Substrate holding device and substrate processing device

Abstract

A substrate holding device and a substrate processing device are provided, which enable a substrate such as a wafer to perform a circular motion and stably hold the substrate while rotating the substrate around its axis. The substrate holding device (10) includes a plurality of rollers (11a, 11b), a plurality of motors (29a, 29b) that rotate the plurality of rollers (11a, 11b), a plurality of eccentric shafts (13a, 13b) arranged around a center axis (CP), and a plurality of actuators (18). The plurality of eccentric shafts (13a, 13b) are composed of a plurality of movable shafts (13b) and a plurality of reference shafts (13a). The plurality of actuators (18) are respectively linked to the plurality of movable shafts (13b), and the plurality of actuators (18) are configured to move the plurality of movable shafts (13b) in a direction approaching the plurality of reference shafts (13a) and a direction away from the plurality of reference shafts (13a).

Description

TECHNICAL FIELD

[0001] The present application relates to a substrate holding device that holds a substrate such as a wafer and rotates it. In addition, the present application relates to a substrate processing device that is provided with such a substrate holding device. BACKGROUND

[0002] In recent years, devices such as memory circuits, logic circuits, image sensors (for example, CMOS sensors), and the like are being more highly integrated. In the process of forming these devices, foreign matter such as fine particles, dust, and the like sometimes adheres to the devices. The foreign matter adhering to the devices can cause short circuits between wirings, malfunctions of circuits. Therefore, in order to improve the reliability of the devices, it is necessary to clean a wafer on which the devices are formed and remove foreign matter on the wafer.

[0003] On the back surface (bare silicon surface) of the wafer, foreign matter such as the above-mentioned fine particles, dust, and the like sometimes adheres. When such foreign matter adheres to the back surface of the wafer, the wafer can be separated from the reference surface of the stage of the exposure device, or the surface of the wafer can be tilted with respect to the reference surface of the stage, as a result of which, the pattern is shifted, the focal distance is shifted. In order to prevent such problems, it is necessary to remove foreign matter adhering to the back surface of the wafer.

[0004] PRIOR ART DOCUMENTS

[0005] PATENT DOCUMENTS

[0006] Patent Document 1: Japanese Patent Application Publication No. 2019-83224

[0007] PROBLEMS TO BE SOLVED BY THE INVENTION

[0008] Recently, the demand for a device that can more effectively process the entire surface of a substrate is increasing. Therefore, a substrate holding device that holds a substrate by a plurality of rollers linked to a plurality of eccentric shafts, rotates each eccentric shaft with its axis as the center in a state where the position of the eccentric shaft itself is stationary, thereby rotates the substrate with its axis as the center while making the substrate perform circular motion has been proposed (for example, Patent Document 1).

[0009] In a substrate processing device using such a substrate holding device, the rollers do not come into contact with the processing tool, and the processing tool can process the entire surface of the surface of the substrate including the outermost portion. In addition, the combination of such circular motion and rotation with the axis of the substrate as the center can increase the speed of each point on the surface of the substrate, as a result of which, the processing efficiency of the substrate can be improved.

[0010] In such a substrate holding apparatus, it is necessary to make the phases of the plurality of eccentric shafts coincide with each other. However, it is difficult to make the phases of the plurality of eccentric shafts correctly coincide with each other, and in the rotation of the substrate, sometimes vibration occurs in the eccentric shafts due to phase shift. In a case where vibration occurs in one of the plurality of eccentric shafts, sometimes the above vibration is transmitted to the other eccentric shafts via a common support plate that supports these eccentric shafts, and thus the holding of the substrate becomes unstable. SUMMARY

[0011] Therefore, an object of the present application is to provide a substrate holding apparatus that makes a substrate such as a wafer perform a circular motion and is capable of stably holding the substrate while rotating the substrate with its axis as the center. In addition, an object of the present application is to provide a substrate processing apparatus for processing the surface of a substrate using such a substrate holding apparatus.

[0012] In one embodiment, a substrate holding apparatus that rotates a substrate with its axis as the center while making the substrate perform a circular motion includes a plurality of rollers that are capable of contacting a peripheral portion of the substrate, a plurality of motors that rotate the plurality of rollers, a plurality of eccentric shafts that are arranged around a predetermined center axis, and a plurality of actuators. The plurality of eccentric shafts have a plurality of first shaft portions and a plurality of second shaft portions that are eccentric from the plurality of first shaft portions, respectively. The plurality of rollers are fixed to the plurality of second shaft portions, respectively. The plurality of first shaft portions are linked to the plurality of motors, respectively. The plurality of eccentric shafts are composed of a plurality of movable shafts and a plurality of reference shafts. The plurality of actuators are linked to the plurality of movable shafts, respectively. The plurality of actuators are configured to move the plurality of movable shafts in a direction in which the plurality of movable shafts approach the plurality of reference shafts and a direction in which the plurality of movable shafts move away from the plurality of reference shafts.

[0013] In one embodiment, the plurality of eccentric shafts further have a plurality of intermediate shaft portions that link the plurality of first shaft portions and the plurality of second shaft portions. The plurality of first shaft portions are fixed to the plurality of intermediate shaft portions, respectively. The plurality of second shaft portions are fixed to the plurality of intermediate shaft portions, respectively.

[0014] In one embodiment, the substrate holding apparatus further includes a motion control portion that rotates the plurality of motors at the same speed and at the same phase.

[0015] In one embodiment, the direction in which the plurality of movable shafts approach the plurality of reference shafts and the direction in which the plurality of movable shafts move away from the plurality of reference shafts are a direction toward the center axis and a direction away from the center axis.

[0016] In one embodiment, the plurality of actuators each include a piston, a housing disposed apart from the piston, and a diaphragm forming a pressure chamber between the piston and the housing.

[0017] In one embodiment, the diaphragm includes a central portion in contact with an end portion of the piston, an inner wall portion connected to the central portion and extending along a side surface of the piston, a turn-back portion connected to the inner wall portion and having a curved cross section, and an outer wall portion connected to the turn-back portion and located outside the inner wall portion.

[0018] In one embodiment, the substrate holding apparatus further includes at least one non-contact distance sensor that measures a movement distance of at least one of the plurality of movable shafts.

[0019] In one embodiment, the substrate holding apparatus further includes an operation control portion configured to determine whether the substrate holding apparatus is abnormal by comparing a measured value of the movement distance or an index value calculated from a plurality of measured values of the movement distance with a threshold value set in advance.

[0020] In one embodiment, the index value is an average value of positions of at least one of the plurality of movable shafts for one or more rotations of the plurality of rollers.

[0021] In one embodiment, the index value is a difference between a maximum value and a minimum value of positions of at least one of the plurality of movable shafts during one or more rotations of the plurality of rollers.

[0022] In one embodiment, a substrate holding apparatus rotates a substrate about an axis of the substrate while the substrate performs a circular motion, the substrate holding apparatus including a plurality of rollers contactable with a peripheral portion of the substrate, a plurality of motors that rotate the plurality of rollers, a plurality of eccentric shafts arranged around a predetermined central axis, and an actuator, the plurality of eccentric shafts including a plurality of first shaft portions and a plurality of second shaft portions eccentric from the plurality of first shaft portions, the plurality of rollers being fixed to the plurality of second shaft portions, the plurality of first shaft portions being linked to the plurality of motors, the plurality of eccentric shafts being composed of a movable shaft and a plurality of reference shafts, the actuator being linked to the movable shaft, the actuator being configured to move the movable shaft in a direction approaching the plurality of reference shafts and a direction away from the plurality of reference shafts, the actuator including a piston, a housing disposed apart from the piston, and a diaphragm forming a pressure chamber between the piston and the housing.

