Substrate conveyance robot and control method for substrate conveyance robot

Abstract

A substrate conveyance robot (100) comprises: a hand (10) including blade sections (11) that hold a substrate (101); and at least four detection sections (14) that detect the substrate (101) and are disposed closer to the proximal end of the blade sections (11) than to the center (P) between the distal end and proximal end thereof.

Description

Substrate transport robot and method for controlling substrate transport robot

[0001] The present disclosure relates to a substrate transfer robot and a method for controlling the substrate transfer robot.

[0002] Conventionally, substrate transfer robots have been disclosed. The substrate transfer robot disclosed in U.S. Patent Application Publication No. 2016 / 0133502 includes a hand for holding a substrate and an arm for moving the hand. In U.S. Patent Application Publication No. 2016 / 0133502, the hand has a bifurcated Y-shape. Three sensors are disposed on the hand. The three sensors are reflective sensors that emit light toward the substrate and receive light reflected by the substrate. In U.S. Patent Application Publication No. 2016 / 0133502, one sensor is disposed at the bifurcated portion of the hand, and the remaining two sensors are disposed closer to the base end than the one sensor. In U.S. Patent Application Publication No. 2016 / 0133502, the hand is moved to enter a cassette in which a substrate is placed, and the edge of the substrate is detected by the one sensor at the tip end. The hand is then moved further into the cassette, and the edge of the substrate is detected by the two sensors at the base end. The hand movement ends when the two sensors on the base end detect the edge of the board. If the two sensors on the base end detect the edge of the board simultaneously, the hand's entry position relative to the board is determined to be normal. On the other hand, if the two sensors on the base end detect the edge of the board at different times, the hand's entry position relative to the board is determined to be abnormal.

[0003] US Patent Application Publication No. 2016 / 0133502

[0004] Here, if three sensors are arranged on the hand as disclosed in U.S. Patent Application Publication No. 2016 / 0133502, the position of the substrate can be accurately detected from the detection results of the three sensors. However, substrates such as semiconductor wafers may have a notch, which is a V-shaped depression, or an orientation flat, which is a flat portion, formed thereon so that the crystal orientation of the semiconductor wafer can be determined. When light is emitted from one of the three sensors toward the notch or orientation flat, the light is not reflected from the substrate, and the position of the substrate cannot be accurately detected using only the reflected light detected by the remaining two sensors. Therefore, there is a need for a substrate transfer robot that can accurately detect substrates even when a depression or the like is formed in the substrate.

[0005] This disclosure has been made to solve the above-mentioned problems, and one object of this disclosure is to provide a substrate transport robot and a control method for a substrate transport robot that can accurately detect a substrate even if a dent or the like is formed in the substrate.

[0006] A substrate transport robot according to a first aspect of this disclosure comprises a hand including a blade portion that holds a substrate, and four or more detection units that are positioned closer to the base end of the blade portion than the center between the tip and base end of the blade portion and detect the substrate.

[0007] As described above, the substrate transfer robot according to a first aspect of this disclosure includes four or more detectors disposed on the blade portion closer to the base end than the center between the tip and base ends of the blade portion to detect the substrate. As a result, even if one of the four or more detectors is unable to detect the substrate due to a dent or the like, the remaining three or more detectors can still detect the substrate. As a result, the substrate can be accurately detected even if a dent or the like is formed on the substrate. Furthermore, the four or more detectors are disposed on the blade portion closer to the base end than the center between the tip and base ends of the blade portion. This prevents the thickness of the tip side of the blade portion from increasing compared to when the detectors are disposed on the tip side of the blade portion. Therefore, even when multiple substrates are stacked at a relatively narrow interval, the tip side of the blade portion can be inserted between the substrates while avoiding interference between the substrates and the detectors.

[0008] A control method for a substrate transport robot according to a second aspect of this disclosure includes inserting a hand, which is positioned closer to the base end of the blade portion than the center between the tip and base end of the blade portion and has four or more detection units for detecting substrates, into a substrate mounting portion on which multiple substrates are stacked, and detecting the substrates using the four or more detection units.

