

[0039] The multi-moving unit 36 ​​is essentially the same as the single-moving unit 35, except for the structural differences in the slider 364. That is, the multi-moving unit 36 ​​applies rotational driving force generated by the rotary motor 362 mounted on the fixed base 361 to the slider 364 via the power transmission unit 363, causing the slider 364 to move in the X direction. The two arms 364a and 364b extending along the X2 direction at the upper part of the slider 364 are separated from each other in the Y direction, forming a roughly C-shape when viewed from above. Furthermore, abutment members 32 and 33 are respectively mounted at the X2 direction ends of the arms 364a and 364b. Therefore, when the rotary motor 362 operates according to control commands from the control unit 9, the slider 364 reciprocates along the X direction a distance corresponding to the rotation amount of the rotary motor 362, similar to the single-moving unit 35. As a result, the abutment members 32 and 33 mounted on the slider 364 move in the X direction as the slider 364 moves.

[0040] In any of the abutting members 31 to 33, the end opposite to the substrate S protrudes in a mouth shape. That is, the protruding portion (front end) of the abutting members 31 to 33 has a sharp shape. Therefore, the abutting members 31 to 33 can make point contact with the side of the substrate S supported by the upper surface 211 of the rotating base 21. When the abutting member 31 moves in the X1 direction via the single moving part 35, the protruding portion 311 of the abutting member 31 advances toward the center 21C of the rotating base 21 and abuts against the side of the substrate S. Thus, in this embodiment, the moving direction D1 of the abutting member 31 for abutting against the substrate S is the X1 direction, which corresponds to the "first horizontal direction" of the present invention. Furthermore, after abutting, the abutting member 31 moves further in the D1 direction, thereby pushing the substrate S in the X1 direction while moving horizontally in the X1 direction on the upper surface 211 of the rotating base 21. Thus, in this embodiment, in order to facilitate the understanding of the invention, Figure 3 as well as Figure 4 The text further describes a virtual line VL extending from the center 21C of the rotating base 21 in the X1 direction. This corresponds to the "virtual line" of the present invention. Hereinafter, the structure of the centering mechanism 3 will continue to be described while making appropriate use of the virtual line VL.

[0041] The movement of the contacting members 32 and 33, performed by the multiple moving parts 36, differs in part from the movement of the contacting member 31. This is because, in the horizontal plane, the contacting members 32 and 33 are symmetrically arranged with respect to the virtual line VL, and move along the X direction in this arrangement. More specifically, as... Figure 4As shown in column (a), the abutting member 32 is disposed offset from the virtual line VL towards the Y2 direction by a predetermined distance W (however, shorter than the radius rs of the substrate S). On the other hand, the abutting member 33 is disposed offset from the virtual line VL on the opposite side of the abutting member 32, i.e., in the Y1 direction, by the same distance W. Therefore, when the abutting members 32 and 33 are moved in the X2 direction by the multiple moving part 36, the protruding part 321 of the abutting member 32 abuts against the substrate side surface on the Y2 direction side of the virtual line VL, and the protruding part 331 of the abutting member 33 abuts against the substrate side surface on the Y1 direction side of the virtual line VL. Thus, in this embodiment, the moving direction D2 of the abutting member 32 for abutting against the substrate S is the X2 direction, which corresponds to the "second horizontal direction" of the present invention. In addition, the moving direction D3 of the abutting member 33 for abutting against the substrate S is also the X2 direction, which corresponds to the "third horizontal direction" of the present invention. Therefore, in order to keep the distance from the center 21C of the rotating base 21 to each of the protruding parts 311, 321, 331 the same while moving the protruding parts 311, 321, 331, it is necessary to make the amount of movement per unit time different on the abutting member 31 and the abutting members 32, 33. For this, refer to... Figure 4 A detailed description is provided, and the centering process utilizing the aforementioned movement method is explained.