[0023] In one embodiment, the plurality of eccentric shafts further has a plurality of intermediate shaft portions connecting the plurality of first shaft portions and the plurality of second shaft portions, the plurality of first shaft portions are fixed to the plurality of intermediate shaft portions, respectively, and the plurality of second shaft portions are fixed to the plurality of intermediate shaft portions, respectively.

[0024] In one embodiment, the substrate holding device further has a movement control portion that rotates the plurality of motors at the same speed and at the same phase.

[0025] In one embodiment, the directions approaching the plurality of reference axes and the directions away from the plurality of reference axes are the directions toward the central axis and the directions away from the central axis.

[0026] In one embodiment, the partition wall film has a central portion in contact with an end portion of the piston, an inner wall portion connected to the central portion and extending along a side surface of the piston, a turn-back portion connected to the inner wall portion and having a curved cross section, and an outer wall portion connected to the turn-back portion and located outside the inner wall portion.

[0027] In one embodiment, the substrate holding device further has a non-contact distance sensor that measures a movement distance of the movable shaft.

[0028] In one embodiment, the substrate holding device further has a movement control portion configured to determine whether the substrate holding device is abnormal by comparing a measured value of the movement distance or an index value calculated from a plurality of measured values of the movement distance with a threshold value set in advance.

[0029] In one embodiment, the index value is an average value of positions of the movable shaft when the plurality of rollers rotate one or more revolutions.

[0030] In one embodiment, the index value is a difference between a maximum value and a minimum value of positions of the movable shaft during a period when the plurality of rollers rotate one or more revolutions.

[0031] In one embodiment, a substrate processing device is provided, including the substrate holding device, and a processing head that processes a first surface of a substrate by bringing a processing tool into contact with the first surface.

[0032] According to the present application, the plurality of movable shafts are connected to the plurality of actuators, respectively, and are not supported by a common support plate. According to such a structure, in the rotation of the substrate, even if vibration occurs in one movable shaft, the vibration can be prevented from being transmitted to other movable shafts. As a result, the substrate holding device can stably hold the substrate.

[0033] Furthermore, according to the present invention, since the actuator housing is positioned far from the piston, no sliding resistance is generated between the piston and the housing. As a result, the substrate holding device can stably hold the substrate without applying excessive load to the substrate. Attached Figure Description

[0034] Figure 1 This is a top view schematically illustrating one embodiment of the substrate holding device.

[0035] Figure 2 yes Figure 1 Side view of the substrate holding device shown.

[0036] Figure 3 yes Figure 1 The bottom view of the substrate holding device shown.

[0037] Figure 4 (a) to Figure 4 (d) is a schematic diagram illustrating the action of the substrate holding device accepting the wafer.

[0038] Figure 5 This is a schematic diagram illustrating one implementation of the actuator.

[0039] Figure 6 This is a cross-sectional view schematically illustrating one embodiment of the diaphragm membrane.

[0040] Figure 7 (a) is a diagram showing the state of the actuator when the pressure in the first pressure chamber is higher than the pressure in the second pressure chamber. Figure 7 (b) is a diagram showing the state of the actuator when the pressure in the second pressure chamber is higher than the pressure in the first pressure chamber.

[0041] Figure 8 This is a diagram illustrating an example of the position of a movable shaft when a wafer rotational malfunction occurs.

[0042] Figure 9 This is another example of the position of the movable shaft when a wafer rotational malfunction occurs.

[0043] Figure 10 This is a schematic diagram illustrating another implementation of the distance sensor.

[0044] Figure 11 It is a schematic representation of having a reference. Figures 1 to 10 A top view of one embodiment of the substrate processing apparatus of the substrate holding device described herein.

[0045] Figure 12 yes Figure 11 Side view of the substrate holding device shown.

[0046] Symbol Explanation

[0047] 1 first surface

[0048] 2 second surface

[0049] 10 substrate holding device

[0050] 11a, 11b roller

[0051] 13a, 13b eccentric shaft

[0052] 14a, 14b first shaft portion

[0053] 15a, 15b second shaft portion

[0054] 16a, 16b intermediate shaft portion

[0055] 17a, 17b counterweight

[0056] 18 actuator

[0057] 19 bearing

[0058] 20 base plate

[0059] 21 movable stage

[0060] 23 link member

[0061] 24 bearing

[0062] 26 linear guide

[0063] 27a, 27b motor support

[0064] 28a, 28b coupler

[0065] 29a, 29b motor

[0066] 31a, 31b wafer holding surface (substrate holding surface)

[0067] 40 operation control section

[0068] 51 piston

[0069] 52a, 52b housing

[0070] 53a, 53b housing main body

[0071] 54a, 54b cover

[0072] 55a, 55b partition wall film

[0073] 57a, 57b pressure chamber

[0074] 59a, 59b compressed gas flow path

[0075] 62a, 62b pressure regulator

[0076] 63a, 63b switching valve

[0077] 64 compressed gas supply source

[0078] 71a, 71b central portion

[0079] 72a, 72b inner wall portion

[0080] 73a, 73b turn-back portion

[0081] 74a, 74b outer wall portion

[0082] 75a, 75b thick wall portion

[0083] 80 distance sensor

[0084] 81 magnet

[0085] 84 sensor head

[0086] 85 focusing lens

[0087] 88 sensor target

[0088] 92A light projecting optical cable

[0089] 92B light receiving optical cable

[0090] 93 amplifier

[0091] 93a light source

[0092] 93b light intensity measurer

[0093] 94 distance calculator

[0094] 100 substrate processing apparatus

[0095] 200 polishing head

[0096] 201 processing tool DETAILED DESCRIPTION

[0097] Embodiments of the present application will be described below with reference to the accompanying drawings. Figure 1 is a plan view schematically showing one embodiment of a substrate holding apparatus, Figure 2 is Figure 1 is a side view of the substrate holding apparatus shown in Figure 3 is Figure 1A plan view of the substrate holding apparatus is shown. The substrate holding apparatus of the present embodiment is configured to hold a wafer W, which is an example of a substrate, while causing the wafer W to perform a circular motion, and to rotate the wafer W about its axis. The substrate holding apparatus 10 includes: a plurality of rollers 11a, 11b that can contact the peripheral portion of the wafer W; a plurality of motors 29a, 29b that rotate the plurality of rollers 11a, 11b; a plurality of eccentric shafts 13a, 13b that link the plurality of rollers 11a, 11b and the plurality of motors 29a, 29b; and an operation control section 40 that rotates the plurality of motors 29a, 29b at the same speed and at the same phase.

[0098] The operation control section 40 is configured by at least one computer. The operation control section 40 includes a storage device 40a and an arithmetic device 40b. The arithmetic device 40b includes a CPU (Central Processing Unit) or a GPU (Graphics Processing Unit), which performs arithmetic processing according to commands included in a program stored in the storage device 40a. The storage device 40a includes a main storage device (for example, a random access memory) that the arithmetic device 40b can access, and a secondary storage device (for example, a hard disk drive or a solid state drive) that stores data and programs.

[0099] The roller 11a has a wafer holding surface (substrate holding surface) 31a that holds the peripheral portion of the wafer W, and the roller 11b has a wafer holding surface (substrate holding surface) 31b that holds the peripheral portion of the wafer W. The roller 11a and the roller 11b have the same structure and the same size. The plurality of eccentric shafts 13a, 13b are arranged around a predetermined central axis CP of the substrate holding apparatus 10.

[0100] The substrate holding apparatus 10 of the present embodiment includes two rollers 11a, two rollers 11b, two eccentric shafts 13a, two eccentric shafts 13b, two motors 29a, and two motors 29b, but the number of these constituent elements is not limited by the present embodiment.

