Conveyance robot

Abstract

This conveyance robot (100) includes robot arms (10, 20), hands (30, 40), a contact member which comes into contact with a workpiece (W) held by the hands (30, 40), a drive unit for moving the contact member, a detection unit for detecting a contact state of the contact member moved by the drive unit, and a control unit. The control unit determines, on the basis of the detection result of the contact state detected by the detection unit, a workpiece state including the position and / or the shape of the workpiece (W) held by the hands (30, 40), and / or a wear state of the hands (30, 40) and / or the contact member.

Description

Conveyance robot

[0001] The present disclosure relates to a conveyance robot.

[0002] Conventionally, conveyance robots that convey workpieces are known. For example, Japanese Patent No. 4262064 discloses a conveyance robot that conveys a substrate as a workpiece. The conveyance robot described in Japanese Patent No. 4262064 includes a hand that holds a workpiece. The hand is disposed on a linear movement mechanism installed on a turning base. The hand is also provided with a locking portion that locks an edge of the workpiece. Further, a workpiece holding portion that abuts against the edge of the workpiece is disposed separately from the locking portion on the turning base. In the conveyance robot described in Japanese Patent No. 4262064, by operating the linear movement mechanism to place the hand in a retracted position, the locking portion of the hand and the workpiece holding portion of the turning base sandwich and hold the workpiece on the hand. Then, this conveyance robot changes the orientation of the hand by rotating the turning base in a state where the locking portion and the workpiece holding portion sandwich and hold the workpiece on the hand.

[0003] Japanese Patent No. 4262064

[0004] Here, in the case of conveying a workpiece held by a hand like the conveyance robot described in Japanese Patent No. 4262064, abnormalities such as shape changes due to deformation of the workpiece, or wear of a member that abuts the workpiece when holding the workpiece may occur. In such a case, when the workpiece is fixed and held by sandwiching the workpiece disposed on the hand like the conveyance robot described in Japanese Patent No. 4262064, the position of the workpiece relative to the hand changes. When the position of the workpiece relative to the hand changes, it is conceivable that the accuracy of the position at which the workpiece is conveyed decreases during the conveyance operation of moving the hand to convey the workpiece. Therefore, it is desired to suppress a decrease in the accuracy of the workpiece position during the conveyance operation caused by a change in the position of the workpiece relative to the hand.

[0005] This disclosure is made to solve the above-mentioned problems, and one of its objectives is to provide a transport robot that can suppress the decrease in the accuracy of the workpiece position during transport operations caused by changes in the workpiece's position relative to the hand.

[0006] To achieve the above objective, a transport robot according to one aspect of this disclosure comprises a robot arm, a hand positioned at the tip of the robot arm and holding a workpiece, a contact member that contacts the workpiece held by the hand, a drive unit for moving the contact member, a detection unit for detecting the contact state of the contact member moved by the drive unit, and a control unit that determines, based on the detection result of the contact state detected by the detection unit, a workpiece state including at least one of the position and shape of the workpiece held by the hand, and at least one of the wear state of the hand and at least one of the contact member.

[0007] As described above, a transport robot according to one aspect of this disclosure includes a detection unit that detects the contact state of a contact member moved by a drive unit, and a control unit that determines, based on the detection result of the contact state detected by the detection unit, at least one of the workpiece state, including the position and shape of the workpiece held by the hand, and at least one of the wear state of the hand and at least one of the contact member. As a result, based on the detection result of detecting the contact state of the contact member, at least one of the workpiece state of the workpiece held by the hand and at least one of the wear state of the hand and at least one of the contact member is determined, so that measures can be taken to suppress a decrease in the accuracy of the transport operation, such as correcting the position of the workpiece during the transport operation or replacing the worn member, according to the determination result of determining at least one of the workpiece state and the wear state. As a result, it is possible to suppress a decrease in the accuracy of the workpiece position during the transport operation due to changes in the position of the workpiece relative to the hand.

[0008] According to this disclosure, as described above, it is possible to provide a transport robot that can suppress a decrease in the accuracy of the workpiece position during transport operations due to changes in the workpiece's position relative to the hand.

[0009] This is a schematic diagram showing the overall configuration of a substrate processing system equipped with a transport robot according to one embodiment of the present disclosure. This is a block diagram showing the configuration of a substrate processing system equipped with a transport robot. This is a schematic perspective view showing the transport robot. This is a top view for explaining the configuration of the hand. This is a side view for explaining the configuration of the hand. This is a schematic diagram for explaining the deviation of the center position of the workpiece. This is a diagram showing an example of time-series data representing the change in the detection result of the contact state. This is a flowchart diagram for explaining the control process of the workpiece transport method by the transport robot.

[0010] The embodiments of this disclosure will be described below with reference to the drawings.

[0011] The configuration of a transport robot 100 according to one embodiment of the present disclosure will be described with reference to Figures 1 to 7.

[0012] (Configuration of the Substrate Processing System) As shown in Figure 1, the transport robot 100 according to this embodiment transports the workpiece W in the substrate processing system 101. The substrate processing system 101 comprises the transport robot 100, a load lock unit 102, and a plurality of processing module units 103. In the example in Figure 1, the substrate processing system 101 comprises two load lock units 102 and four processing module units 103. The substrate processing system 101 also comprises a transport chamber 104 and an loading / unloading chamber 105. The substrate processing system 101 performs processing on workpiece W, such as semiconductor wafers and printed circuit boards. In this embodiment, the workpiece W is a disc-shaped substrate. The workpiece W is, for example, a glass substrate or a silicon substrate. Here, "disc-shaped" is described as a broad concept that also includes shapes deformed from a circle. A "disc-shaped" substrate includes a substrate provided with a notch or orientation flat that serves as a position reference. Furthermore, "disc-shaped" includes not only perfect circles but also ellipses.

[0013] Each of the multiple processing modules 103 performs a process on a workpiece W, such as coating a resist or etching it. The multiple processing modules 103 are arranged along the outer perimeter of the transport chamber 104. A load lock unit 102 is also located on the outer perimeter of the transport chamber 104. An loading / unloading chamber 105 is located on the opposite side of the load lock unit 102 from the transport chamber 104. On the opposite side of the loading / unloading chamber 105 from the load lock unit 102, there are three ports for attaching carriers 106, each capable of accommodating a workpiece W.

[0014] The transport robot 100 performs a transport operation that includes at least one of the following: unloading the workpiece W from the processing module 103 that processes the workpiece W, and loading the workpiece W into the processing module 103. In other words, the transport robot 100 is a substrate transport robot that loads and unloads the workpiece W, which is a substrate, between the load lock unit 102 and the processing module unit 103. The transport robot 100 is located in the center of the transport chamber 104. In the substrate processing system 101, for example, a robot located in the loading / unloading chamber 105 loads the workpiece W from the carrier 106 into the load lock unit 102. Then, the transport robot 100 of this embodiment transports the workpiece W from the load lock unit 102 to each of the multiple processing module units 103. For example, the transport robot 100 transports the workpiece W from the mounting unit 102a on which the workpiece W is placed in the load lock unit 102 to the mounting unit 103a on which the workpiece W is placed in the processing module unit 103. The workpieces W processed in each of the multiple processing module units 103 are transported from each of the multiple processing module units 103 to the load lock unit 102 by the transport robot 100. Then, the processed workpieces W are unloaded from the load lock unit 102 to the carrier 106 by a robot located in the loading / unloading room 105. Multiple workpieces W are stored in the carrier 106.