[0009] A control method for a substrate transport robot according to a second aspect of this disclosure includes detecting a substrate using four or more detectors disposed on the blade portion closer to the base end than the center between the tip and base ends of the blade portion, as described above. As a result, even if one of the four or more detectors cannot detect the substrate due to a dent or the like, the substrate can be detected by the remaining three or more detectors. As a result, a control method for a substrate transport robot capable of accurately detecting a substrate even if a dent or the like is formed in the substrate can be provided. Furthermore, the four or more detectors are disposed on the blade portion closer to the base end than the center between the tip and base ends of the blade portion. This prevents the thickness of the tip side of the blade portion from increasing compared to when the detectors are disposed on the tip side of the blade portion. Therefore, a control method for a substrate transport robot can be provided that allows the tip side of the blade portion to enter between substrates while avoiding interference between the substrates and the detectors, even when multiple substrates are stacked at a relatively narrow interval.

[0010] According to the present disclosure, even if a dent or the like is formed in the substrate, the substrate can be accurately detected.

[0011] FIG. 1 is a schematic diagram showing the configuration of a substrate processing system including a substrate transfer robot according to an embodiment; FIG. 2 is a block diagram showing the configuration of a substrate transfer robot; FIG. 3 is a plan view for explaining the configuration of a hand of the substrate transfer robot; FIG. 4 is a side view for explaining the configuration of a hand of the substrate transfer robot; FIG. 5 is a diagram showing the configuration of a detection unit, and detection light emitted from the detection unit and reflected by a substrate; FIG. 6 is a flow diagram for explaining a control method of a substrate transfer robot according to an embodiment; FIG. 7 is a diagram showing a substrate placement unit and a substrate accommodated on the substrate placement unit; FIG. 8 is a diagram showing a state in which the detection unit and a notch of a substrate overlap; FIG. 9 is a diagram showing a hand according to a first modified example; FIG. 10 is a diagram showing a hand according to a second modified example; FIG. 11 is a diagram showing a hand according to a third modified example; FIG. 12 is a diagram showing a hand according to a fourth modified example; FIG. 13 is a diagram showing a hand according to a fifth modified example; and FIG. 14 is a diagram showing a substrate transfer robot according to a modified example.

[0012] Hereinafter, an embodiment of the present disclosure will be described with reference to the drawings.

[0013] The substrate transport robot 100 according to this embodiment will be described.

[0014] In this specification, the up-down direction is referred to as the Z direction. The upward direction is referred to as the Z1 direction, and the downward direction is referred to as the Z2 direction. The direction perpendicular to the Z direction is referred to as the X direction. One side of the X direction is referred to as the X1 direction, and the other side is referred to as the X2 direction. The direction perpendicular to the Z direction and the X direction is referred to as the Y direction. One side of the Y direction is referred to as the Y1 direction, and the other side is referred to as the Y2 direction. The direction in which the hand 10, which will be described later, extends is referred to as the A direction. The tip side of the hand 10 is referred to as the A1 direction, and the base end side is referred to as the A2 direction.

[0015] (Substrate Processing System) As shown in FIG. 1 , the substrate transfer robot 100 is disposed in a substrate processing system 102. The substrate processing system 102 includes the substrate transfer robot 100 and a processing device 103. The substrate transfer robot 100 performs a transfer operation that includes both loading and unloading of a substrate 101 onto and from a substrate placement unit 104 of the processing device 103. The substrate transfer robot 100 may be disposed in an atmospheric environment or a vacuum environment. Furthermore, if the substrate transfer robot 100 is disposed in a vacuum environment, a passive hand that does not require power to hold the substrate 101, such as the hand 10 described below, is desirable. This is because if a drive source that generates power to hold the substrate 101 is disposed outside the hand 10, heat from the drive source will be a factor, and the drive source must be able to withstand a vacuum environment. The processing device 103 includes multiple substrate placement units 104. The substrate transfer robot 100 includes the hand 10 that holds the substrate 101. The substrate 101 is, for example, a wafer for producing a semiconductor. The substrate 101 has a disk shape. The substrate 101 includes, for example, a silicon wafer, a gallium nitride wafer, a sapphire wafer, etc. The processing device 103 is, for example, a polishing device that polishes the substrate 101. The processing device 103 may also be a device that performs processing such as etching or baking on the substrate 101. If the substrate 101 is a wafer, for example, as shown in FIG. 3 , a notch 101 a, which is a V-shaped depression, is formed so that the crystal orientation of the wafer can be determined. Also, a flat portion, an orientation flat (not shown), is formed on the substrate 101 so that the crystal orientation of the wafer can be determined.