[0042] In order to place the substrate S on the upper surface 211 of the rotating base 21, it is preferable to position the protruding portions 311, 321, and 331 at reference positions, taking into account at least the maximum value of the outer diameter tolerance of the substrate S. For example, in a substrate S with a diameter of 300 mm, the outer diameter tolerance is 0.2 mm. Therefore, the protruding portions 311, 321, and 331 need to be located at a distance of 150.1 mm or more from the center 21C of the rotating base 21. In this embodiment, this distance is referred to as the "reference distance r0". Figure 4 As shown in column (a), the reference circle is a circle (single-dot dashed line) with a radius of 21C centered on the center of the rotating base 21 and a reference distance r0.

[0043] Next, the case where the abutting members 31 to 33 are positioned such that the protruding parts 311, 321, and 331 are located on the reference circle, and then the protruding parts 311, 321, and 331 are moved toward the substrate S, is investigated. In this case, the position of the abutting member 31 for positioning the protruding part 311 on the reference circle corresponds to the "first reference position" of the present invention, the position of the abutting member 32 for positioning the protruding part 321 on the reference circle corresponds to the "second reference position" of the present invention, and the position of the abutting member 33 for positioning the protruding part 331 on the reference circle corresponds to the "third reference position" of the present invention.

[0044] Here, we examine the case where the abutting members 31 to 33 are positioned at the first reference position, the second reference position, and the third reference position, respectively, and the abutting member 31 moves slightly toward the substrate S in the D1 direction (X1 direction) with a first movement amount Δd1. Correspondingly, when the abutting members 32 and 33 are moved slightly in the D2 direction (X2 direction) by the same distance, the distances from the center 21C of the rotating base 21 to the protruding portions 311, 321, and 331 are inconsistent. Therefore, if the slight movements of the abutting members 31 to 33 are repeated with a uniform movement amount per unit time, the center SC of the substrate S will not coincide with the center 21C of the rotating base 21.

[0045] In contrast, such as Figure 4 As shown in column (b), the distance Δd2 (corresponding to the "second movement amount" of the present invention) for causing the abutment member 32 to move slightly and the distance Δd3 (corresponding to the "third movement amount" of the present invention) for causing the abutment member 33 to move slightly can be set as follows:

[0046] Δd2=Δd3=r1·cosθ1-r2·cosθ2

[0047] =r1·cos(sin -1 (W / r1))-r2·cos(sin) -1 (W / r2)

[0048] r1=r0

[0049] r2=r1-Δd1

[0050] in,

[0051] r1: The distance from the center 21C before the minute movement to the protruding part 321.

[0052] θ1: The angle formed by the straight line connecting the center 21C and the protruding part 321 before the minute movement, and the virtual line VL.

[0053] r2: The distance from the center 21C after the slight movement to the protruding part 321.

[0054] θ2: The angle formed by the straight line connecting the center 21C and the protruding part 321 after the slight movement, and the virtual line VL.

[0055] W: The separation distance from the virtual line VL to the contact part 32.

[0056] In this case, even after a slight movement, the distance from the center 21C of the rotating base 21 to the protruding portions 311, 321, and 331 remains consistent. By repeatedly performing such slight movements, while maintaining the same distance from the center 21C of the rotating base 21 to the protruding portions 311, 321, and 331, the abutting members 31-33 approach the substrate S. Thus, for example, when a... Figure 4 In the case of eccentricity as shown, during the repeated process of the aforementioned minute movements, the initial contacting member 31 contacts the substrate S, causing the substrate S to move in the D1 direction (see reference). Figure 4 (c) column). Next, the abutting member 32 abuts against the substrate S pushed by the abutting member 31 and moves horizontally. And, as Figure 4 As shown in column (d), when the distance from the center 21C of the rotating base 21 to the protruding parts 311, 321, and 331 is equal to the radius of the substrate S, the final abutting member 33 also abuts against the substrate S. In this way, the movement of the substrate S is stopped by clamping it with the abutting members 31-33, and the center SC of the substrate S coincides with the center 21C of the rotating base 21. This allows for the centering of the substrate S.