[0015] (Configuration of the transport robot) As shown in Figure 2, the transport robot 100 comprises a pair of robot arms 10 and 20, and a pair of hands 30 and 40. Hand 30 includes a blade member 31, a hand base portion 32, and a chuck portion 50. Hand 40 includes a blade member 41, a hand base portion 42, and a chuck portion 60. The chuck portion 50 has a contact member 51, a drive unit 52, and a position detection unit 53. The chuck portion 60 has a contact member 61, a drive unit 62, and a position detection unit 63. Hands 30 and 40 have a common structure to each other. That is, the blade member 31, hand base portion 32, and chuck portion 50 of hand 30 have a common structure to the blade member 41, hand base portion 42, and chuck portion 60 of hand 40, respectively. Furthermore, the contact member 51, drive unit 52, and position detection unit 53 of the chuck unit 50 have a common structure with the contact member 61, drive unit 62, and position detection unit 63 of the chuck unit 60, respectively. Note that the position detection unit 53 and position detection unit 63 are examples of detection units.

[0016] As shown in Figure 3, hands 30 and 40 are positioned at the respective ends of robot arms 10 and 20. Each of robot arms 10 and 20 rotates and extends / retracts by driving multiple joints. Furthermore, each of robot arms 10 and 20 operates independently by control processing by the control unit 81 shown in Figure 2. The transport robot 100 is a dual-arm type substrate transport robot that loads and unloads workpieces W, which are substrates, and is a horizontal multi-joint type substrate transport robot. Specifically, each of robot arms 10 and 20 has two interconnected link members that rotate in the horizontal plane. That is, each of robot arms 10 and 20 is a horizontal multi-joint robot arm having two link members that rotate relative to each other in the horizontal plane with the vertical Z direction as the axis of rotation. In this context, "horizontal" means parallel to the mounting surface on which the transport robot 100 is installed. If the transport robot 100 is positioned on an inclined surface or a wall, the robot arms 10 and 20 rotate in a plane parallel to the mounting surface, which is different from the horizontal plane relative to gravity.

[0017] A servo motor is provided as a drive source for each of the robot arms 10 and 20. In the transport robot 100, a separate servo motor is provided as a drive source for each joint of the robot arms 10 and 20. The servo motors as drive sources may be located inside the robot arms 10 and 20, or inside the base 100a. An encoder is provided for each servo motor provided at each joint to acquire the rotational speed of the servo motor. Furthermore, each of the robot arms 10 and 20 has a hand 30 and a hand 40 attached to the tip of two link members that are connected to each other, and the other end is connected to a common base 100a. Each of the robot arms 10 and 20 performs rotation and extension movements independently relative to the base 100a. The base 100a also has a lifting mechanism that moves each of the robot arms 10 and 20 independently in the vertical Z direction. This lifting mechanism, for example, has a servo motor as its drive source.

[0018] Each of the hands 30 and 40 holds a workpiece W. Specifically, one disc-shaped workpiece W is placed on each of the blade members 31 of hand 30 and 41 of hand 40. Each of the blade members 31 and 41 is a thin plate-shaped support plate that supports the workpiece W. Each of the blade members 31 and 41 has a U-shape with a bifurcated tip, and supports the back surface of the disc-shaped workpiece W from the Z2 direction, which is vertically downward. The base ends of each of the blade members 31 and 41 are connected to the hand base portion 32 and hand base portion 42, respectively. Each of the hand base portion 32 and hand base portion 42 is attached to the robot arm 10 and robot arm 20, respectively, and rotates along the horizontal plane relative to the robot arm 10 and robot arm 20. The workpieces W held by hands 30 and 40 are fixed to hands 30 and 40 by chucks 50 and 60, respectively. In other words, hands 30 and 40 are active-type substrate holding hands that hold the workpieces W in a fixed state, and are so-called edge-grip type substrate holding hands.

[0019] <Details of the hand> As shown in Figure 4, the chuck portion 50 is located on the hand 30. In the following description, since the structure is the same, only the description of the hand 30 and the chuck portion 50 will be given, and the description of the hand 40 and the chuck portion 60 will be omitted.

[0020] The contact member 51 is positioned on the hand 30 and moves in the X direction, which is the front-rear direction, within the hand 30 to contact the workpiece W held by the hand 30. Specifically, the contact member 51 is positioned from the inside to the outside of the hand base portion 32 and is a rod-shaped member that extends along the front-rear direction, which is the direction from the base end to the tip of the hand 30. The base end of the contact member 51 is positioned inside the hand base portion 32 of the hand 30 and extends in the X direction toward the tip along the Z1 direction surface of the blade member 31. The contact member 51 moves linearly along the linear guide 51a positioned inside the hand base portion 32. The contact member 51 also contacts the peripheral edge of the disc-shaped workpiece W at its tip.

[0021] The drive unit 52 moves the contact member 51. The drive unit 52 moves the contact member 51 along the X direction, which is the front-rear direction from the base end to the tip of the hand 30. The drive unit 52 has, for example, a servo motor 91 whose rotation is controlled by the control unit 81 as a drive source. The drive unit 52 also includes a linear motion mechanism 92 that converts the rotation of the servo motor 91 into linear motion. The linear motion mechanism 92 has, for example, a ball screw. In the ball screw of the linear motion mechanism 92, a screw shaft member 92a that rotates integrally with the output shaft of the servo motor 91 rotates around the X direction by the drive of the servo motor 91, causing a nut member 92b, which has a ball member arranged inside and meshes with the screw shaft member 92a, to move linearly in the X direction. The contact member 51 is connected to the nut member 92b in the ball screw of the linear motion mechanism 92, and moves linearly along the X direction together with the nut member 92b by the drive of the servo motor 91.

[0022] The position detection unit 53 detects the contact state of the contact member 51, which is moved by the drive unit 52. In this embodiment, the position detection unit 53 detects the position of the contact member 51 as the contact state of the contact member 51. The position detection unit 53 is located inside the hand base portion 32 of the hand 30 and detects the position of the contact member 51 in the front-rear direction on the hand 30. The position detection unit 53 includes, for example, an encoder 93 that detects the rotation of the servo motor 91 of the drive unit 52. By detecting the rotation of the servo motor 91 of the drive unit 52, the position detection unit 53 detects the position of the contact member 51 in the front-rear direction, which is the X direction. Similarly, in the hand 40, the drive unit 62 has a servo motor 91 and a linear movement mechanism 92, and the position detection unit 63 includes an encoder 93.

[0023] In this embodiment, the blade member 31 of the hand 30 has engaging portions 31a and 31b that engage with the workpiece W on which it is placed. Each of the engaging portions 31a and 31b is positioned at the tip of the bifurcated blade member 31. As shown in Figure 5, in the hand 30, the contact member 51 moves toward the tip of the hand 30 by the operation of the drive unit 52, and together with the engaging portions 31a and 31b of the blade member 31, it contacts the peripheral edge of the disc-shaped workpiece W. The contact member 51 and the engaging portions 31a and 31b contact the peripheral edge of the workpiece W, thereby holding the workpiece W placed on the blade member 31 by clamping it. The workpiece W is held in a fixed position relative to the hand 30 by being clamped between the contact member 51 and the engaging portions 31a and 31b in the XY plane.

[0024] Furthermore, as shown in Figure 2, the transport robot 100 is equipped with a temperature detection unit 71 and a temperature detection unit 72. The temperature detection unit 71 and the temperature detection unit 72 are located on the hand 30 and the hand 40, respectively. In this embodiment, the temperature detection unit 71 and the temperature detection unit 72 detect the temperature of the workpiece W held by the hand 30 and the hand 40, respectively. The temperature detection unit 71 and the temperature detection unit 72 output a signal indicating the detected temperature of the workpiece W to the control unit 81.

[0025] As shown in Figure 4, the temperature detection unit 71 and the temperature detection unit 72 are positioned at the tips of the contact member 51 and the contact member 61, respectively. The operation of the drive unit 52 and the drive unit 62 causes the contact member 51 and the contact member 61 to come into contact with the workpiece W, thereby detecting the temperature of the workpiece W while in contact with it. In other words, the temperature detection unit 71 and the temperature detection unit 72 are contact-type temperature sensors. Note that in Figure 4, only the temperature detection unit 71 positioned at the tip of the contact member 51 is shown, and the temperature detection unit 72 positioned on the contact member 61 is omitted from the illustration because its structure is the same.