[0016] The substrate transport robot 100 includes a hand 10, an arm 30, an arm support unit 50, a lifting unit 60, and a control unit 70. In the substrate transport robot 100, the hand 10 is supported by the arm 30 and the arm support unit 50.

[0017] The arm 30 is a horizontally articulated robot arm that moves the hand 10 horizontally. The hand 10 is disposed at the tip of the arm 30. The hand 10 rotates horizontally relative to the arm 30. The arm 30 is connected to the Z1 side, which is above the arm support unit 50. As shown in FIG. 2 , the arm 30 has a drive unit 30a that rotates the joint. The drive unit 30a includes, for example, a servo motor. The drive unit 30a also has a transmission mechanism, such as a timing belt or gear, that transmits the driving force of the motor. The drive unit 30a also includes an encoder and a reducer. The drive unit 30a is disposed, for example, inside the housing of the arm 30 or inside the housing of the arm support unit 50.

[0018] 1, the arm 30 rotates around an axis ax relative to the arm support part 50 along a horizontal plane, which is the X-Y plane. The hand 10 moves linearly relative to the arm 30 along direction A, which is the direction in which the hand 10 extends.

[0019] (Specific Configuration of Hand) Next, the configuration of the hand 10 will be described. In this embodiment, as shown in FIG. 3 , the hand 10 is a passive hand. That is, the substrate 101 is held by being placed on the surface of a blade portion 11 (described later) of the hand 10. The substrate 101 is, for example, a wafer for producing semiconductors. The substrate 101 has a disk shape. The substrate 101 includes, for example, a silicon wafer, a gallium nitride wafer, a sapphire wafer, etc. The processing device 103 is, for example, a device that performs processing such as polishing, etching, or baking on the substrate 101.

[0020] The following describes the components of the hand 10. As shown in FIG. 3, the hand 10 includes a blade unit 11, a blade support unit 12, a substrate support unit 13, and a detection unit 14.

[0021] The configuration of the blade portion 11 will be described. The blade portion 11 is a member that holds the substrate 101. Specifically, the blade portion 11 has a bifurcated shape including a pair of claw portions 11a that hold the substrate 101 and a connecting portion 11b that connects the pair of claw portions 11a. The pair of claw portions 11a have the same shape. The claw portions 11a have a rectangular parallelepiped shape. The claw portions 11a also have a rod shape extending along the A direction. The claw portions 11a also have a thin plate shape. The claw portions 11a are formed, for example, from ceramics. Ceramics are a material that has high rigidity and heat resistance. The claw portions 11a may also be formed from metal or the like. The connecting portion 11b has a thin plate shape. In this embodiment, the connecting portion 11b has an arc shape. Specifically, an edge 11c on the A1 side, which is the tip side of the connecting portion 11b, has an arc shape. Furthermore, the edge 11d on the A2 side, which is the base end side of the connecting portion 11b, has a curved shape that includes a straight portion. Furthermore, the connecting portion 11b has an arc shape that widens toward the tip end when viewed from the Z direction. Furthermore, the connecting portion 11b is formed, for example, from aluminum or the like. Note that the shapes and materials of the claw portion 11a and the connecting portion 11b described above are merely examples and are not limited to the shapes and materials described above. As described above, the hand 10 is a passive hand and does not have an edge grip or the like for fixing the substrate 101, as in an active hand. Therefore, the thickness of the blade portion 11 is relatively small. Furthermore, a passive hand is particularly effective for transporting substrates 101 with special shapes, such as warped ones. Specifically, the processing of the substrate 101 is becoming increasingly multilayered, miniaturized, and dense. As a result, warping of the substrate 101 is more likely to occur. Therefore, a passive hand capable of transporting warped substrates 101 is required. Since the substrate 101 is simply placed on the passive hand, even a warped substrate 101 can be transported.