[0101] The plurality of eccentric shafts 13a each have a first shaft portion 14a, a second shaft portion 15a that is eccentric from the first shaft portion 14a, and an intermediate shaft portion 16a that connects the first shaft portion 14a and the second shaft portion 15a. At least two of the first shaft portion 14a, the second shaft portion 15a, and the intermediate shaft portion 16a can be a unitary structure. For example, the first shaft portion 14a and the intermediate shaft portion 16a can be a unitary structure. In another example, the entire first shaft portion 14a, the second shaft portion 15a, and the intermediate shaft portion 16a can be a unitary structure. Figure 2 Each eccentric shaft 13a shown has the shape of a crankshaft, but the shape of each eccentric shaft 13a is only required to be such that the second shaft portion 15a is eccentric from the first shaft portion 14a by a predetermined distance, and is not limited to the present embodiment.

[0102] The plurality of rollers 11a are fixed to one end of the plurality of second shaft portions 15a, and the other end of the plurality of second shaft portions 15a are fixed to the plurality of intermediate shaft portions 16a. One end of the plurality of first shaft portions 14a are connected to the plurality of motors 29a via the plurality of couplings 28a, and the other end of the plurality of first shaft portions 14a are fixed to the plurality of intermediate shaft portions 16a.

[0103] The plurality of eccentric shafts 13b each have a first shaft portion 14b, a second shaft portion 15b eccentric from the first shaft portion 14b, and an intermediate shaft portion 16b connecting the first shaft portion 14b and the second shaft portion 15b. At least two of the first shaft portion 14b, the second shaft portion 15b, and the intermediate shaft portion 16b can be integrally configured. For example, the first shaft portion 14b and the intermediate shaft portion 16b can be integrally configured. In another example, the entire of the first shaft portion 14b, the second shaft portion 15b, and the intermediate shaft portion 16b can be integrally configured. Figure 2 Each of the eccentric shafts 13b shown has the shape of a crankshaft, but the shape of each of the eccentric shafts 13b is not limited to the present embodiment as long as the second shaft portion 15b is eccentric from the first shaft portion 14b by a prescribed distance.

[0104] The plurality of rollers 11b are fixed to one end of the plurality of second shaft portions 15b, and the other end of the plurality of second shaft portions 15b are fixed to the plurality of intermediate shaft portions 16b. One end of the plurality of first shaft portions 14b are connected to the plurality of motors 29b via the plurality of couplings 28b, and the other end of the plurality of first shaft portions 14b are fixed to the plurality of intermediate shaft portions 16b.

[0105] The motor 29a rotates the eccentric shaft 13a with the first shaft portion 14a as the center, and the motor 29b rotates the eccentric shaft 13b with the first shaft portion 14b as the center. The motors 29a, 29b are connected to the operation control portion 40.

[0106] The second shaft portion 15a of the eccentric shaft 13a is eccentric from the first shaft portion 14a by a distance e. Therefore, when the motor 29a operates, the roller 11a rotates with the second shaft portion 15a as the center while performing a circular motion with a radius of e. The axis of the roller 11a coincides with the axis of the second shaft portion 15a. That is, the roller 11a rotates with its axis as the center while performing a circular motion with a radius of e around the axis of the first shaft portion 14a. When the roller 11a rotates one revolution with the axis of the first shaft portion 14a as the center, the roller 11a rotates one revolution with the axis of the roller 11a as the center.

[0107] Similarly, the second shaft portion 15b of the eccentric shaft 13b is eccentric from the first shaft portion 14b by an eccentric distance e. Therefore, when the motor 29b is operated, the roller 11b rotates with the second shaft portion 15b as the center and performs a circular motion with a radius of e. The shaft center of the roller 11b coincides with the shaft center of the second shaft portion 15b. That is, the roller 11b rotates with its shaft center as the center and performs a circular motion with a radius of e around the shaft center of the first shaft portion 14b. When the roller 11b rotates one revolution with the shaft center of the first shaft portion 14b as the center, the roller 11b rotates one revolution with the shaft center of the roller 11b as the center. In the present specification, the circular motion is defined as a motion in which an object moves on a circular track.

[0108] The operations of the motors 29a, 29b are controlled by the operation control section 40. As described above, the operation control section 40 rotates all the motors 29a, 29b at the same speed and at the same phase. More specifically, the operation control section 40 issues an instruction to the motors 29a, 29b to start all the motors 29a, 29b at the same time and to rotate all the motors 29a, 29b in the same direction. Furthermore, the operation control section 40 synchronizes the respective rotational speeds and phases in the operations of the motors 29a, 29b.

[0109] As a result, all the eccentric shafts 13a, 13b rotate with the shaft centers of the first shaft portions 14a, 14b as the center, at the same rotational speed and at the same phase, in the same direction. All the rollers 11a, 11b rotate with their shaft centers as the center, in the same direction, at the same rotational speed and at the same phase, and perform a circular motion with the shaft centers of the first shaft portions 14a, 14b as the center. Therefore, when the wafer W is held by the rollers 11a, 11b, the wafer W rotates with its shaft center as the center and performs a circular motion with a radius of e by the operation control section 40 operating the motors 29a, 29b.

[0110] Thus, the substrate holding device 10 can rotate the wafer W with its shaft center as the center and perform a circular motion with a simple structure. The combination of the circular motion and the rotation with the shaft center of the wafer W as the center can increase the speed of each point on the surface of the wafer W. Therefore, when a processing head is pressed against the surface of the wafer W as described later, the relative speed of the processing head to the surface of the wafer W increases, and thus the processing speed of the wafer W can be increased.

[0111] The counterweights 17a, 17b are fixed to the eccentric shafts 13a, 13b, respectively. More specifically, the counterweights 17a, 17b are fixed to the intermediate shaft portions 16a, 16b, respectively. The counterweight 17a and the roller 11a are symmetrically arranged with respect to the first shaft portion 14a. The weight of the counterweight 17a is a weight that cancels the centrifugal force acting on the counterweight 17a from the centrifugal force generated in the radial direction from the first shaft portion 14a toward the roller 11a when the eccentric shaft 13a rotates with the first shaft portion 14a as the center.

[0112] Similarly, the counterweight 17b and roller 11b are arranged symmetrically about the first shaft portion 14b. The weight of the counterweight 17b is the weight that cancels out the centrifugal force generated in the radial direction from the first shaft portion 14b toward the roller 11b when the eccentric shaft 13b rotates about the first shaft portion 14b. When the eccentric shafts 13a and 13b rotate, such counterweights 17a and 17b can prevent vibration of the eccentric shafts 13a and 13b caused by weight imbalance.

[0113] The substrate holding device 10 further includes: a base plate 20; a plurality of linear guide members 26 fixed to the lower surface of the base plate 20; a plurality of movable stages 21 supported by the plurality of linear guide members 26; and a plurality of actuators 18 connected to the plurality of movable stages 21. The linear guide members 26 restrict the movement of the movable stages 21 to linear movement in a direction parallel to the lower surface of the base plate 20.

[0114] Each movable stage 21 has a bearing 24 that supports the eccentric shaft 13b for rotation and a connecting member 23 that connects to the actuator 18. Multiple actuators 18 are connected to multiple eccentric shafts 13b via multiple movable stages 21. Multiple movable stages 21, each containing multiple bearings 24, and multiple eccentric shafts 13b are integrally moved independently via multiple actuators 18.

[0115] The actuator 18 is fixed to the lower surface of the base plate 20. The operation of the actuator 18 is controlled by the motion control unit 40. The motion control unit 40 enables the actuator 18 to operate independently. The actuator 18 is configured to move the movable stage 21 parallel to the base plate 20.

[0116] An eccentric shaft 13a extends through the base plate 20. A roller 11a is positioned above the base plate 20, and a motor 29a is positioned below the base plate 20. The eccentric shaft 13a is supported by a bearing 19 held by the base plate 20, enabling it to rotate. The positions of these eccentric shafts 13a are fixed. The motor 29a is fixed to the base plate 20 via a motor support 27a. More specifically, the motor support 27a is fixed to the lower surface of the base plate 20, and the motor 29a is fixed to the motor support 27a.