[0026] As shown in Figure 2, the transport robot 100 also includes a control unit 81 and a storage unit 82. The control unit 81 is a computer having an arithmetic unit such as a CPU (Central Processing Unit). The storage unit 82 includes a storage device including flash memory such as an SSD (Solid State Drive). The control unit 81 may be positioned separately from the transport robot 100, or it may be positioned integrally with the transport robot 100. The control unit 81 is a robot controller that controls the operation of each part of the transport robot 100 based on programs and parameters stored in the storage unit 82.

[0027] The control unit 81 includes, for example, a main control unit that controls the operation of each joint of the robot arms 10 and 20 and the operation of the drive units 52 and 62; a servo control unit that controls the drive current output to the servo motors, which are drive sources, located in each joint of the robot arms 10 and 20 and in the drive units 52 and 62, based on commands from the main control unit; and a drive circuit unit that supplies power to each joint of the robot arms 10 and 20 and in the drive units 52 and 62. In the control unit 81, for example, the main control unit and the servo control unit each have a separate computing device such as a CPU. The control unit 81 controls the operation of each of the robot arms 10 and 20 and the operation of the drive units 52 and 62 by feedback control by controlling the operation of the servo motors, which are drive sources, based on the output from the encoder. In this embodiment, the control unit 81 controls the transport operation of a plurality of workpieces W. The control unit 81 controls the transport operation of the workpieces W based on a control signal from a higher-level control device that controls the entire substrate processing system 101. Furthermore, the control unit 81 moves the contact members 51 and 61 by controlling the operation of the drive units 52 and 62, and acquires the detection results of the contact state detected by the position detection units 53 and 63.

[0028] (Details of control by the control unit) The control unit 81 transports the workpiece W based on a preset amount of movement by controlling the movements of the robot arm 10 and hand 30 and the robot arm 20 and hand 40. The preset amount of movement is stored in the memory unit 82. Since the control of the transport operation using the robot arm 10 and hand 30 and the control of the transport operation using the robot arm 20 and hand 40 are similar, the following description will only explain the control of the transport operation using the robot arm 10 and hand 30, and will omit the explanation of the control of the transport operation using the robot arm 20 and hand 40.

[0029] For example, when transporting a workpiece W from the mounting section 102a of the load lock section 102 to the mounting section 103a of the processing module section 103, the control unit 81 controls the operation of the robot arm 10 and the hand 30 so that the workpiece W placed on the mounting section 102a is placed on the blade member 31 of the hand 30. With the workpiece W placed on the blade member 31, the control unit 81 controls the operation of the drive unit 52 to move the contact member 51 to a position where it contacts the workpiece W. As a result, the workpiece W is held in a fixed state on the hand 30 by the engaging sections 31a and 31b of the blade member 31 and the contact member 51. The control unit 81 detects, for example, that the contact member 51 has contacted the workpiece W based on a change in the current supplied to the drive unit 52. Then, with the workpiece W being held, the control unit 81 controls the operation of the robot arm 10 and the hand 30 based on a set amount of movement so that the workpiece W is transported to the mounting section 103a. Then, after transporting the workpiece W to the position of the mounting section 103a, the control unit 81 controls the operation of the drive unit 52 to move the contact member 51 to a position away from the workpiece W. By moving the contact member 51 to a position away from the workpiece W, the control unit 81 releases the fixing of the workpiece W in the hand 30 and places the workpiece W on the mounting section 103a.

[0030] In this embodiment, the control unit 81 determines, based on the detection result of the contact state detected by the position detection unit 53, the workpiece state, which includes at least one of the position and shape of the workpiece W held by the hand 30, and at least one of the wear state of the hand 30 and at least one of the contact member 51. The control unit 81 obtains the holding state of the workpiece W held by the hand 30 by the contact of the contact member 51 as the detection result of the contact state. Specifically, the control unit 81 obtains a detection result indicating the position of the contact member 51 that moves by the operation of the servo motor 91 of the drive unit 52 and is in contact with the disc-shaped workpiece W as the detection result of the contact state with respect to the disc-shaped workpiece W. Then, the control unit 81 determines the workpiece state and the wear state based on the obtained detection result.

[0031] <Correction of Movement Amount> As shown in Figure 6, if the shape of the workpiece W changes due to heat treatment or the like, the center position P of the workpiece W relative to the hand 30 changes. When the center position P changes, a shift occurs in the position where the workpiece W is transported during the transport operation. The example in Figure 6 shows an example of the shift in the center position P when the workpiece W is deformed from the size shown by the dotted line to the size shown by the solid line. When the size of the workpiece W changes, the position where the contact member 51 contacts the workpiece W relative to the hand 30 changes. Therefore, the center position P of the workpiece W relative to the hand 30 changes. In this embodiment, the control unit 81 transports the workpiece W while correcting the set movement amount by determining the position of the workpiece W relative to the hand 30 as the workpiece state based on the contact state detection result by the position detection unit 53. The control unit 81 determines the center position P of the workpiece W as the workpiece state based on the contact state detection result, and corrects the movement amount in the transport operation based on the center position P of the workpiece W relative to the hand 30. In other words, in this embodiment, the transport robot 100 does not use a detection unit such as a photoelectric sensor located at a distance from the transport robot 100, but instead uses a position detection unit 53 in the chuck unit 50 located on the hand 30 to detect the position of each workpiece W held by the hand 30.

[0032] Specifically, the control unit 81 obtains the position of the tip of the contact member 51 in contact with the peripheral edge of the workpiece W by acquiring the amount of movement of the contact member 51 by the drive unit 52 based on the detection result detected by the position detection unit 53. Then, the control unit 81 obtains the center position P of the workpiece W by calculating a circle passing through three points using the positions of the engaging portions 31a and 31b of the blade member 31 of the hand 30, which are set in advance and stored in the memory unit 82, and the acquired position of the tip of the contact member 51. The control unit 81 obtains the amount of displacement m1 of the workpiece W based on the difference between the center position P before correction, which is set in advance, and the center position P obtained based on the detection result of the position detection unit 53. As a result, the control unit 81 corrects the set amount of movement in the transport operation of the workpiece W to correct the acquired amount of displacement m1.

[0033] Furthermore, if the temperature of the workpiece W changes due to heat treatment or other reasons, the shape of the workpiece W may change according to the temperature of the workpiece W. Therefore, in this embodiment, the control unit 81 controls the transport operation of the workpiece W based on the temperature of the workpiece W detected by the temperature detection unit 71. For example, the control unit 81 obtains a predicted value of the amount of displacement of the workpiece W relative to the hand 30 based on the temperature of the workpiece W detected by the temperature detection unit 71, and corrects the amount of movement in the transport operation, which is set in advance, based on the obtained predicted value of the amount of displacement. The storage unit 82 stores in advance information that shows the change in shape of the workpiece W according to the temperature. The information that shows the change in shape of the workpiece W according to the temperature is, for example, table information that shows the relationship between the outer diameter of a disc-shaped workpiece W and the temperature. The control unit 81 obtains a predicted value of the outer diameter of the workpiece W held by the hand 30 based on the temperature of the workpiece W detected by the temperature detection unit 71 and the information stored in the storage unit 82. Then, the control unit 81 corrects the amount of movement in the transport operation of the workpiece W based on the detection result detected by the position detection unit 53 and the temperature of the workpiece W detected by the temperature detection unit 71. For example, the control unit 81 obtains a predicted value of the center position P of the workpiece W from the predicted value of the outer diameter of the workpiece W obtained by the temperature detection unit 71, and uses the average of the center position P of the workpiece W obtained from the detection result of the position detection unit 53 and the predicted value of the center position P of the workpiece W obtained from the temperature of the workpiece W detected by the temperature detection unit 71 to correct the amount of movement in the transport operation so that the workpiece W is transported to an appropriate position in the mounting unit 102a or mounting unit 103a.