[0022] The distance D between the pair of claw portions 11a will be described. In this embodiment, the distance D between the pair of claw portions 11a is 60% or more and 100% or less of 2R, which is the diameter of the disk-shaped substrate 101. R is the radius of the substrate 101. In FIG. 3 , as an example, the distance D between the pair of claw portions 11a is less than 100% of 2R, which is the diameter of the substrate 101. In other words, when viewed from the Z direction, the pair of claw portions 11a are located more inward than the end of the substrate 101. Since the distance D between the pair of claw portions 11a is 60% or more of the diameter of the disk-shaped substrate 101, the distance D is larger than the radius R of the substrate 101. Furthermore, since the distance D is 100% or less of 2R, which is the diameter of the substrate 101, the substrate 101 is always supported from below by the pair of claw portions 11a.

[0023] The configuration of the blade support section 12 will be described. The blade support section 12 is connected to the base end of the blade section 11 and is a member that supports the blade section 11. The blade support section 12 is also connected to the arm 30 and moves linearly relative to the arm 30 in the direction A.

[0024] The configuration of the substrate support portion 13 will be described. The substrate support portion 13 supports the substrate 101 from below. Specifically, the substrate support portion 13 is disposed on the A1 side, which is the tip side of each of the pair of claw portions 11a. In FIG. 3, as an example, the substrate support portion 13 is disposed near the tip of each of the pair of claw portions 11a. More specifically, the substrate support portion 13 is disposed at a position slightly closer to the base end than the tip of the claw portion 11a. As shown in FIG. 4, the substrate support portion 13 has, for example, a hemispherical shape that protrudes toward the Z1 side. In other words, the surface of the substrate support portion 13 on the Z1 side, which is the side that supports the substrate 101, has a curved surface. The substrate support portion 13 is formed, for example, from ceramics.

[0025] The configuration of the detection unit 14 will be described. In this embodiment, as shown in FIG. 3 , the detection unit 14 is disposed in the blade portion 11 closer to the base end than the center P between the tip and base ends of the blade portion 11. The detection unit 14 detects the substrate 101. Four or more detection units 14 are disposed. Note that the following describes an example in which four detection units 14 are disposed. The detection unit 14 is disposed closer to the base end than the center P between the tip of the claw portion 11a, which is the tip of the blade portion 11, and the base end of the connection portion 11b, which is the base end of the blade portion 11. Disposed closer to the base end than the center P means that the detection unit 14 is disposed on the A2 side of the dotted line along the B direction indicating the center P shown in FIG. 3 .

[0026] 5, each of the four detectors 14 includes a reflective optical sensor that emits detection light toward the substrate 101 and detects light reflected by the substrate 101. Specifically, each of the four detectors 14 includes an emitter 14a that emits detection light, a light-receiving unit 14b that receives light reflected by the substrate 101, and a main body 14c. The emitter 14a and the light-receiving unit 14b are disposed on the A1 side, which is the tip side, of the main body 14c. When the blade portion 11 is disposed along the X-Y plane, the emitter 14a emits detection light toward the Z1 side. The light-receiving unit 14b receives light reflected by the substrate 101 and traveling toward the Z2 side. The detection results detected by the light-receiving unit 14b are transmitted to the control unit 70. The detection results are transmitted to the control unit 70 via signal lines arranged inside the hand 10, the arm 30, the arm support unit 50, and the lifting unit 60, for example. Furthermore, the A2 side portion of the main body 14c of each of the four detection units 14 is arranged inside the connection unit 11b. That is, the tip side of the main body 14c protrudes from the edge 11c of the connection unit 11b, and the light emitting unit 14a and the light receiving unit 14b are arranged in the portion of the main body 14c protruding from the edge 11c of the connection unit 11b. Furthermore, the main body 14c of each of the four detection units 14 is arranged along the A direction.