[0117] An eccentric shaft 13b extends through the movable stage 21 and the base plate 20. A roller 11b is positioned above the base plate 20, and a motor 29b is positioned below the base plate 20. The eccentric shaft 13b is supported by a bearing 24 of the movable stage 21, enabling it to rotate. The motor 29b is fixed to the movable stage 21 via a motor support 27b. More specifically, the motor support 27b is fixed to the lower surface of the movable stage 21, and the motor 29b is fixed to the motor support 27b.

[0118] According to the above structure, eccentric shaft 13a is a reference shaft that is immovable relative to base plate 20, and eccentric shaft 13b is a movable shaft that is movable relative to base plate 20. In the following description, eccentric shaft 13a is sometimes referred to as reference shaft 13a, and eccentric shaft 13b is sometimes referred to as movable shaft 13b. Actuator 18 is connected to movable shaft 13b via movable stage 21. Movable stage 21 has a bearing 24 that supports movable shaft 13b for rotation and a connecting member 23 that is connected to actuator 18. Therefore, movable stage 21 connects actuator 18 and movable shaft 13b.

[0119] The actuator 18 is capable of moving the movable shaft 13b parallel to the base plate 20 via the movable stage 21. Specifically, the plurality of actuators 18 are configured to move the plurality of movable shafts 13b in directions approaching and away from the plurality of reference shafts 13a. When two movable shafts 13b move in directions approaching the two reference shafts 13a, the wafer W is held by the two rollers 11a and two rollers 11b. When the two movable shafts 13b move in directions away from the two reference shafts 13a, the wafer W is released from the two rollers 11a and two rollers 11b.

[0120] like Figure 3 As shown, in this embodiment, the actuator 18 and the linear guide 26 are arranged toward the central axis CP of the substrate holding device 10. The actuator 18 causes the movable shaft 13b to... Figure 3 The arrow moves in the direction of the axis. In this embodiment, the direction approaching the plurality of reference axes 13a and the direction moving away from the plurality of reference axes 13a are the direction toward the central axis CP and the direction moving away from the central axis CP, respectively. When the movable axis 13b is moved in the direction toward the central axis CP, the roller 11b can hold the wafer W with a holding force toward the center of the wafer W. According to the structure of this embodiment, the substrate holding device 10 can effectively hold the wafer W with minimal force. In one embodiment, the plurality of actuators 18 and the plurality of linear guides 26 may also be configured toward each of the plurality of reference axes 13a.

[0121] Figure 4 (a) to Figure 4 (d) is a schematic diagram illustrating the action of the substrate holding device 10 accepting the wafer W. Figure 4 As shown in (a), before receiving the chip W, each actuator 18 (refer to) is activated. Figure 2 and Figure 3 The rollers 11a and 11b move away from the central axis CP during operation. At this time, rollers 11a and 11b are eccentrically outward.

[0122] Next, as Figure 4 As shown in (b), the wafer W is transported to the substrate holding device 10 by a transport device (not shown). Furthermore, as... Figure 4As shown in (c), with the wafer W positioned between rollers 11a and 11b, the reference axis 13a is rotated 180 degrees, causing each roller 11a to become eccentrically inward. Then, as... Figure 4 As shown in (d), each actuator 18 is activated, thereby moving each roller 11b and each movable shaft 13b toward each reference shaft 13a until each roller 11b contacts the wafer W.

[0123] Thus, the periphery of the wafer W is held by the wafer holding surface 31a of roller 11a and the wafer holding surface 31b of roller 11b. When the wafer W is removed from the substrate holding device 10, Figure 4 (a) to Figure 4 The process shown in (d) is performed in reverse order.

[0124] In existing substrate holding devices (for example, see Patent Document 1), multiple movable shafts are supported by a support plate, and the multiple movable shafts are moved integrally with the support plate by an actuator connected to the support plate, thereby holding the substrate. With such a structure, if vibration occurs in one of the multiple movable shafts due to phase deviation or the like, the vibration propagates to the other movable shafts, thereby making the holding of the substrate unstable.

[0125] In contrast, in the above embodiment, the two movable shafts 13b are each supported by two movable stages 21, and then connected to two actuators 18 respectively. With this structure, even if one movable shaft 13b vibrates during the rotation of the wafer W, the vibration can be prevented from propagating to the other movable shafts 13b. As a result, the substrate holding device 10 can stably hold the wafer W.

[0126] Figure 5 This is a schematic diagram illustrating one embodiment of the actuator 18. Each actuator 18 includes: a piston 51 disposed along the length of the actuator 18; housings 52a and 52b disposed outside the piston 51; and partition membranes (diaphragms) 55a and 55b forming pressure chambers 57a and 57b between the piston 51 and the housings 52a and 52b. The piston 51 is capable of pressing against the piston. Figure 5 The actuator moves in the direction indicated by the arrow (the length direction of the actuator 18). Housings 52a and 52b are positioned away from the piston 51. Housing 52a is positioned to surround one end of the piston 51, and housing 52b is positioned to surround the other end of the piston 51.

[0127] A connecting member 23, including a movable stage 21, is connected to the piston 51, and the piston 51 is supported by the connecting member 23. The movable stage 21, including the connecting member 23, can move integrally with the piston 51. Figure 5The movable stage 21 moves in the direction indicated by the arrow. More specifically, the movable stage 21 is configured to move integrally with the piston 51 in a direction approaching the reference axis 13a and in a direction away from the reference axis 13a. In this embodiment, the actuator 18 is positioned toward the central axis CP of the substrate holding device 10 (see reference 10). Figure 3 Therefore, the moving directions of piston 51 and movable stage 21 are towards the central axis CP and away from the central axis CP.

[0128] Housings 52a and 52b include housing bodies 53a and 53b arranged to surround the sides of piston 51, and covers 54a and 54b fixed to the housing bodies 53a and 53b. The edge of the diaphragm 55a is sandwiched between the housing body 53a and the cover 54a. Similarly, the edge of the diaphragm 55b is sandwiched between the housing body 53b and the cover 54b.

[0129] Pressure chamber 57a is formed by the inner surfaces of the partition membrane 55a and the housing 52a. Similarly, pressure chamber 57b is formed by the inner surfaces of the partition membrane 55b and the housing 52b. More specifically, pressure chamber 57a is formed by the inner surfaces of the partition membrane 55a and the cover 54a, and pressure chamber 57b is formed by the inner surfaces of the partition membrane 55b and the cover 54b. The partition membranes 55a and 55b have the same structure. In this embodiment, the housings 52a and 52b have the same structure, but they may also have different structures.

[0130] Compressed gas flow paths 59a and 59b are formed in the covers 54a and 54b of the housings 52a and 52b. The compressed gas flow paths 59a and 59b are connected to the compressed gas supply source 64 via pressure regulators 62a and 62b and switching valves 63a and 63b. Pressure chambers 57a and 57b are connected to pressure regulators 62a and 62b via the compressed gas flow paths 59a and 59b.

[0131] When piston 51 is moved, switching valves 63a and 63b are operated, thereby connecting pressure chambers 57a and 57b to the compressed gas supply source 64. In this embodiment, switching valves 63a and 63b are connected to the operation control unit 40. Switching valves 63a and 63b are valves that selectively connect pressure chambers 57a and 57b to the compressed gas supply source 64 or the atmosphere. Three-way valves can be used as switching valves 63a and 63b.

[0132] Compressed gases, such as compressed air, are supplied from a compressed gas supply source 64 through compressed gas flow paths 59a and 59b to pressure chambers 57a and 57b. Examples of the compressed gas supply source 64 include pumps or compressed gas supply lines pre-installed in the factory for application. The pressure of the compressed gas in pressure chambers 57a and 57b is controlled by pressure regulators 62a and 62b. In this embodiment, pressure regulators 62a and 62b are electro-pneumatic regulators. In this embodiment, pressure regulators 62a and 62b are connected to the operation control unit 40. In one embodiment, pressure regulators 62a and 62b may also be manually operated pressure regulators. In this case, pressure regulators 62a and 62b are not connected to the operation control unit 40.