[0057] In this embodiment, which includes the aforementioned centering mechanism 3, the control unit 9 controls each part of the substrate processing apparatus 10 to perform the aforementioned centering process and subsequent bevel etching process. The control unit 9 includes an arithmetic processing unit 91 composed of a computer having a CPU (Central Processing Unit), RAM (Random Access Memory), etc.; a storage unit 92 such as a hard disk drive; and a motor control unit 93.

[0058] The arithmetic processing unit 91 appropriately reads the centering program and the bevel etching program pre-stored in the storage unit 92, expands them to RAM (not shown), and performs... Figure 4 The centering process and bevel etching process are shown. Specifically, during the centering process, the arithmetic processing unit 91 calculates the first movement amount Δd1 to the third movement amount Δd3, and controls the rotary motors 352 and 362 of the moving mechanism 34 via the motor control unit 93 based on these movement amounts Δd1 to Δd3. Furthermore, the arithmetic processing unit 91 calculates the load torque in the single moving part 35 based on the motor current value supplied to the rotary motor 352, and calculates the load torque in the multiple moving parts 36 based on the motor current value supplied to the rotary motor 362. Here, during the repeated small movements, as the distance from the center 21C of the rotating base 21 to the protruding parts 311, 321, 331 (distance from the base center to the protruding parts) changes, the load torque, for example, ... Figure 5The movement changes as shown. As shown in the figure, at the moment when the distance is the same as the radius rs of the substrate S, i.e., when the abutment members 31-33 clamp the substrate S, the load torque increases sharply almost simultaneously in both the single moving part 35 and the multiple moving parts 36. Therefore, the calculation and processing unit 91 determines that the centering process is completed when the load torque exceeds the threshold, and stops the movement of the abutment members 31-33. In addition, in this embodiment, the change in load torque is monitored for all motors 352 and 362, but the stopping time of the movement of the abutment members 31-33 can also be determined by monitoring only one motor. Alternatively, the load torque can be calculated based on factors other than the motor current value.

[0059] As described above, in this embodiment, by repeatedly performing minute movements of the abutment members 31-33, the distance from the center 21C of the rotating base 21 to the protruding portions 311, 321, and 331 is kept constant while the abutment members 31-33 gradually approach the substrate S. Furthermore, by using these three abutment members 31-33 to clamp the substrate S, the center SC of the substrate S is aligned with the center 21C of the rotating base 21. Thus, centering is performed only through the repetitive action of minute movements of the abutment members 31-33, enabling centering processes to be performed with excellent productivity.

[0060] Furthermore, the completion of the centering process is confirmed based on the load torque variation, and the movement of the contacting parts 31 to 33 is immediately stopped. Therefore, the centering process can be completed at the appropriate time without causing damage to the substrate S. The same applies to the embodiments described later.

[0061] As described above, in the substrate processing apparatus 10, the combination of the centering mechanism 3 and the control unit 9 corresponds to the first embodiment of the centering device of the present invention. That is, the abutting members 31 to 33 correspond to examples of the "first abutting member," "second abutting member," and "third abutting member" of the present invention, respectively. Furthermore, the control unit 9 corresponds to an example of the "control unit" of the present invention. Additionally, the rotating base 21 and the center 21C correspond to examples of the "substrate support" and the "center of the substrate support" of the present invention, respectively. Furthermore, the suction pump 24 corresponds to an example of the "suction unit" of the present invention.

[0062] Furthermore, in the first embodiment described above, the two abutting members 32 and 33 are moved in the D2 direction (X2 direction) and the D3 direction (X2 direction) respectively by the multiple moving part 36. However, instead of the multiple moving part 36, a single moving part for abutting member 32 and a single moving part for abutting member 33, configured in the same way as the single moving part 35, may be provided. In this case, the single moving part provided for each abutting member 31 to 33 corresponds to an example of the "first single moving part", "second single moving part" and "third single moving part" of the present invention, respectively.

[0063] Furthermore, with the single movable part for abutting member 32 and the single movable part for abutting member 33 arranged in this way, it is not necessary to unify both the D2 direction and the D3 direction into the X2 direction, and at least one of the D2 direction and the D3 direction can be changed from the X2 direction.