[0027] In this embodiment, as shown in FIG. 3 , the four detectors 14 are arranged along the edge 11c of the connecting portion 11b. Specifically, the light-emitting portion 14a and the light-receiving portion 14b of each of the four detectors 14 are arranged along the arc-shaped edge 11c on the A1 side of the connecting portion 11b. When viewed from a direction perpendicular to the surface of the blade portion 11, the four detectors 14 are arranged on two sides, one on the B1 side and the other on the B2 side, with respect to the center line L of the blade portion 11, which is along the A direction in which the blade portion 11 extends. Here, the surface of the blade portion 11 refers to the surface facing the substrate 101 when the substrate 101 is placed on the blade portion 11. Furthermore, the direction perpendicular to the surface of the blade portion 11 refers to the Z direction when the blade portion 11 is arranged along the X-Y plane. Furthermore, the center line L of the blade portion 11, which is along the A direction in which the blade portion 11 extends, is a line that passes through the center of the hand 10 in the B direction, which is the width direction of the hand 10, and is along the A direction. The A direction and the B direction are perpendicular to each other. One side of the B direction is the B1 direction, and the other side is the B2 direction. Two detectors 14 are arranged on either side of the center line L. The four detectors 14 are arranged symmetrically with respect to the center line L. The four detectors 14 are arranged spaced apart from each other.

[0028] In this embodiment, the four detectors 14 are arranged along the edge 11c of the connecting portion 11b between the pair of claws 11a. Specifically, when viewed from a direction perpendicular to the surface of the blade portion 11, the four detectors 14 are arranged between the pair of claws 11a. The pair of claws 11a are arranged at both ends of the connecting portion 11b in direction B. The four detectors 14 are arranged inward from both ends of the connecting portion 11b. As a result, the four detectors 14 are arranged between the pair of claws 11a.

[0029] In this embodiment, the four detection units 14 are arranged along a circumference having a radius within a range of ±10% of the radius R of the disk-shaped substrate 101. FIG. 3 shows, as an example, an example in which the four detection units 14 are arranged along the circumference of the disk-shaped substrate 101 having the radius R. In this example, the four detection units 14 are arranged along the edge of the disk-shaped substrate 101 when viewed from a direction perpendicular to the surface of the blade portion 11. In FIG. 3 , a circle C1 on the outside of the substrate 101 has a radius of 1.1 times the radius R of the substrate 101. A circle C2 on the inside of the substrate 101 has a radius of 0.9 times the radius R of the substrate 101.

[0030] In this embodiment, the four detectors 14 are arranged closer to the base end of the blade portion 11 than the board support portions 13. Specifically, the board support portions 13 are arranged near the tips of the claw portions 11a. The four detectors 14 are arranged at the connection portions 11b to which the base ends of the claw portions 11a are connected. That is, the four detectors 14 are arranged at the connection portions 11b, which are located closer to the base end than the board support portions 13 arranged near the tips of the claw portions 11a.

[0031] As shown in FIG. 1 , the lifting unit 60 moves the arm support unit 50 up and down, thereby moving the hand 10 up and down in the Z direction. The lifting unit 60 linearly slides the arm support unit 50 along the Z direction. Note that the term "sliding movement" used here does not refer to linear movement of the arm support unit 50 by the operation of link members that rotate relative to each other, but rather refers to linear movement of the arm support unit 50 sliding along a casing 61, which is a linearly extending columnar member. In other words, the sliding movement refers to linear movement of the lifting unit 60 along the casing 61, which is a linearly arranged member. Specifically, the arm 30 is connected to the lifting unit 60 via the arm support unit 50. The lifting unit 60 moves the arm support unit 50 up and down, thereby moving the arm 30, to which the hand 10 is connected, up and down. The lifting unit 60 has a columnar casing 61 that extends along the Z direction. The lifting unit 60 moves the arm support unit 50 up and down along the housing 61. As shown in FIG. 2 , the lifting unit 60 also includes a drive unit 60a. The drive unit 60a includes, for example, a servo motor as a drive source. The drive unit 60a also includes, for example, a ball screw mechanism and a linear guide. The arm support unit 50 is connected to the X1-side side of the lifting unit 60, and the drive force of the drive unit 60a moves the arm support unit 50 up and down in the Z direction.