[0133] The motion control unit 40 sends a predetermined set pressure value to the pressure regulators 62a and 62b, and the pressure regulators 62a and 62b control the pressure of the compressed gas in the pressure chambers 57a and 57b according to the aforementioned set pressure value. Examples of such pressure regulators 62a and 62b include electro-pneumatic regulators and mechanical regulators. In one embodiment, the pressure regulator 62b may be an electro-pneumatic regulator, and the pressure regulator 62a may be a mechanical regulator. When the pressure regulator 62a is a mechanical regulator, the pressure regulator 62a is not connected to the motion control unit 40.

[0134] Piston 51 moves according to the pressure difference between pressure chamber 57a and pressure chamber 57b. When the pressure in pressure chamber 57a is higher than the pressure in pressure chamber 57b, piston 51 moves in a direction away from reference axis 13a (refer to...). Figure 3 When the pressure in pressure chamber 57b is higher than the pressure in pressure chamber 57a, piston 51 moves towards the reference axis 13a (refer to...). Figure 3 )move.

[0135] In this embodiment, when the piston 51 is moved, compressed gas is introduced into both pressure chambers 57a and 57b, and the pressure of the compressed gas inside either pressure chamber 57a or pressure chamber 57b is higher than the pressure of the compressed gas inside the other. In one embodiment, when the piston 51 is moved, compressed gas may be introduced into only either pressure chamber 57a or pressure chamber 57b, and the other may be connected to the atmosphere.

[0136] Figure 6This is a schematic cross-sectional view illustrating one embodiment of the diaphragm membranes 55a and 55b. The diaphragm membrane 55a has: a central portion 71a that contacts one end of the piston 51; an inner wall portion 72a connected to the central portion 71a and extending along the side of the piston 51; a folded-back portion 73a connected to the inner wall portion 72a and having a curved cross-section; and an outer wall portion 74a connected to the folded-back portion 73a and located outside the inner wall portion 72a. The diaphragm membrane 55a contacts one end of the piston 51. When compressed gas is introduced into the pressure chamber 57a, the outer wall portion 74a contacts the inner surface of the housing body 53a.

[0137] In this embodiment, the central portion 71a is circular. The inner wall portion 72a and the outer wall portion 74a are cylindrical, with the inner wall portion 72a contacting the side of the piston 51. The outer wall portion 74a is arranged to surround the inner wall portion 72a.

[0138] Similarly, the diaphragm 55b has: a central portion 71b that contacts the other end of the piston 51; an inner wall portion 72b connected to the central portion 71b and extending along the side of the piston 51; a fold-back portion 73b connected to the inner wall portion 72b and having a curved cross-section; and an outer wall portion 74b connected to the fold-back portion 73b and located outside the inner wall portion 72b. The diaphragm 55b contacts the other end of the piston 51. When compressed gas is introduced into the pressure chamber 57b, the outer wall portion 74b contacts the inner surface of the housing body 53b.

[0139] In this embodiment, the central portion 71b is circular. The inner wall portion 72b and the outer wall portion 74b are cylindrical, with the inner wall portion 72b contacting the side of the piston 51. The outer wall portion 74b is arranged to surround the inner wall portion 72b.

[0140] The diaphragm membranes 55a and 55b are in contact with the piston 51, but are not fixed to it. The thick-walled portion 75a forming the edge of the diaphragm 55a is sandwiched between the housing body 53a and the cover 54a. Similarly, the thick-walled portion 75b forming the edge of the diaphragm 55b is sandwiched between the housing body 53b and the cover 54b. The diaphragm membranes 55a and 55b are formed of a flexible material. Examples of materials constituting the diaphragm membranes 55a and 55b include neoprene rubber, fluororubber, and silicone rubber. Neoprene rubber, which has high resistance to flexural fatigue, is preferred.

[0141] Figure 7 (a) is a diagram showing the state of actuator 18 when the pressure in pressure chamber 57a (first pressure chamber 57a) is higher than the pressure in pressure chamber 57b (second pressure chamber 57b). Figure 7(b) is a diagram showing the state of actuator 18 when the pressure in pressure chamber 57b is higher than the pressure in pressure chamber 57a.

[0142] like Figure 7 As shown in (a), when the pressure in pressure chamber 57a is higher than the pressure in pressure chamber 57b, a force is applied to piston 51 in the direction toward pressure chamber 57b. As a result, the diaphragm membranes 55a and 55b deform, and piston 51, movable stage 21, and movable shaft 13b move integrally in a direction away from reference axis 13a (see reference). Figure 3 The reversing portion 73a moves. At this time, while maintaining its shape, a portion of the inner wall portion 72a becomes part of the reversing portion 73a, and a portion of the reversing portion 73a becomes part of the outer wall portion 74a. At the same time, the reversing portion 73b maintains its shape, a portion of the outer wall portion 74b becomes part of the reversing portion 73b, and a portion of the reversing portion 73b becomes part of the inner wall portion 72b.

[0143] like Figure 7 As shown in (b), when the pressure in pressure chamber 57b is higher than the pressure in pressure chamber 57a, a force is applied to piston 51 in the direction of pressure chamber 57a. As a result, the diaphragm 55b deforms, and piston 51, movable stage 21, and movable shaft 13b move integrally in a direction approaching reference axis 13a (see reference). Figure 3 The reversing portion 73b maintains its shape, and a portion of the inner wall portion 72b becomes part of the reversing portion 73b, while a portion of the reversing portion 73b becomes part of the outer wall portion 74b. Simultaneously, the reversing portion 73a maintains its shape, and a portion of the outer wall portion 74a becomes part of the reversing portion 73a, while a portion of the reversing portion 73a becomes part of the inner wall portion 72a.

[0144] Through the movement of the diaphragm membranes 55a and 55b, the piston 51 can move smoothly with almost no reaction force from the diaphragm membranes 55a and 55b. As with a conventional cylinder, when the piston contacts the housing, vibrations occur during the rotation of the wafer, generating sliding resistance between the piston and the housing. This sliding resistance imposes an excessive load on the rotating wafer, becoming a major cause of unstable wafer holding. In this embodiment, since the housings 52a and 52b are positioned away from the piston 51, no sliding resistance is generated between the piston 51 and the housings 52a and 52b. As a result, the substrate holding device 10 can stably hold the wafer W without applying excessive load to the wafer W.

[0145] like Figure 5As shown, the substrate holding device 10 includes a non-contact distance sensor 80 for measuring the movement distance of the movable shaft 13b. The distance sensor 80 is disposed outside the actuator 18 and near the actuator 18 and the movable stage 21. A magnet 81 is fixed to the connecting member 23 of the movable stage 21, and the distance sensor 80 is opposite to the magnet 81. In this embodiment, the distance sensor 80 is a magnetic sensor capable of measuring the relative movement distance of the magnet 81 relative to the distance sensor 80.

[0146] The position of the distance sensor 80 is fixed. On the other hand, the movable stage 21, piston 51, and movable shaft 13b can move as a unit. Therefore, when the movable shaft 13b moves towards the reference axis 13a and away from the reference axis 13a, the relative position of the magnet 81 fixed to the movable stage 21 with respect to the distance sensor 80 changes. The distance the magnet 81 moves corresponds to the distance the movable shaft 13b moves. Therefore, the distance sensor 80 can measure the distance the movable shaft 13b moves. The distance the movable shaft 13b moves is its relative position to a predetermined reference position. Hereinafter, the relative position of the movable shaft 13b with respect to a predetermined reference position will sometimes be referred to simply as the position of the movable shaft 13b.