[0034] Furthermore, during the transport operation of the workpiece W, the control unit 81 waits while holding the workpiece W, based on the temperature of the workpiece W detected by the temperature detection unit 71, so that the workpiece W reaches a temperature within a predetermined temperature range. The predetermined temperature range is stored in advance in the storage unit 82. For example, when transporting a heat-treated workpiece W, the control unit 81 waits to transport the workpiece W while holding it in the hand 30 until it cools to within the predetermined temperature range, in order to prevent the workpiece W from being transported at a temperature that is too high for the destination mounting unit 102a or mounting unit 103a. The control unit 81 transports the workpiece W to the destination mounting units 102a and 103a when the temperature of the workpiece W detected by the temperature detection unit 71 falls within the set predetermined temperature range.

[0035] Furthermore, the control unit 81 adjusts the position of the contact member 51 in accordance with the change in shape of the workpiece W due to temperature changes, based on the temperature of the workpiece W detected by the temperature detection unit 71, through the operation of the drive unit 52. Specifically, the control unit 81 obtains the outer diameter of the workpiece W as a shape based on the temperature of the workpiece W detected by the temperature detection unit 71 and table information stored in the storage unit 82 that represents the relationship between the outer diameter of the disc-shaped workpiece W and the temperature. Then, the control unit 81 adjusts the position of the contact member 51 in accordance with the change in shape of the workpiece W due to temperature changes by controlling the operation of the servo motor 91 of the drive unit 52 in accordance with the obtained outer diameter of the workpiece W as a shape. Here, when the temperature of the workpiece W rises, the workpiece W expands due to the heat, and the outer diameter of the workpiece W increases. On the other hand, when the temperature of the workpiece W decreases, the workpiece W that was expanded due to the heat contracts, and the outer diameter of the workpiece W decreases. If the temperature of the workpiece W detected by the temperature detection unit 71 is relatively high, the control unit 81 adjusts the position of the contact member 51 by moving it away from the engaging portions 31a and 31b at the tip of the blade member 31, towards the X2 direction, using the operation of the drive unit 52. If the temperature of the workpiece W detected by the temperature detection unit 71 is relatively low, the control unit 81 adjusts the position of the contact member 51 by moving it closer to the engaging portions 31a and 31b at the tip of the blade member 31, towards the X2 direction, using the operation of the drive unit 52. For example, if the temperature of the workpiece W detected by the temperature detection unit 71 decreases during the period when the control unit 81 is waiting while holding the workpiece W, it adjusts the position of the contact member 51 towards the engaging portions 31a and 31b at the tip of the blade member 31, towards the X1 direction, based on the table information stored in the storage unit 82, so as to follow the decrease in outer diameter due to the decrease in the temperature of the workpiece W. The control unit 81 adjusts the amount of pressure applied by the contact member 51 in accordance with the amount of change in the shape of the workpiece W due to temperature changes.

[0036] <Detection of workpiece abnormalities> The control unit 81 also detects abnormalities in the workpiece W by determining the shape of the workpiece W as the workpiece state based on the contact state detection result by the position detection unit 53. The control unit 81 obtains the outer diameter of the workpiece W by obtaining the position of the tip of the contact member 51 based on the detection result detected by the position detection unit 53. For example, the control unit 81 obtains the position of the tip of the contact member 51 in contact with the peripheral edge of the workpiece W by obtaining the amount of movement of the contact member 51 by the drive unit 52 based on the detection result detected by the position detection unit 53. The control unit 81 then obtains the outer diameter of the workpiece W by calculating a circle passing through three points using the positions of the engaging portions 31a and 31b on the blade member 31 of the hand 30, which are set in advance and stored in the storage unit 82, and the obtained position of the tip of the contact member 51. The control unit 81 then determines whether or not there are any shape abnormalities such as cracks or chips in the workpiece W based on the obtained outer diameter of the workpiece W.

[0037] For example, as shown in Figure 7, when the control unit 81 continuously and repeatedly transports multiple workpieces W of the same size, it stores time-series data in the storage unit 82 that represents the change in the contact state detection result by the position detection unit 53. For example, the outer diameter of the workpieces W acquired based on the detection result by the position detection unit 53 each time the transport is repeated is stored as time-series data representing the change in the contact state detection result. In Figure 7, an example of stored time-series data is shown, with the horizontal axis representing the detection timing and the vertical axis representing the acquired outer diameter of the workpieces W. For example, the control unit 81 determines a workpiece abnormality by comparing the time-series data of the outer diameter of the workpieces W acquired at the previous timing with the time-series data of the outer diameter of the workpieces W newly acquired, based on the stored time-series data. For example, when comparing the outer diameter of the workpieces W, which is time-series data acquired at timing T3 in Figure 7, with the outer diameter of the workpieces W, which is time-series data acquired at timing T4, the magnitude of the difference in the acquired outer diameters is V1. The control unit 81 determines that the time-series data acquired at timing T4 is abnormal if the difference V1 is greater than a preset threshold for workpiece abnormality determination, and determines that a workpiece abnormality has occurred in the workpiece W being transported at timing T4. The threshold for workpiece abnormality determination is preset and stored in the storage unit 82.

[0038] <Detection of wear> The control unit 81 also determines whether or not there is a wear abnormality in at least one of the hand 30 and the contact member 51 by determining the wear state based on the contact state detection result by the position detection unit 53. Specifically, the control unit 81 acquires time-series data representing the change in the detection result over a predetermined determination period D, and determines that there is a wear abnormality if the amount of change in the time-series data during the determination period D is greater than the determination threshold. The determination threshold is set in advance and stored in the storage unit 82.

[0039] For example, as shown in Figure 7, the control unit 81 acquires the outer diameter of the workpiece W for each repeated transport as time-series data representing the change in detection results over a predetermined judgment period D. The control unit 81 then determines wear abnormality by comparing the amount of change in the outer diameter of the workpiece W during the predetermined judgment period D with a preset judgment threshold. The predetermined judgment period D is, for example, the period from the time when the previously worn member was replaced to the present. The judgment period D is reset each time wear abnormality of the hand 30 and contact member 51 is determined. In the example in Figure 7, the hand 30 and contact member 51 are replaced between timing T1 and timing T2, and the judgment period D starts in the transport from timing T2 onward. The control unit 81 then acquires the amount of change in the outer diameter of the workpiece W during the judgment period D up to the present by acquiring the difference between the value of the outer diameter of the workpiece W at timing T2, which is when the judgment period D started, and the value of the outer diameter of the workpiece W acquired at the current timing. The control unit 81 determines that a wear abnormality has occurred at timing T5 if the amount of change obtained in this manner is greater than a preset judgment threshold, and that the hand 30 and the contact member 51, which are in contact with the workpiece W, are worn. For example, at timing T5, the control unit 81 obtains the difference V2 between the outer diameter of the workpiece W obtained at timing T2 and the outer diameter of the workpiece W obtained at timing T5 as the amount of change. The control unit 81 then compares the amount of change obtained as the difference V2 with the judgment threshold to determine whether or not a wear abnormality has occurred at timing T5.

[0040] (Control Processing for Workpiece Transport Method) Next, with reference to Figure 8, the control processing for the workpiece transport method by the transport robot 100 will be described. This control processing for the workpiece transport method is performed by the control unit 81. In the following description, the operations from step S1 to step S6 will be described as an example of controlling transport operations using the robot arm 10 and hand 30. The same applies to transport operations using the robot arm 20 and hand 40.

[0041] First, in step S1, the workpiece W is held in the hand 30. The control unit 81 controls the movement of the robot arm 10 and the hand 30 so that the workpiece W is placed on the blade member 31 of the hand 30, and operates the drive unit 52 to bring the contact member 51 into contact with the workpiece W held in the hand 30 so that the position of the workpiece W is fixed relative to the hand 30.