[0032] The control unit 70 is a robot controller that controls the operation of each part of the substrate transfer robot 100. The control unit 70 includes, for example, a calculation device such as a central processing unit (CPU). The control unit 70 also includes memories such as a random access memory (RAM) and a read-only memory (ROM), and a storage device such as a hard disk. The control unit 70 executes control processing using the calculation device based on programs and parameters stored in the storage device. Specifically, the control unit 70 controls the operation of the drive unit 30a of the arm 30 and the drive unit 60a of the lifting unit 60. For example, the control unit 70 includes a main CPU that performs overall control of the substrate transfer robot 100 and a servo CPU that controls the power supplied to the servo motors of the drive units 30a and 60a. 1, the control unit 70 is disposed, for example, separately from the hand 10, the arm 30, and the lifting unit 60, and is connected to a housing 61 of the lifting unit 60 via a cable member. The control unit 70 outputs signals for controlling the operation of each unit via the cable member connected to the lifting unit 60.

[0033] The control unit 70 executes a transport operation of the substrate 101 based on a control amount that has been taught and set in advance. The control unit 70 controls the substrate transport robot 100 to, for example, access a substrate placement unit 104 that accommodates a plurality of substrates 101 and hold the substrate 101 in the hand 10. The control unit 70 also causes the hand 10 to hold the held substrate 101, thereby performing a transport operation of transporting the held substrate 101 from one substrate placement unit 104 to another substrate placement unit 104.

[0034] In this embodiment, the control unit 70 detects the position of the substrate 101 based on the detection results from the four detection units 14. The operation of the control unit 70 will be described below. In step S1 shown in FIG. 6 , as shown in FIG. 7 , the control unit 70 moves the arm 30 to move the hand 10 toward the substrate placement unit 104, thereby inserting the hand 10 into the substrate placement unit 104. In the substrate placement unit 104, multiple substrates 101 are stacked along the Z direction. In step S2, the control unit 70 causes the detection unit 14 to detect the substrate 101. Specifically, when the detection unit 14 and the substrate 101 overlap as viewed from the Z direction, the light receiving unit 14b of the detection unit 14 overlapping the substrate 101 receives detection light from the substrate 101. In step S3, the control unit 70 calculates the coordinates of the center C of the substrate 101 based on the detection results of at least three of the four detection units 14. The detection result of the detection unit 14 includes the detection time, etc., and the control unit 70 calculates the coordinate of the center C of the substrate 101 based on the posture of the arm 30 at the time of detection, the detection result of the detection unit 14, etc. As described above, the substrate 101 is formed with a notch 101a, an orientation flat, etc. As shown in FIG. 8 , if one of the four detection units 14 overlaps the notch 101a when viewed from the Z direction, reflected light from the substrate 101 is detected only by three detection units 14. However, it is possible to calculate the coordinate of the center C of the substrate 101 based on the detection results of at least three detection units 14. Therefore, by arranging four detection units 14, it is possible to calculate the coordinate of the center C of the substrate 101 even if the substrate 101 has a notch 101a or an orientation flat. The center of the substrate 101 can be determined, for example, as follows. First, three coordinates of the edges of the substrate 101 are detected. Next, two chords connecting two of the three coordinates are determined. Next, the perpendicular bisectors of the two chords are determined. The intersection of the perpendicular bisectors is the center of the circle. Alternatively, the coordinates of the center C of the substrate 101 may be calculated for each combination of three of the four detectors 14, and the average of the calculated coordinates may be calculated.Then, the deviation between this average value and the coordinates of the center C of the substrate 101, which serves as a reference, may be calculated.