[0147] Distance sensor 80 is connected to motion control unit 40, and distance sensor 80 sends the measured value of the movement distance of movable shaft 13b (the measured value of the position of movable shaft 13b) to motion control unit 40. Motion control unit 40 determines whether substrate holding device 10 correctly holds wafer W (whether substrate holding device 10 malfunctions) by comparing the measured value of the movement distance of movable shaft 13b (the position of movable shaft 13b) with a preset threshold. In one embodiment, motion control unit 40 may also issue an alarm signal when the measured value of the movement distance (the position of movable shaft 13b) is greater than or less than the threshold. Furthermore, in one embodiment, motion control unit 40 may also determine whether substrate holding device 10 correctly holds wafer W (whether substrate holding device 10 malfunctions) by comparing an index value calculated based on multiple measured values ​​of the movement distance (multiple measured values ​​of the position of movable shaft 13b) with a preset threshold. Furthermore, in one embodiment, motion control unit 40 may also issue an alarm signal when the index value is greater than or less than the threshold. As examples of the aforementioned index values, the average position of the movable shaft 13b when the roller 11b rotates more than one revolution can be given, as well as the difference between the maximum and minimum positions of the movable shaft 13b during the period when the roller 11b rotates more than one revolution (the amplitude of the position of the movable shaft 13b).

[0148] The reason why the measured value of the moving distance of the movable shaft 13b when it moves in a direction close to the reference shaft 13a is less than the threshold can be considered as the wafer W not being properly held in the substrate holding device 10. The reason why the measured value of the moving distance is greater than the threshold can be considered as the wafer W being broken or detached (wafer W detachment, gripping loss).

[0149] Furthermore, in one embodiment, a first threshold and a second threshold smaller than the first threshold may be set for the measured value of the movement distance of the movable shaft 13b. Specifically, the motion control unit 40 is configured to issue an alarm signal when the measured value of the movement distance is greater than the first threshold, and to issue an alarm signal when the measured value of the movement distance is less than the second threshold. The range from the second threshold to the first threshold is the range of movement distance of the movable shaft 13b required for the rollers 11a and 11b to correctly hold the wafer W.

[0150] When the movable shaft 13b vibrates during the rotation of the wafer W, the position of the movable shaft 13b (a measured value of the moving distance of the movable shaft 13b) changes with the vibration. Therefore, the motion control unit 40 can detect the vibration of the movable shaft 13b based on the change in the position of the movable shaft 13b during the rotation of the wafer W (the change in the measured value of the moving distance of the movable shaft 13b). The motion control unit 40 can detect abnormalities in the rotation of the wafer W when the substrate holding device 10 holds and rotates the wafer W based on the vibration of the movable shaft 13b. As causes of abnormalities in the rotation of the wafer W, wear, deformation, breakage, dimensional defects, or phase shifts in the rotation of the wafer holding surfaces 31a and 31b of the rollers 11a and 11b can be considered.

[0151] In one embodiment, the motion control unit 40 may also compare the amplitude of the measured value of the movement distance of the movable shaft 13b (position of the movable shaft 13b) with a preset threshold, and determine that vibration has occurred in the movable shaft 13b when the amplitude is greater than the threshold. The motion control unit 40 may also issue an alarm signal when the amplitude is greater than the threshold.

[0152] Figure 8 This diagram illustrates an example of the position of the movable shaft 13b when an abnormal rotation of the wafer W occurs. The horizontal axis of the diagram represents the rotation angle of the roller 11b, and the vertical axis represents the position of the movable shaft 13b. Figure 8 In the actuator 18, the closer the movable shaft 13b is to the reference shaft 13a, the smaller the position value of the movable shaft 13b; conversely, the farther the movable shaft 13b is from the reference shaft 13a, the larger the position value of the movable shaft 13b. A position of 0° for the movable shaft 13b means that within the movable range of the actuator 18, the movable shaft 13b is closest to the reference shaft 13a. A rotation angle of 0° for the roller 11b refers to a predetermined reference angle for the roller 11b.Figure 8 In the example shown, when an abnormal rotation of the wafer W occurs, the movable shaft 13b vibrates significantly, and its position changes drastically. At this time, the amplitude of the positional fluctuation of the movable shaft 13b is greater than a predetermined amplitude threshold. As the occurrence... Figure 8 The reason for the change in the position of the movable shaft 13b shown can be considered as wear, deformation, breakage, dimensional defects, or rotational phase shift of the wafer holding surfaces 31a and 31b of the rollers 11a and 11b.

[0153] The motion control unit 40 compares the amplitude of the position of the movable shaft 13b (a measured value of the movement distance of the movable shaft 13b) with a predetermined amplitude threshold. When the amplitude of the position of the movable shaft 13b is greater than the amplitude threshold, it determines that an abnormal rotation of the wafer W has occurred. In this specification, the amplitude of the position of the movable shaft 13b is defined as the vibration amplitude of the movable shaft 13b. Figure 8 In the example shown, the amplitude of the movable shaft 13b is the difference between the maximum value and the minimum value of the position of the movable shaft 13b during the period when the roller 11b rotates more than one revolution. In one embodiment, the motion control unit 40 may also compare the amplitude of the position of the movable shaft 13b (a measured value of the movement distance of the movable shaft 13b) during the time from the first rotation time to the second rotation time of the roller 11b with a predetermined amplitude threshold.

[0154] Furthermore, in one embodiment, the motion control unit 40 may also issue an alarm signal when the amplitude at the position of the movable shaft 13b is greater than an amplitude threshold. Furthermore, in one embodiment, the motion control unit 40 may also issue a command to the motors 29a and 29b to stop their operation when the amplitude at the position of the movable shaft 13b is greater than an amplitude threshold.

[0155] Figure 9 This diagram illustrates another example of the position of the movable shaft 13b when an abnormal rotation of the wafer W occurs. Details of this embodiment, unless otherwise specified, are referenced. Figure 8 The implementation methods described are the same, therefore repeated descriptions are omitted. Figure 9 In the example shown, the average position of the movable shaft 13b when roller 11b rotates more than one revolution is smaller than the initial average and the predetermined lower threshold. In this embodiment, the initial average is the average position (measured value) of the movable shaft when rollers 11a and 11b are not in use (not worn). Figure 9 The reason for the positional variation of the movable shaft 13b shown can be attributed to wear, deformation, damage, or dimensional defects of the wafer holding surfaces 31a and 31b of the rollers 11a and 11b. Figure 9The dashed line L1 represents the average position of the movable shaft 13b during the rotation of the wafer W when the wafer holding surfaces 31a and 31b are damaged.

[0156] The motion control unit 40 compares the average position of the movable shaft 13b (the average value of the measured distance of movement of the movable shaft 13b) when the roller 11b rotates more than one revolution with a predetermined lower threshold. When the average position of the movable shaft 13b is less than the lower threshold, it determines that a rotational abnormality of the wafer W has occurred. In one embodiment, the motion control unit 40 may also compare the average position of the movable shaft 13b (the average value of the measured distance of movement of the movable shaft 13b) when the roller 11b rotates more than one revolution with a predetermined upper threshold. When the average position of the movable shaft 13b is greater than the upper threshold, it determines that a rotational abnormality of the wafer W has occurred. As an example of why the average position of the movable shaft 13b becomes greater than the upper threshold, it can be considered that the wafer W is not properly held in the substrate holding device 10. Based on the above-described reference position setting of the movable shaft 13b, due to wear, deformation, damage, or dimensional defects of the wafer holding surfaces 31a, 31b of the rollers 11a, 11b, the average position of the movable shaft 13b may sometimes be greater than the upper threshold.