[0064] (Second Implementation)

[0065] Figure 6 This is a schematic diagram illustrating the structure of a second embodiment of the centering device of the present invention. The second embodiment differs significantly from the first embodiment in that, instead of the multiple moving parts 36, it provides a single moving part 37 for the abutment member 32 and a single moving part 38 for the abutment member 33, configured in the same way as the single moving part 35, and points where both the D2 and D3 directions differ from the X2 direction. In this second embodiment, compared with... Figure 4 Similarly, for columns (a) and (b) and the research content based on their second and third movement amounts, the second and third movement amounts are set respectively. Other structures and operations are basically the same as in the first embodiment.

[0066] In this second embodiment, the distance from the center 21C of the rotating base 21 to the protruding portions 311, 321, and 331 is kept constant, and the abutting members 31 to 33 sequentially abut against the substrate S to clamp it. Thus, the center SC of the substrate S coincides with the center 21C of the rotating base 21. Therefore, centering is performed only through repetitive, minute movements of the abutting members 31 to 33, enabling centering with excellent productivity.

[0067] Figure 7 This diagram schematically illustrates the structure of a third embodiment of the centering device of the present invention. The third embodiment differs significantly from the first embodiment in the shape of the protruding portions 311, 321, and 331 of each abutment member 31-33. Specifically, in the first embodiment, the protruding portions 311, 321, and 331 have a sharp shape. Therefore, wear caused by contact with the substrate S is more severe, raising concerns about increased replacement frequency. Therefore, as... Figure 7 As shown, the protruding portions 311, 321, and 331 can also be precision-machined into a semi-disc shape. However, in the third embodiment, the contact position of the protruding portion 321 relative to the substrate S is displaced according to the amount of movement of the contact member 32 in the D2 direction. Furthermore, the contact position of the protruding portion 331 is also the same. Therefore, it cannot be directly applied... Figure 4 The second and third movement amounts in the third embodiment are calculated based on columns (a) and (b) and the research content of the second and third movement amounts based on them.

[0068] Therefore, in the third embodiment, after setting the reference distance r0 to 150.25 mm (=300.5 mm / 2) and the diameter of the protruding parts 311, 321, and 331 to 20 mm, a top view is created with distances equal to twice the distance (from the center 21C of the rotating base 21 to the protruding parts 311, 321, and 331), namely 300.5 mm, 300.2 mm, 300.1 mm, 300 mm, 299.9 mm, 299.8 mm, and 299.5 mm. Furthermore, in Figure 7 The figure shows a top view at a distance of 300.5 mm (see column (a)) and a top view at a distance of 300.2 mm (see column (b)). Other top views are omitted. Then, based on these top views, the amount of movement of the abutment member 31 and the amounts of movement of the abutment members 32 and 33 required to progressively shorten the distance from 300.5 mm are calculated. The results are summarized in... Figure 8 In addition, for reference, a graph showing the variation in the amount of movement of the abutting members 32 and 33 as determined in the first embodiment is also illustrated in this figure.

[0069] Figure 8 This is a graph showing the change in the amount of movement caused by the change in the distance from the center of the base to the protruding part in the third embodiment. The graph shows that in order to shorten the distance from the center 21C of the rotating base 21 to the protruding parts 311, 321, and 331 (the distance from the center of the base to the protruding part) while keeping the distance the same, it is necessary to appropriately change the amount of movement. Furthermore, the graph shows that the change in the amount of movement can be approximated by a linear function. Therefore, in the third embodiment, the linear function is pre-stored in the storage unit 92. On the other hand, during centering processing, the arithmetic processing unit 91 reads the linear function from the storage unit 92. Then, during centering processing, the arithmetic processing unit 91 obtains the amount of movement based on the linear function and controls the single moving part 35 and the multiple moving parts 36. Therefore, similar to the first embodiment, centering processing based on the contact members 31 to 33 can be performed effectively while keeping the distance from the center 21C of the rotating base 21 to the protruding parts 311, 321, and 331 the same. As a result, the same effects as the first embodiment can be achieved.