[0035] Next, in step S4, the control unit 70 moves the hand 10 so that the hand 10 can properly hold the substrate 101 based on the calculated coordinates of the center C of the substrate 101, and causes the hand 10 to hold the substrate 101.

[0036] Next, in step S5, the hand 10 is moved, and the substrate 101 held by the hand 10 is placed on another substrate placement unit 104, etc. Note that if the distance D between the pair of claws 11a is relatively large, the gap between the claws 11a and the substrate placement unit 104 is small, and therefore, in step S4, it may be difficult to move the hand 10 so that the hand 10 can appropriately hold the substrate 101 within the substrate placement unit 104 based on the calculated coordinates of the center C of the substrate 101. Therefore, in step S4, the control unit 70 may move the hand 10 as instructed in advance to hold the substrate 101, and then place the substrate 101 at an appropriate position based on the calculated coordinates of the center C of the substrate 101. In other words, when the substrate 101 is held and moved, the substrate 101 may be displaced from a reference position relative to the hand 10, and when the substrate 101 is placed, the substrate 101 may be placed at an appropriate position based on the calculated coordinates of the center C of the substrate 101. The operations from steps S1 to S5 are repeated until the transfer of all of the plurality of substrates 101 is completed.

[0037] In the case of an edge-grip hand, the edge-grip hand grips the substrate 101, thereby allowing the substrate 101 to be aligned on the edge-grip hand. On the other hand, a passive hand or suction hand such as the hand 10 cannot align the substrate 101 on the hand by simply gripping it like the edge-grip hand. For this reason, the control unit 70 needs to detect any misalignment of the substrate 101 on the hand 10 based on the detection results from the four detection units 14.

[0038] [Effects of this embodiment] The effects of the hand 10 will be described below.

[0039] The substrate transfer robot 100 includes four or more detectors 14 disposed closer to the base end of the blade unit 11 than the center P between the tip and base ends of the blade unit 11 and configured to detect the substrate 101. As a result, even if one of the four or more detectors 14 is unable to detect the substrate 101 due to a dent or the like, the remaining three or more detectors 14 can still detect the substrate 101. As a result, the substrate 101 can be accurately detected even if a dent or the like is formed on the substrate 101. Furthermore, the four or more detectors 14 are disposed closer to the base end of the blade unit 11 than the center P between the tip and base ends of the blade unit 11. As a result, the thickness of the tip side of the blade unit 11 is prevented from increasing compared to when the detectors 14 are disposed closer to the tip side of the blade unit 11. Therefore, even when multiple substrates 101 are stacked at relatively narrow intervals, the tip side of the blade unit 11 can be inserted between the substrates 101 while avoiding interference between the substrates 101 and the detectors 14.

[0040] The blade portion 11 has a bifurcated shape having a pair of claw portions 11a that hold the substrate 101 and a connecting portion 11b that connects the pair of claw portions 11a, and the four or more detecting portions 14 are arranged along an edge 11c of the connecting portion 11b. This makes it possible to easily arrange the four or more detecting portions 14 on the connecting portion 11b, which is the base end side of the blade portion 11. Furthermore, because the four or more detecting portions 14 are arranged along the edge 11c of the connecting portion 11b, the edge of the substrate 101 can be easily detected by the four or more detecting portions 14.

[0041] The connecting portion 11b has an arc shape, and the four or more detecting portions 14 are arranged along the edge 11c of the arc-shaped connecting portion 11b. As a result, even if the substrate 101 has an arc-shaped edge 11c such as a disk shape, the edge of the substrate 101 can be easily detected by the four or more detecting portions 14 arranged along the edge 11c of the arc-shaped connecting portion 11b.

[0042] The four or more detectors 14 are arranged along the edge 11 c of the connecting portion 11 b between the pair of claws 11 a, thereby preventing the detection operation of the detectors 14 from being hindered by the claws 11 a.