[0157] In one embodiment, the motion control unit 40 may also issue an alarm signal when the average position of the movable shaft 13b during more than one rotation of the roller 11b is less than a lower threshold (or, the average position of the movable shaft 13b during more than one rotation of the roller 11b is greater than an upper threshold). Furthermore, in one embodiment, the motion control unit 40 may also issue a command to the motors 29a and 29b to stop their operation when the average position of the movable shaft 13b during more than one rotation of the roller 11b is less than the lower threshold (or, the average position of the movable shaft 13b during more than one rotation of the roller 11b is greater than the upper threshold). As an example of an alarm signal, a signal prompting the operator to replace the rollers 11a and 11b can be given.

[0158] According to reference Figure 9 In the described embodiment, regardless of whether the wafer holding surfaces 31a and 31b of rollers 11a and 11b are worn evenly or unevenly, the motion control unit 40 can detect any abnormalities in rollers 11a and 11b. (See also...) Figure 8 Description of implementation methods and references Figure 9 The described implementation methods can also be combined. For example, the motion control unit 40 can also determine an abnormality and issue an alarm signal when the amplitude of the position of the movable shaft 13b is greater than the amplitude threshold, or when the average value of the position of the movable shaft 13b when the roller 11b rotates more than one revolution is less than the lower limit threshold.

[0159] The non-contact distance sensor 80 can accurately measure the movement distance of the movable shaft 13b even when the movable shaft 13b vibrates, unaffected by the vibration. In this embodiment, multiple non-contact distance sensors 80 are provided to measure the movement distance of multiple movable shafts 13b respectively. In one embodiment, a single non-contact distance sensor 80 may also be provided to measure the movement distance of one of the multiple movable shafts 13b.

[0160] In one implementation, such as Figure 10 As shown, the distance sensor 80 can also be a non-contact optical sensor. Details of this embodiment, unless otherwise specified, are available in the references. Figure 5 , Figure 8 as well as Figure 9 The described implementation is the same, so repeated descriptions are omitted. The distance sensor 80 of this embodiment includes: a sensor head 84 having a light-emitting portion and a light-receiving portion (not shown) at its top; a focusing lens 85 for focusing light emitted from the sensor head 84; an amplifier 93 connected to the sensor head 84 via a light-emitting optical cable 92A and a light-receiving optical cable 92B; and a distance calculator 94 electrically connected to the amplifier 93. The focusing lens 85 is mounted at the top of the sensor head 84.

[0161] The sensor head 84 is fixed to the outside of the actuator 18, with its tip facing the movable stage 21. More specifically, in this embodiment, a sensor target 88 is mounted on the movable stage 21, with the tip of the sensor head 84 facing the sensor target 88. The sensor target 88 has the property of reflecting light. As an example of the sensor target 88, a component made of ceramic or metal can be cited. The amplifier 93 and the distance calculator 94 are located away from the actuator 18.

[0162] Amplifier 93 includes a light source 93a that emits light and a light intensity meter 93b that measures the intensity of reflected light. Light emitted from the light source 93a of amplifier 93 is transmitted to sensor head 84 via optical fiber 92A. Sensor head 84 guides light toward sensor target 88 via focusing lens 85 and receives reflected light from sensor target 88. The reflected light is transmitted to amplifier 93 via receiving optical fiber 92B. Light intensity meter 93b of amplifier 93 measures the intensity of reflected light. Amplifier 93 sends the measured value of the intensity of reflected light to distance calculator 94, which converts the measured value of the intensity of reflected light into distance. The distance obtained by distance calculator 94 is the movement distance of movable shaft 13b. With this structure, distance sensor 80 of this embodiment can measure the movement distance of movable shaft 13b. Distance calculator 94 is connected to motion control unit 40 and sends the measured value of the movement distance of movable shaft 13b to motion control unit 40. In one embodiment, distance sensor 80 may also lack focusing lens 85. The sensor head 84 can also guide light toward the sensor target 88 without passing through the focusing lens 85, and receive reflected light from the sensor target 88 without passing through the focusing lens 85.

[0163] As described above, among the components constituting the distance sensor 80, only the sensor head 84 is mounted on the actuator 18. The sensor head 84 only has the function of illuminating light and receiving reflected light, therefore the sensor head 84 itself is very compact.

[0164] In one embodiment, the sensor head 84 and focusing lens 85 may also be disposed within pressure chamber 57a (or pressure chamber 57b). In this case, the tip of the sensor head 84 is positioned toward the central portion 71a (or central portion 71b) of the diaphragm 55a (or diaphragm 55b), the sensor head 84 guides light toward the central portion 71a (or central portion 71b), and receives reflected light from the diaphragm 55a (or diaphragm 55b). A sensor target having light-reflecting properties may also be fixed to the central portion 71a (or central portion 71b). Furthermore, in one embodiment, the distance sensor 80 may also be a laser displacement meter.

[0165] In reference Figures 1 to 10In the described embodiment, the substrate holding device 10 includes two reference axes 13a, two movable axes 13b, two actuators 18, two movable stages 21, and two linear guides 26 arranged around a central axis CP. However, the number and spacing of these components are not limited to this embodiment. In one embodiment, the substrate holding device 10 may also include one movable axis 13b and two or more reference axes 13a arranged at appropriate intervals around the central axis CP. In this case, the substrate holding device 10 has one actuator 18, one movable stage 21, and one linear guide 26.

[0166] Furthermore, in one embodiment, the substrate holding device 10 may also include three or more movable axes 13b and three or more reference axes 13a arranged at appropriate intervals around the central axis CP. In this case, the substrate holding device 10 has three or more actuators 18, three or more movable stages 21, and three or more linear guides 26. Furthermore, in one embodiment, the motion control unit 40 may also be composed of multiple motion control units equipped with storage devices and computing devices. In one example, one of the multiple motion control units may be connected to motors 29a and 29b, and another may be connected to the distance sensor 80.

[0167] Figure 11 It is a schematic representation of having a reference. Figures 1 to 10 A top view of one embodiment of the substrate processing apparatus of the substrate holding device 10 described herein. Figure 12 yes Figure 11 The diagram shows a side view of the substrate holding apparatus 10. In this embodiment, the substrate processing apparatus 100 includes a substrate holding apparatus 10 and a processing head 200, which processes the first surface 1 of the wafer W held in the substrate holding apparatus 10 by contacting the processing tool 201 with the first surface 1 of the wafer W. The processing head 200 is disposed on the underside of the wafer W held by the substrate holding apparatus 10, and the position of the processing head 200 is fixed.

[0168] In this embodiment, the first surface 1 of the wafer W is the back surface of the wafer W where no device is formed or where no device is formed, i.e., the non-device surface. The second surface 2 of the wafer W, opposite to the first surface 1, is the surface where a device is formed or where a device is planned to be formed, i.e., the device surface. In this embodiment, the wafer W is held horizontally in the substrate holding device 10 with its first surface 1 facing down.

[0169] The specific operation of the substrate processing apparatus 100 in this embodiment is as follows. The substrate holding apparatus 10 contacts the periphery of the wafer W with multiple rollers 11a and 11b, causing the multiple rollers 11a and 11b to rotate around their respective axes and to perform circular motion, thereby causing the wafer W to rotate around its axis and to perform circular motion. The processing head 200 then contacts the processing tool 201 with the first surface 1 of the rotating and circularly moving wafer W, thereby processing the first surface 1 of the wafer W.

[0170] In this embodiment, the processing tool 201 is longer than the radius of the wafer W. One end of the processing tool 201 extends outward from the periphery of the wafer W, and the other end extends beyond the central axis CP of the substrate holding device 10. Therefore, the processing head 200 can make the processing tool 201 come into contact with the entire first surface 1 of the rotating wafer W. As a result, the processing tool 201 can process the entire first surface 1 of the outermost wafer W. The processing head 200 is positioned so as not to contact the rollers 11a and 11b, or the eccentric shafts 13a and 13b, when the wafer W is in circular motion.