[0070] Furthermore, in the third embodiment, the protruding parts 311, 321, and 331 have a semi-disc shape, making them less prone to wear compared to the first embodiment, which has a sharp shape. Therefore, the replacement frequency of the contact parts 31-33 can be reduced, thus reducing the burden on operators and operating costs.

[0071] Furthermore, the present invention is not limited to the above-described embodiments, and various modifications can be made to the above content without departing from its spirit. For example, in the above embodiments, the clamping of the substrate S by the abutment members 31-33 is detected based on the load torque variation, i.e., the completion of the centering process, but the above detection can also be performed by other methods. For example, it is also possible to configure sensors such as force sensors or strain gauges to be provided on the single moving parts 35, 37, 38, and multiple moving parts 36, so that when the substrate S is clamped by the abutment members 31-33, the sensors detect stress or strain and output detection signals. In this case, the control unit 9 confirms that the abutment members 31-33 are clamping the substrate S based on the detection signals from the sensors.

[0072] In addition, in the third embodiment described above, the calculation processing unit 91 calculates the movement amount based on a linear function, but it can also be configured to summarize the changes in the movement amount in a data table and store them in the storage unit 92 instead of a linear function.

[0073] Furthermore, in the third embodiment described above, the protruding portions 321 and 331 are precision machined into a semi-disc shape, but they can also be precision machined into an inclined shape when viewed from the vertical direction. Thus, the structure in which the protruding portions 311, 321, and 331 are precision machined into a semi-disc shape, or into an inclined shape, can also be applied to the second embodiment.

[0074] Furthermore, in the above embodiments, the present invention is applied to a centering device equipped in a substrate processing apparatus 10 for performing oblique etching. However, the centering device of the present invention can be applied to a centering device and a centering method equipped in a substrate processing apparatus that performs processing while rotating a circular substrate.

[0075] The invention has been described above with reference to specific embodiments, but this description is not intended to be limited in meaning. As with other embodiments of the invention, those skilled in the art will understand various modifications of the disclosed embodiments when referring to this description. Therefore, the appended claims are considered to include such modifications or embodiments without departing from the true scope of the invention.

[0076] The present invention is applicable to a centering technique that aligns the center of a circular plate-shaped substrate placed on the upper surface of a substrate support with the center of the substrate support, and to a substrate processing apparatus that uses this technique to process the substrate.

Claims

1. A centering device for positioning a substrate by horizontally moving it on the upper surface of a substrate support such that the center of a circular plate-shaped substrate placed on the upper surface of the substrate support is aligned with the center of the substrate support. The centering device is characterized by having: The first abutting member is movable in a horizontal plane from a first reference position toward the center of the substrate support in a first horizontal direction, the first reference position being a reference distance from the center of the substrate support that is longer than the radius of the substrate. The second abutting member is movable within the horizontal plane from a second reference position in a second horizontal direction that is different from the direction toward the center of the substrate support and is close to the substrate and parallel to the virtual line. The second reference position is on the opposite side of the center of the substrate support, deviating from the virtual line extending from the center of the substrate support toward the first horizontal direction by a predetermined distance shorter than the radius of the substrate in a direction orthogonal to the virtual line, and moving away from the reference distance from the center of the substrate support. The third abutting member is movable within the horizontal plane from a third reference position in a third horizontal direction that is different from the direction toward the center of the substrate support and is close to the substrate and parallel to the virtual line. The third reference position is on the opposite side of the first abutting member relative to the center of the substrate support and on the opposite side of the second abutting member relative to the virtual line. It is separated from the virtual line by the predetermined distance and moves away from the reference distance from the center of the substrate support. A moving mechanism that causes the first abutting member, the second abutting member, and the third abutting member to move respectively in the first horizontal direction, the second horizontal direction, and the third horizontal direction; and The control unit controls the moving mechanism. The control unit repeatedly performs small movements, moving the first abutting member, the second abutting member, and the third abutting member by a first movement amount, a second movement amount, and a third movement amount, respectively, so that the distances of the first abutting member, the second abutting member, and the third abutting member from the center of the substrate support portion remain the same. If it is confirmed that the substrate is clamped by the first abutting member, the second abutting member, and the third abutting member, the micro-movement stops.