[0042] Next, in step S2, the contact state detection result is obtained. Based on the signal from the position detection unit 53, the control unit 81 obtains the position of the contact member 51 as the contact state detection result by obtaining the amount of movement of the contact member 51 by the drive unit 52 while the contact member 51 is in contact with the workpiece W.

[0043] Next, in step S3, it is determined whether or not a workpiece abnormality has been detected. If a workpiece abnormality is detected, the control process is terminated. If it is determined that there is no workpiece abnormality, the process proceeds to step S4. For example, the control unit 81 determines whether or not an abnormality has occurred in the workpiece W based on the detection result from the position detection unit 53, and if an abnormality has occurred in the workpiece W, it terminates the control process and stops the transport operation of the workpiece W. The control unit 81 then outputs information indicating that a workpiece abnormality has been detected to a higher-level control device in the substrate processing system 101 so as to notify it that an abnormality has been detected in the workpiece W. The substrate processing system 101 notifies the information indicating that an abnormality has been detected in the workpiece W using a display device or a notification device such as a speaker located in the substrate processing system 101.

[0044] In step S4, it is determined whether or not an abnormality in wear has been determined. If it is determined that there is an abnormality in wear, the control processing is ended. If it is determined that there is no abnormality in wear, the process proceeds to step S5. The control unit 81 determines whether or not there is an abnormality in wear based on the detection result from the position detection unit 53, and when it is determined that there is an abnormality in wear, ends the control processing and stops the transfer operation of the workpiece W. Then, the control unit 81 outputs information indicating that an abnormality in wear has been determined to a host control device in the substrate processing system 101 so as to prompt replacement of the hand 30 and the contact member 51. The substrate processing system 101 notifies information indicating that an abnormality in wear has been detected via a notification device such as a display device or a speaker disposed in the substrate processing system 101.

[0045] In step S5, the movement amount in a preset transfer operation is corrected based on the detection result of the contact state by the position detection unit 53. Specifically, the center position P of the workpiece W relative to the hand 30 is acquired from the obtained detection result, and the set movement amount is corrected in accordance with the acquired center position P.

[0046] Next, in step S6, the workpiece W is transferred. The control unit 81 executes the transfer operation of the workpiece W held by the hand 30 by controlling the operations of the robot arm 10 and the hand 30 based on the movement amount corrected in step S5.

[0047] (Effects of the Embodiment) In the present embodiment, the following effects can be obtained.

[0048] In the present embodiment, as described above, the transfer robot 100 includes position detection units 53 and 63 serving as detection units that detect the contact state of contact members 51 and 61 moved by drive units 52 and 62, respectively. The transfer robot 100 also includes a control unit 81 that: determines at least one of a workpiece state including at least one of the position and shape of a workpiece W held by a hand 30, and a wear state of at least one of the hand 30 and the contact member 51 based on the detection result of the contact state detected by the position detection unit 53; and determines at least one of a workpiece state including at least one of the position and shape of a workpiece W held by a hand 40, and a wear state of at least one of the hand 40 and the contact member 61 based on the detection result of the contact state detected by the position detection unit 63. Accordingly, based on the detection results obtained by detecting the contact state of the contact members 51 and 61, at least one of the workpiece state of the workpiece W held by the hand 30 and the wear state of at least one of the hand 30 and the contact member 51 is determined, and at least one of the workpiece state of the workpiece W held by the hand 40 and the wear state of the transfer robot 100 including at least one of the hand 40 and the contact member 61 is determined. Therefore, according to the determination result obtained by determining at least one of the workpiece state and the wear state, measures can be taken to suppress a decrease in accuracy of the transfer operation, such as correcting the transfer position in the transfer operation of the workpiece W, or replacing a worn member. As a result, a decrease in the positional accuracy of the workpiece W during the transfer operation caused by a change in the position of the workpiece W relative to the hands 30 and 40 can be suppressed.

[0049] Furthermore, the transport robot 100 includes position detection units 53 and 63 that detect the positions of the contact members 51 and 61 as the contact state of the contact members 51 and 61. The control unit 81 determines at least one of the workpiece state and the wear state based on the detection results indicating the positions of the contact members 51 and 61 that are in contact with the workpiece W due to the operation of the drive units 52 and 62. As a result, by detecting the positions of the contact members 51 and 61 that are in contact with the workpiece W using the position detection units 53 and 63, the positional relationship of the workpiece W with respect to the hands 30 and 40 can be easily and accurately detected. Therefore, since at least one of the workpiece state and the wear state can be easily and accurately detected based on the detection results indicating the positions of the contact members 51 and 61, the decrease in the accuracy of the workpiece W's position during transport can be easily and more effectively suppressed.

[0050] The contact members 51 and 61 are positioned on the hands 30 and 40 and move in the front-rear direction within the hands 30 and 40 to contact the workpiece W held by the hands 30 and 40. The position detection units 53 and 63 are positioned on the hands 30 and 40 and detect the front-rear position of the contact members 51 and 61 within the hands 30 and 40. This allows the workpiece W held by the hands 30 and 40 to be easily fixed in the hands 30 and 40 by moving the contact members 51 and 61 in the front-rear direction, and also allows the position of the contact members 51 and 61 to be easily detected by detecting their front-rear position. Therefore, displacement of the workpiece W during transport can be easily suppressed, and at least one of the workpiece condition and wear condition can be easily detected. As a result, a decrease in the accuracy of the workpiece W's position during transport due to changes in the workpiece W's position relative to the hands 30 and 40 can be more easily suppressed.

[0051] The workpiece W includes a disc-shaped substrate or a jig that mimics a disc-shaped substrate. The hand 30 includes a blade member 31 on which the disc-shaped workpiece W is placed. The blade member 31 has engaging portions 31a and 31b that engage with the placed workpiece W. The contact member 51 contacts the peripheral edge of the disc-shaped workpiece W together with the engaging portions 31a and 31b of the blade member 31 by the operation of the drive unit 52. The control unit 81 determines, based on the detection result of the contact state with the disc-shaped workpiece W, the workpiece state including at least one of the position and shape of the disc-shaped workpiece W, and at least one of the wear state of the engaging portions 31a, 31b, and at least one of the contact member 51. This makes it possible to suppress a decrease in the accuracy of the position of the workpiece W during transport operation due to changes in the position of the workpiece W relative to the hands 30 and 40, even when transporting a disc-shaped workpiece W including a disc-shaped substrate or a jig that mimics a disc-shaped substrate. For example, when transporting a disc-shaped substrate as the workpiece W, the substrate may deform during the processing steps. Therefore, when transporting a disc-shaped substrate as the workpiece W, by determining the workpiece state, which includes at least one of the position and shape of the disc-shaped workpiece W, it is possible to effectively suppress a decrease in the accuracy of the workpiece W's position during transport due to changes in the workpiece W's position relative to the hands 30 and 40.

[0052] The control unit 81 transports the workpiece W based on the set amount of movement, and transports the workpiece W while correcting the set amount of movement by determining the position of the workpiece W relative to the hands 30 and 40 as the workpiece state based on the detection result of the contact state. As a result, even if the shape of the workpiece W changes due to deformation of the workpiece W, the set amount of movement can be corrected based on the detection result of the contact state of the contact members 51 and 61, thereby effectively suppressing a decrease in the accuracy of the position of the workpiece W in the transport operation due to changes in the position of the workpiece W relative to the hands 30 and 40.

[0053] The control unit 81 acquires time-series data representing the change in the detection result over a predetermined judgment period D, and determines that there is a wear abnormality if the amount of change in the time-series data during the judgment period D is greater than the judgment threshold. Here, if the transport operation is performed while the wear of the parts that contact the workpiece W, such as the hands 30 and 40 or the contact members 51 and 61, is high, it is conceivable that the hands 30 and 40 will not adequately hold the workpiece W, or that positional misalignment will occur during the transport operation. Taking this into consideration, as in this embodiment, the control unit 81 determines that there is a wear abnormality if the amount of change in the time-series data representing the change in the detection result during the judgment period D is greater than the judgment threshold, thereby preventing the transport operation from being performed while the parts that contact the workpiece W are high.