[0171] According to this embodiment, the substrate holding device 10 can simultaneously perform circular motion and rotation of the wafer W around its axis with a simple structure. This combination of circular motion and rotation around the wafer W's axis increases the speed of each point on the surface of the wafer W. Therefore, the relative speed between the processing tool 201 and the surface of the wafer W increases, thereby increasing the processing speed of the wafer W.

[0172] In one embodiment, the processing tool 201 can also be a polishing tool for polishing the wafer W. Examples of polishing tools include polishing belts and grinding stones. Furthermore, in one embodiment, the processing tool 201 can also be a cleaning tool for cleaning the wafer W. An example of a cleaning tool is a cleaning belt. An example of a cleaning belt is a belt made of non-woven fabric.

[0173] The above embodiments are described with the aim of enabling those skilled in the art to carry out the present invention. Various modifications of the above embodiments can obviously be made by those skilled in the art, and the technical concept of the present invention can also be applied to other embodiments. Therefore, the present invention is not limited to the described embodiments, but is to be interpreted as encompassing the widest scope of the technical concept as defined by the claimed scope.

Claims

1. A substrate holding device, wherein the substrate is rotated about its axis while simultaneously performing a circular motion on the substrate, characterized in that, have: Multiple rollers capable of contacting the periphery of the substrate; Multiple electric motors that rotate the multiple rollers; Multiple eccentric shafts are arranged around a predetermined central axis; Multiple actuators, each having multiple pistons; as well as Multiple movable stages, each connected to one of the multiple pistons. The plurality of eccentric shafts have a plurality of first shaft portions and a plurality of second shaft portions, the plurality of second shaft portions being eccentrically located from the plurality of first shaft portions. The plurality of rollers are respectively fixed to the plurality of second shaft portions, and the plurality of first shaft portions are respectively connected to the plurality of motors. The plurality of eccentric shafts are composed of a plurality of movable shafts and a plurality of reference shafts. The plurality of movable stages have a plurality of bearings and a plurality of connecting components, the plurality of bearings supporting the plurality of movable shafts to enable rotation, and the plurality of connecting components being fixed to the plurality of pistons. The plurality of actuators are respectively connected to the plurality of movable stages and the plurality of movable shafts. The plurality of actuators are configured to move the plurality of movable axes and the plurality of movable stages together in a direction approaching the plurality of reference axes and in a direction away from the plurality of reference axes.

2. The substrate holding device according to claim 1, characterized in that, The plurality of eccentric shafts also have a plurality of intermediate shaft portions, which connect the plurality of first shaft portions to the plurality of second shaft portions. The plurality of first shaft portions are respectively fixed to the plurality of intermediate shaft portions, and the plurality of second shaft portions are respectively fixed to the plurality of intermediate shaft portions.

3. The substrate holding device according to claim 1, characterized in that, It also includes a motion control unit that causes the plurality of motors to rotate at the same speed and in the same phase.

4. The substrate holding device according to claim 1, characterized in that, The directions approaching the plurality of reference axes and the directions moving away from the plurality of reference axes are the directions toward the central axis and the directions moving away from the central axis.

5. The substrate holding device according to claim 1, characterized in that, The plurality of actuators each have: The piston; Housing, which is disposed away from the piston; and A diaphragm forms a pressure chamber between the piston and the housing.

6. The substrate holding device according to claim 5, characterized in that, The diaphragm membrane has the following characteristics: The central portion, which contacts the end of the piston; An inner wall portion, which is connected to the central portion and extends along the side of the piston; A folding section, which is connected to the inner wall portion and has a curved cross-section; and The outer wall portion is connected to the folded-back portion and is located outside the inner wall portion.

7. The substrate holding device according to claim 1, characterized in that, It also includes at least one non-contact distance sensor that measures the movement distance of at least one of the plurality of movable axes.

8. The substrate holding device according to claim 7, characterized in that, It also includes a motion control unit, which is configured to determine whether the substrate holding device is malfunctioning by comparing the measured value of the moving distance or an index value calculated based on multiple measured values ​​of the moving distance with a preset threshold.

9. The substrate holding device according to claim 8, characterized in that, The index value is the average position of at least one of the multiple movable shafts when the multiple rollers rotate more than one revolution.

10. The substrate holding device according to claim 8, characterized in that, The index value is the difference between the maximum and minimum values ​​of the position of at least one of the plurality of movable shafts during a period when the plurality of rollers rotate more than one revolution.

11. The substrate holding device according to claim 1, characterized in that, The plurality of actuators are configured to enable the plurality of movable shafts to move independently. The direction of movement of one of the plurality of movable axes is different from the direction of movement of another of the plurality of movable axes.

12. The substrate holding device according to claim 11, characterized in that, The directions of movement of one of the plurality of movable shafts and the directions of movement of another of the plurality of movable shafts are toward the central axis and away from the central axis, respectively.

13. A substrate holding device, wherein the substrate is rotated about its axis while simultaneously performing a circular motion on the substrate, characterized in that, have: Multiple rollers capable of contacting the periphery of the substrate; Multiple electric motors that rotate the multiple rollers; Multiple eccentric shafts are arranged around a predetermined central axis; An actuator having a piston; and A movable stage, which is connected to the piston. The plurality of eccentric shafts have a plurality of first shaft portions and a plurality of second shaft portions, the plurality of second shaft portions being eccentrically located from the plurality of first shaft portions. The plurality of rollers are respectively fixed to the plurality of second shaft portions, and the plurality of first shaft portions are respectively connected to the plurality of motors. The plurality of eccentric shafts are composed of movable shafts and a plurality of reference shafts. The movable stage has a bearing that supports the movable shaft for rotation, and a connecting component that is fixed to the piston. The actuator is connected to the movable shaft via the movable stage. The actuator is configured to move the movable shaft and the movable stage integrally in directions approaching and away from the plurality of reference axes. The actuator includes: piston; Housing, which is disposed away from the piston; and A diaphragm forms a pressure chamber between the piston and the housing.

14. The substrate holding device according to claim 13, characterized in that, The plurality of eccentric shafts also have a plurality of intermediate shaft portions, which connect the plurality of first shaft portions to the plurality of second shaft portions. The plurality of first shaft portions are respectively fixed to the plurality of intermediate shaft portions, and the plurality of second shaft portions are respectively fixed to the plurality of intermediate shaft portions.

15. The substrate holding device according to claim 13, characterized in that, It also includes a motion control unit that causes the plurality of motors to rotate at the same speed and in the same phase.

16. The substrate holding device according to claim 13, characterized in that, The directions approaching the plurality of reference axes and the directions moving away from the plurality of reference axes are the directions toward the central axis and the directions moving away from the central axis.

17. The substrate holding device according to claim 13, characterized in that, The diaphragm membrane has the following characteristics: The central portion, which contacts the end of the piston; An inner wall portion, which is connected to the central portion and extends along the side of the piston; A folding section, which is connected to the inner wall portion and has a curved cross-section; and The outer wall portion is connected to the folded-back portion and is located outside the inner wall portion.

18. The substrate holding device according to claim 13, characterized in that, It also features a non-contact distance sensor that measures the distance the movable shaft moves.

19. The substrate holding device according to claim 18, characterized in that, It also includes a motion control unit, which is configured to determine whether the substrate holding device is malfunctioning by comparing the measured value of the moving distance or an index value calculated based on multiple measured values ​​of the moving distance with a preset threshold.

20. The substrate holding device according to claim 19, characterized in that, The index value is the average position of the movable shaft when the plurality of rollers rotate more than one revolution.

21. The substrate holding device according to claim 19, characterized in that, The index value is the difference between the maximum and minimum values ​​of the position of the movable shaft during the period when the plurality of rollers rotate more than one revolution.

22. A substrate processing apparatus, characterized in that, have: The substrate holding device according to any one of claims 1 to 21; and A processing head that brings a processing tool into contact with a first surface of a substrate to process that first surface.

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