2. The centering device according to claim 1, characterized in that, The third reference position is symmetrical with respect to the virtual line and the second reference position line. The second movement amount and the third movement amount are the same value.

3. The centering device according to claim 2, characterized in that, The moving mechanism has: A single moving part that moves the first abutting member in the first horizontal direction; and Multiple movable parts, which cause the second abutting member and the third abutting member to move together in the second horizontal direction and the third horizontal direction, respectively.

4. The centering device according to claim 3, characterized in that, The single moving part has a motor for moving the first abutting member. The multiple moving parts include a motor for moving the second abutting member and the third abutting member. The control unit confirms the clamping of the first abutting member, the second abutting member, and the third abutting member on the substrate based on the load torque variation of at least one of the plurality of motors.

5. The centering device according to claim 1, characterized in that, The moving mechanism has: The first single moving part causes the first abutting member to move in the first horizontal direction; The second single moving part causes the second abutting member to move in the second horizontal direction; as well as The third single moving part causes the third abutting member to move in the third horizontal direction.

6. The centering device according to claim 5, characterized in that, The first single moving part has a motor for moving the first abutting member. The second single moving part has a motor for moving the second abutting member. The third single moving part has a motor for moving the third abutting member. The control unit confirms the clamping of the first abutting member, the second abutting member, and the third abutting member on the substrate based on the load torque variation of at least one of the plurality of motors.

7. The centering device according to claim 1, 2, 3 or 5, characterized in that, The device includes a sensor that detects stress or strain generated within the moving mechanism when the substrate is clamped by the first abutting member, the second abutting member, and the third abutting member, and outputs a detection signal. The control unit confirms the clamping of the substrate by the first abutting member, the second abutting member, and the third abutting member based on the detection signal from the sensor.

8. A centering method, characterized in that the center of a circular plate-shaped substrate is aligned with the center of a substrate support portion, wherein... have: In a horizontal plane, the process of placing the substrate on the upper surface of the substrate support with the first abutting member at a first reference position, the second abutting member at a second reference position, and the third abutting member at a third reference position, wherein the first reference position is located at a reference distance longer than the radius of the substrate from the center of the substrate support; the second reference position is located opposite the center of the substrate support to the first abutting member and deviates from the virtual line extending from the first reference position through the center of the substrate support by a predetermined distance shorter than the radius of the substrate in a direction orthogonal to the virtual line, and is located away from the reference distance from the center of the substrate support; the third reference position is located opposite the center of the substrate support to the first abutting member and opposite the virtual line to the second abutting member, is separated from the virtual line by the predetermined distance, and is located away from the reference distance from the center of the substrate support. The process of repeating the micro-movement is performed while the substrate is horizontally and freely placed on the upper surface of the substrate support. The first abutting member, the second abutting member, and the third abutting member are kept at the same distance from the center of the substrate support. The first abutting member moves from the first reference position toward a first horizontal direction toward the center of the substrate support. The second abutting member moves from the second reference position to a second horizontal direction that is different from the direction toward the center of the substrate support, closer to the substrate, and parallel to the virtual line by a second movement amount. The third abutting member moves from the third reference position to a third horizontal direction that is different from the direction toward the center of the substrate support, closer to the substrate, and parallel to the virtual line by a third movement amount. as well as If, during the repeated micro-movement process, it is confirmed that the substrate is clamped by the first abutting member, the second abutting member, and the third abutting member, the micro-movement process is stopped.

9. A substrate processing apparatus, characterized in that, have: A substrate support portion having an upper surface that supports a substrate in a horizontal position; The centering device according to any one of claims 1 to 6; The suction section exhausts air between the substrate positioned by the centering device and the substrate support section, thereby adsorbing and holding the substrate on the substrate support section. A rotation drive unit that causes the substrate support portion that holds the substrate to rotate about the center of the substrate support portion; as well as A processing liquid supply mechanism supplies processing liquid to the periphery of the substrate, which is integral with the substrate support and rotates around the center of the substrate support.

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