[0054] The transport robot 100 includes temperature detection units 71 and 72 that detect the temperature of the workpiece W held by the hands 30 and 40. The control unit 81 controls the transport operation of the workpiece W based on the temperature of the workpiece W detected by the temperature detection units 71 and 72. This allows the position during the transport operation to be corrected according to the deformation of the workpiece W if the workpiece W deforms in accordance with the temperature. Therefore, even when the workpiece W deforms in accordance with the temperature, it is possible to suppress a decrease in the accuracy of the position of the workpiece W during the transport operation due to changes in the position of the workpiece W relative to the hands 30 and 40. In addition, since the temperature of the workpiece W can be monitored by the temperature detection units 71 and 72, when transporting a heated workpiece W, the transport of the workpiece W can be delayed until it cools to an appropriate temperature while still being held in the hands 30 and 40. Therefore, it is possible to suppress the transport of high-temperature workpieces W, and thus easily reduce the heat burden on the equipment at the transport destination.

[0055] The control unit 81 adjusts the positions of the contact members 51 and 61 in accordance with the change in shape of the workpiece W due to temperature changes, based on the temperature of the workpiece W detected by the temperature detection units 71 and 72, through the operation of the drive units 52 and 62. This allows the positions of the contact members 51 and 61 to be adjusted in response to changes in the shape of the workpiece W, even when the shape of the workpiece W changes due to temperature changes. As a result, the magnitude of the force applied to the workpiece W by the contact members 51 and 61 can be easily set to an appropriate magnitude. Consequently, it is possible to suppress the occurrence of abnormalities such as deformation or chipping in the workpiece W due to excessive force applied to the workpiece W by the contact members 51 and 61. Furthermore, it is possible to suppress the insufficient holding of the workpiece W by the hands 30 and 40 due to excessive force applied to the workpiece W by the contact members 51 and 61.

[0056] The transport robot 100 includes a pair of hands 30 and 40. Contact members 51 and 61 contact the held workpiece W in at least one of the pair of hands 30 and 40. This makes it possible to suppress a decrease in the accuracy of the workpiece W's position during transport operation due to changes in the workpiece W's position relative to the hands 30 and 40, even when transporting the workpiece W using the pair of hands 30 and 40. Therefore, by using the pair of hands 30 and 40, the efficiency of transporting the workpiece W can be improved, and a decrease in the accuracy of the transport operation due to changes in the workpiece W's position relative to the hands 30 and 40 can be effectively suppressed.

[0057] The transport robot 100 includes horizontally articulated robot arms 10 and 20. This allows the horizontally articulated robot arms 10 and 20 to suppress a decrease in the accuracy of the workpiece position caused by changes in the workpiece position relative to the hands 30 and 40 during horizontal transport operations.

[0058] The transport robot 100 includes a pair of robot arms 10 and 20. Contact members 51 and 61 contact the held workpiece W in hands 30 and 40 located at the end of at least one of the pair of robot arms 10 and 20. This suppresses a decrease in the accuracy of the workpiece W's position during transport due to changes in the workpiece W's position relative to the hands 30 and 40, even when transporting the workpiece W using the pair of robot arms 10 and 20. Therefore, using a pair of robot arms 10 and 20 improves the efficiency of transporting the workpiece W and effectively suppresses a decrease in the accuracy of the transport operation due to changes in the workpiece W's position relative to the hands 30 and 40.

[0059] Each of the drive units 52 and 62 includes a servo motor 91. The control unit 81 determines at least one of the workpiece state and the wear state based on the detection result of the contact state of the contact members 51 and 61 that move due to the operation of the servo motor 91. As a result, since the drive units 52 and 62 that move the contact members 51 and 61 include a servo motor 91 whose rotation is controlled by the control unit 81, the movement of the contact members 51 and 61 can be easily controlled by controlling the operation of the servo motor 91 by the control unit 81.

[0060] The transport robot 100 includes position detection units 53 and 63 that detect the positions of the contact members 51 and 61 as the contact state of the contact members 51 and 61. The position detection units 53 and 63 include encoders 93 that detect the rotation of the servo motor 91, and by detecting the rotation of the servo motor 91, the positions of the contact members 51 and 61 are detected. As a result, since the position detection units 53 and 63 include encoders 93 that detect the rotation of the servo motor 91, the operation of the servo motor 91 can be easily and accurately controlled by feedback control using the detection results of the encoders 93. Furthermore, since the positions of the contact members 51 and 61 can be detected by the detection results of the encoders 93 used to control the operation of the servo motor 91, the complexity of the transport robot 100's device configuration can be suppressed compared to a case where the configuration for detecting the positions of the contact members 51 and 61 is arranged separately from the encoders 93.

[0061] The drive units 52 and 62 include a linear motion mechanism 92 that converts the rotation of the servo motor 91 into linear motion. The linear motion mechanism 92 has a ball screw. As a result, the linear motion mechanism 92 with the ball screw can convert the rotation of the servo motor 91 into linear motion, so that the contact members 51 and 61 can be easily moved linearly by the operation of the servo motor 91. Therefore, the contact members 51 and 61 can be easily moved linearly along the direction toward the workpiece W held by the hands 30 and 40, so that the workpiece W can be easily fixed in the hands 30 and 40.

[0062] [Variations] The embodiments disclosed herein should be considered in all respects to be illustrative and not restrictive. The scope of this disclosure is indicated by the claims rather than the description of the embodiments above, and further includes all modifications (variations) in the meaning and scope equivalent to the claims.

[0063] For example, in the above embodiment, the encoders 93 of the position detection units 53 and 63, which act as detection units, detect the rotation of the servo motors 91 of the drive units 52 and 62 to detect the positions of the contact members 51 and 61 as the contact state of the contact members 51 and 61. However, the present disclosure is not limited thereto. In this disclosure, the position detection unit may be configured to directly detect the position of the contact member in the front-rear direction to obtain a detection result indicating the position of the contact member as the contact state. The position detection unit may be contact-type or non-contact-type. For example, the position detection unit may be a magnetic linear scale, an optical linear scale, or a potentiometer. Alternatively, the detection unit for detecting the contact state of the contact member may be configured to detect the magnitude of the force applied to the contact member when it is in contact with the workpiece as the contact state. In that case, the control unit obtains a detection result indicating the magnitude of the force applied to the contact member in contact with the workpiece as the detection result of the contact state, and determines at least one of the workpiece state and the wear state based on the detection result indicating the magnitude of the force applied to the contact member.

[0064] Furthermore, although the above embodiment shows an example in which the contact members 51 and 61 are moved by drive units 52 and 62 including a servo motor 91, the disclosure is not limited thereto. In this disclosure, the drive unit that moves the contact members may include an air actuator. The drive unit may also include a solenoid coil. The drive unit may also include a linear motor. In addition, if the drive unit includes a rotary motor, it may also include a linear movement mechanism other than a ball screw, such as a belt and pulley or rack and pinion.

[0065] Furthermore, in the above embodiments, the contact members 51 and 52 were shown as members that move along the front-rear direction from the base end to the tip in the hands 30 and 40, but the present disclosure is not limited thereto. In the present disclosure, the contact members may be moved in directions other than the front-rear direction to make contact with the workpiece. Also, multiple contact members may be arranged in a single hand. In that case, the position of each of the multiple contact members may be detected, and the positions of each of the detected multiple contact members may be combined to detect at least one of the workpiece state and the wear state. Also, if multiple contact members that are moved by a drive unit are arranged, the workpiece may be clamped and fixed by the multiple contact members alone. In other words, the blade member of the hand does not need to have an engaging portion.

[0066] Furthermore, although the above embodiment shows an example where the workpiece W is a disc-shaped substrate, the present disclosure is not limited to this. In this disclosure, the workpiece W may be a jig that mimics a disc-shaped substrate. Alternatively, the workpiece W may be a plate-shaped member having a shape other than a disc, such as a rectangle. Moreover, the workpiece W does not have to be plate-shaped.

[0067] Furthermore, although the above embodiment shows an example in which bifurcated plate-shaped blade members 31 and 41 are arranged on the hands 30 and 40, the present disclosure is not limited thereto. In the present disclosure, the blade members of the hand do not have to be bifurcated. The blade members may be rectangular plate-shaped. Also, the blade members may be branched into three or more parts. Also, multiple blade members may be arranged on a single hand. In that case, contact members may be arranged on all of the multiple blade members, or contact members may be arranged on only some of them. Also, when contact members are arranged on multiple blade members, the contact state of the contact members may be detected on only some of the multiple blade members, and at least one of the workpiece state and the wear state may be determined based on the detection result of the contact state.

[0068] Furthermore, in the above embodiment, an example was shown in which the control unit 81 performs the following actions based on the detection result of the contact state: determining the center position P of the workpiece W as the workpiece state, determining the outer diameter of the workpiece as the workpiece state, and determining the wear state of the hand 30 and contact member 51 or the hand 40 and contact member 61. However, the present disclosure is not limited thereto. In this disclosure, at least one of the workpiece state, including at least one of the workpiece position and shape, and the wear state of at least one of the hand and contact member, may be determined. For example, the workpiece state, including the workpiece position and shape, may not be determined, and only the wear state of the members may be determined. In addition, at least one of the following may be performed: correction of the amount of movement in the workpiece transport operation, detection of workpiece abnormalities, and determination of the wear state.

[0069] Furthermore, while the above embodiment shows an example of determining a workpiece abnormality by comparing time-series data acquired at the previous timing with newly acquired time-series data based on stored time-series data, this disclosure is not limited to this. In this disclosure, a workpiece abnormality may be determined based on a single detection result by the detection unit without acquiring time-series data. For example, the outer diameter of the workpiece may be acquired based on the detection result, and the workpiece abnormality may be determined by comparing the acquired outer diameter with a preset threshold value for the outer diameter.

[0070] Furthermore, in the above embodiment, an example was shown in which wear abnormality is determined when the amount of change in time-series data during the determination period D is greater than a predetermined determination threshold, by resetting the determination period D each time a worn member is replaced. However, the present disclosure is not limited to this. In this disclosure, the determination period may be reset even if the member is not replaced. For example, the determination period may be reset at predetermined intervals, or it may be reset each time maintenance is performed.

[0071] Furthermore, in the above embodiment, an example was shown in which the center position P of the workpiece W is obtained from a predicted value of the outer diameter of the workpiece W by obtaining the center position P of the workpiece W based on the detection result of the contact state of the contact members 51 and 61, and by detecting the temperature of the workpiece W with temperature detection units 71 and 72 arranged on the contact members 51 and 61. However, the disclosure is not limited to this. In this disclosure, the position of the workpiece may be determined as the workpiece state based only on the detection result of the contact state of the contact members 51 and 61, without arranging a temperature detection unit. Also, when a temperature detection unit is arranged, the temperature detection unit may be arranged at a position other than the contact members on the hand. Also, the temperature detection unit may be arranged at a position other than the hand. The temperature detection unit may be contact type or non-contact type. Also, when a temperature detection unit is arranged, the position of the contact members may not be adjusted based on the temperature of the workpiece. Also, without arranging a temperature detection unit, the position of the contact members may be adjusted in accordance with the change in the shape of the workpiece caused by temperature changes. For example, by arranging a sensor that detects the shape of the workpiece, the position of the contact members may be adjusted according to the detected shape of the workpiece. The sensor used to detect the shape of the workpiece may be, for example, a photoelectric sensor, a laser sensor, an ultrasonic sensor, a magnetic sensor, a capacitive sensor, or a contact-type mechanical sensor.

[0072] Furthermore, in the above embodiment, an example was shown in which the center position P of the workpiece W is obtained using the position of the tip of the contact member 51 and the positions of the engaging portions 31a and 31b, by obtaining the position of the contact member 51 based on the detection result indicating the positions of the contact members 51 and 61 detected by the position detection units 53 and 63 as detection units as the result of detecting the contact state, but the present disclosure is not limited thereto. In this disclosure, the center position of the disc-shaped workpiece relative to the hand may be obtained using the detection result indicating the position of the contact member and the outer diameter of the workpiece predicted based on the temperature of the workpiece detected by the temperature detection unit.

[0073] Furthermore, although the above embodiment shows an example in which the transport robot 100 is a dual-arm robot equipped with a pair of robot arms 10 and 20, the present disclosure is not limited thereto. In this disclosure, the transport robot may be equipped with only one robot arm, or it may be equipped with three or more robot arms. Also, when a pair of robot arms are provided, a contact member that contacts the workpiece may be provided in the hand located at the tip of one of the robot arms of the pair. Also, when contact members are provided on both of the robot arms of the pair, the contact state of only one of the contact members may be detected, and at least one of the workpiece state and the wear state may be determined based on the detection result. For example, when one of the pair of robot arms performs a loading operation and the other robot arm performs an unloading operation, by detecting the contact state of the contact member on either one of the pair of robot arms to determine at least one of the workpiece state and the wear state, it is possible to suppress a decrease in the accuracy of the workpiece position in the transport operation due to changes in the position of the workpiece relative to the hand, while suppressing an increase in the processing load of the control processing and a complexity of the device configuration. Similarly, when there are three or more robot arms, contact members that contact the workpiece may be provided in the hands positioned at the ends of some of the robot arms. Alternatively, multiple hands may be provided for a single robot arm.

[0074] Furthermore, while the above embodiments show examples in which servo motors, which serve as drive sources and are located at each of the multiple joints of the robot arms 10 and 20, are controlled independently of each other, the disclosure is not limited to this. In this disclosure, some of the multiple joints of the robot arm may be controlled in conjunction with each other.

[0075] Furthermore, while the above embodiment shows an example in which a pair of robot arms 10 and 20 have a common structure, and a pair of hands 30 and 40 have a common structure, the disclosure is not limited to this. In this disclosure, a pair of robot arms may have different structures. Also, a pair of hands may have different structures.

[0076] Furthermore, while the above embodiment shows an example in which the transport robot 100 transports the workpiece W between the load lock unit 102 and the processing module unit 103 in the substrate processing system 101, the disclosure is not limited to this. In this disclosure, the transport robot may transport the workpiece between the load lock unit and the carrier in the loading / unloading chamber of the substrate processing system. Alternatively, the transport robot may transport the workpiece in a system different from the substrate processing system of the above embodiment. For example, the workpiece may be transported directly from the carrier in which it is stored to the processing module.

[0077] Furthermore, in the above embodiment, an example was shown in which the control unit 81 that controls the operation of the robot arms 10 and 20 also controls the determination of the workpiece state and the determination of the wear state, but the present disclosure is not limited thereto. In this disclosure, a control unit that controls the determination of the workpiece state or the determination of the wear state may be provided separately from the robot control unit that controls the operation of the robot arms.

[0078] The functions of the elements disclosed herein can be performed using circuits or processing circuits, including general-purpose processors, dedicated processors, integrated circuits, ASICs (Application Specific Integrated Circuits), conventional circuits, and / or combinations thereof, configured or programmed to perform the disclosed functions. A processor is considered a processing circuit or circuit because it includes transistors and other circuits. In this disclosure, a circuit, unit, or means is hardware that performs the enumerated functions, or hardware programmed to perform the enumerated functions. The hardware may be hardware disclosed herein, or other known hardware that is programmed or configured to perform the enumerated functions. If the hardware is a processor, which is considered a type of circuit, then the circuit, means, or unit is a combination of hardware and software, and the software is used to configure the hardware and / or the processor.

[0079] [Embodiments] The exemplary embodiments described above will be understood by those skilled in the art to be specific examples of the following embodiments.

[0080] (Aspect 1) A transport robot comprising: a robot arm; a hand positioned at the tip of the robot arm and holding a workpiece; a contact member that contacts the workpiece held by the hand; a drive unit for moving the contact member; a detection unit for detecting the contact state of the contact member moved by the drive unit; and a control unit that determines, based on the detection result of the contact state detected by the detection unit, a workpiece state including at least one of the position and shape of the workpiece held by the hand, and at least one of the wear state of the hand and at least one of the contact member.

[0081] (Aspect 2) The transport robot according to aspect 1, wherein the detection unit includes a position detection unit that detects the position of the contact member as the contact state of the contact member, and the control unit determines at least one of the workpiece state and the wear state based on the detection result which indicates the position of the contact member that is in contact with the workpiece by the operation of the drive unit.

[0082] (Aspect 3) The transport robot according to aspect 2, wherein the contact member is positioned on the hand and moves in the front-rear direction on the hand to contact the workpiece held by the hand, and the position detection unit is positioned on the hand and detects the position of the contact member in the front-rear direction on the hand.

[0083] (Aspect 4) The transport robot according to any one of aspects 1 to 3, wherein the workpiece includes a disc-shaped substrate or a jig that mimics the disc-shaped substrate, the hand includes a blade member on which the disc-shaped workpiece is placed, the blade member has an engaging portion that engages with the placed workpiece, the contact member contacts the peripheral edge of the disc-shaped workpiece together with the engaging portion of the blade member by the operation of the drive unit, and the control unit determines, based on the detection result of the contact state with the disc-shaped workpiece, the workpiece state including at least one of the position and shape of the disc-shaped workpiece and at least one of the wear state of the engaging portion and the contact member.

[0084] (Aspect 5) The transport robot according to any one of aspects 1 to 4, wherein the control unit transports the workpiece based on a set amount of movement, and transports the workpiece while correcting the set amount of movement by determining the position of the workpiece relative to the hand as the workpiece state based on the detection result of the contact state.

[0085] (Aspect 6) The transport robot according to any one of aspects 1 to 5, wherein the control unit acquires time-series data representing the change in the detection result over a predetermined determination period, and determines that there is a wear abnormality when the amount of change in the time-series data during the determination period is greater than a determination threshold.

[0086] (Aspect 7) A transport robot according to any one of aspects 1 to 6, further comprising a temperature detection unit for detecting the temperature of the workpiece held in the hand, wherein the control unit controls the transport operation of the workpiece based on the temperature of the workpiece detected by the temperature detection unit.

[0087] (Aspect 8) The transport robot according to aspect 7, wherein the control unit adjusts the position of the contact member in accordance with the change in the shape of the workpiece due to the temperature change, based on the temperature of the workpiece detected by the temperature detection unit, by the operation of the drive unit.

[0088] (Aspect 9) The transport robot according to any one of aspects 1 to 8, wherein the hand includes a pair of hands, and the contact member contacts the held workpiece in at least one of the pair of hands.

[0089] (Aspect 10) The transport robot according to any one of aspects 1 to 9, wherein the robot arm includes a horizontally articulated robot arm.

[0090] (Aspect 11) The transport robot according to any one of aspects 1 to 10, wherein the robot arm includes a pair of robot arms, and the contact member contacts the workpiece held by the hand, which is positioned at the tip of at least one of the pair of robot arms.

[0091] (Aspect 12) The transport robot according to any one of aspects 1 to 11, wherein the drive unit includes a servo motor, and the control unit determines at least one of the workpiece state and the wear state based on the detection result of the contact state of the contact member that moves by the operation of the servo motor.

[0092] (Aspect 13) The transport robot according to aspect 12, wherein the detection unit includes a position detection unit that detects the position of the contact member as the contact state of the contact member, and the position detection unit includes an encoder that detects the rotation of the servo motor, and the position of the contact member is detected by detecting the rotation of the servo motor.

[0093] (Aspect 14) The transport robot according to aspect 12 or aspect 13, wherein the drive unit includes a linear motion mechanism that converts the rotation of the servo motor into linear motion, and the linear motion mechanism has a ball screw.

[0094] 10, 20 Robot arm 30, 40 Hand 31, 41 Blade member 31a, 31b Engaging part 51, 61 Contact member 52, 62 Drive unit 53, 63 Position detection unit (detection unit) 71, 72 Temperature detection unit 81 Control unit 91 Servo motor 92 Linear movement mechanism 93 Encoder 100 Transport robot

Claims

1. A transport robot comprising: a robot arm; a hand positioned at the tip of the robot arm for holding a workpiece; a contact member that contacts the workpiece held by the hand; a drive unit for moving the contact member; a detection unit for detecting the contact state of the contact member moved by the drive unit; and a control unit that determines, based on the detection result of the contact state detected by the detection unit, a workpiece state including at least one of the position and shape of the workpiece held by the hand, and at least one of the wear state of the hand and at least one of the contact member.

2. The transport robot according to claim 1, wherein the detection unit includes a position detection unit that detects the position of the contact member as the contact state of the contact member, and the control unit determines at least one of the workpiece state and the wear state based on the detection result which indicates the position of the contact member that is in contact with the workpiece by the operation of the drive unit.

3. The transport robot according to claim 2, wherein the contact member is positioned on the hand and moves in the front-rear direction within the hand to contact the workpiece held by the hand, and the position detection unit is positioned on the hand and detects the position of the contact member in the front-rear direction within the hand.

4. The transport robot according to claim 1, wherein the workpiece includes a disc-shaped substrate or a jig that mimics the disc-shaped substrate, the hand includes a blade member on which the disc-shaped workpiece is placed, the blade member has an engaging portion that engages with the placed workpiece, the contact member contacts the peripheral edge of the disc-shaped workpiece together with the engaging portion of the blade member by the operation of the drive unit, and the control unit determines, based on the detection result of the contact state with the disc-shaped workpiece, the workpiece state including at least one of the position and shape of the disc-shaped workpiece and at least one of the wear state of the engaging portion and the contact member.

5. The transport robot according to claim 1, wherein the control unit transports the workpiece based on a set amount of movement, and transports the workpiece while correcting the set amount of movement by determining the position of the workpiece relative to the hand as the workpiece state based on the detection result of the contact state.

6. The transport robot according to claim 1, wherein the control unit acquires time-series data representing the change in the detection result over a predetermined determination period, and determines that there is a wear abnormality if the amount of change in the time-series data during the determination period is greater than a determination threshold.

7. The transfer robot according to claim 1, further comprising a temperature detection unit for detecting the temperature of the workpiece held in the hand, wherein the control unit controls the transfer operation of the workpiece based on the temperature of the workpiece detected by the temperature detection unit.

8. The transport robot according to claim 7, wherein the control unit adjusts the position of the contact member in accordance with the change in the shape of the workpiece due to the temperature change, based on the temperature of the workpiece detected by the temperature detection unit, by the operation of the drive unit.

9. The transfer robot according to claim 1, wherein the hand includes a pair of hands, and the contact member contacts the held workpiece in at least one of the pair of hands.

10. The transport robot according to claim 1, wherein the robot arm includes a horizontally articulated robot arm.

11. The transfer robot according to claim 1, wherein the robot arm includes a pair of robot arms, and the contact member contacts the held workpiece in the hand, which is positioned at the tip of at least one of the pair of robot arms.

12. The transport robot according to claim 1, wherein the drive unit includes a servo motor, and the control unit determines at least one of the workpiece state and the wear state based on the detection result of the contact state of the contact member that moves due to the operation of the servo motor.

13. The transport robot according to claim 12, wherein the detection unit includes a position detection unit that detects the position of the contact member as the contact state of the contact member, and the position detection unit includes an encoder that detects the rotation of the servo motor, and the position of the contact member is detected by detecting the rotation of the servo motor.

14. The transport robot according to claim 12, wherein the drive unit includes a linear motion mechanism that converts the rotation of the servo motor into linear motion, and the linear motion mechanism has a ball screw.

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