[0043] The substrate 101 has a disk shape, and the distance D between the pair of claw portions 11a is 60% or more and 100% or less of 2R, which is the diameter of the disk-shaped substrate 101. As a result, the distance D between the pair of claw portions 11a does not exceed 2R, which is the diameter of the substrate 101, so the pair of claw portions 11a can reliably hold the substrate 101. Furthermore, because the distance D between the pair of claw portions 11a is 60% or more of 2R, which is the diameter of the disk-shaped substrate 101, the distance D between the pair of claw portions 11a becomes relatively large. Therefore, the pair of claw portions 11a can stably hold the substrate 101.

[0044] The four or more detection units 14 are arranged separately on one side and the other side of the center line L of the blade unit 11, which is along the extension direction of the blade unit 11, when viewed from a direction perpendicular to the surface of the blade unit 11. As a result, the four or more detection units 14 are sparsely arranged, which can improve the accuracy of detection of the substrate 101 compared to when the four or more detection units 14 are densely arranged.

[0045] The substrate 101 has a disk shape, and the four or more detection units 14 are arranged along a circumference having a radius within a range of ±10% of the radius R of the disk-shaped substrate 101. As a result, the four or more detection units 14 are arranged along the edge of the disk-shaped substrate 101, and the edge of the substrate 101 can be properly detected by the four or more detection units 14.

[0046] The hand 10 includes a substrate support section 13 that supports the substrate 101 from below, and the four or more detection sections 14 are arranged closer to the base end of the blade section 11 than the substrate support section 13. This makes it possible to suppress interference between the detection sections 14 and the substrate 101, unlike when the four or more detection sections 14 are arranged closer to the tip end of the blade section 11 than the substrate support section 13.

[0047] The hand 10 includes a passive hand that holds the substrate 101 by placing the substrate 101 on the surface of the blade portion 11. As a result, the passive hand does not have a mechanism for holding the substrate 101 on the surface of the substrate 101, as in the active hand, and is therefore relatively thin. Therefore, even when multiple substrates 101 are stacked at relatively narrow intervals, the blade portion 11 can easily be inserted between the substrates 101.

[0048] Each of the four or more detection units 14 includes a reflective optical sensor that emits detection light to the substrate 101 and detects light reflected by the substrate 101. As a result, even if the light emitted from one of the four or more detection units 14 is not reflected by passing through a recess or the like, the substrate 101 can be detected by the light emitted from the remaining three or more detection units 14.

[0049] The substrate transport robot 100 includes a control unit 70 that detects the position of the substrate 101 based on detection results from four or more detection units 14. Here, in order to accurately detect the position of the substrate 101, it is necessary to detect three or more points on the substrate 101. In this embodiment, since four or more detection units 14 are arranged, even if a depression or the like is formed in the substrate 101 and one detection unit 14 cannot detect the substrate 101, the position of the substrate 101 can be accurately detected based on the detection results of the remaining three or more detection units 14.

[0050] The control method for the substrate transport robot 100 includes moving the hand 10 to hold the substrate 101 based on the detection result of the detection unit 14, or holding the substrate 101 with the hand 10 and then placing the substrate 101 held by the hand 10 based on the detection result of the detection unit 14. This makes it possible to appropriately hold the substrate 101 with the hand 10 or appropriately place the substrate 101 based on the detection result of the detection unit 14.

[0051] Furthermore, in the substrate processing system 102, an aligner is generally used to detect the notch and orientation flat of the substrate 101 and perform a process of rotational alignment of the substrate 101 and a process of centering the substrate 101. Note that when processing the substrate 101 in a vacuum environment, the rotational position of the substrate 101 may not be important. In this case, the process of rotational alignment of the substrate 101 is unnecessary. In this case, as in the present embodiment, the control unit 70 can detect the center of the substrate 101 based on the detection results from the four detection units 14, making it possible to eliminate the need for an aligner.

[0052] [Modifications] The embodiments disclosed herein should be considered to be illustrative and not restrictive in all respects. The scope of the present disclosure is defined by the claims, not by the description of the above-mentioned embodiments, and includes all modifications (modifications) within the meaning and scope of the claims.

[0053] For example, in the above embodiment, an example has been shown in which the arm 30, which is a horizontally articulated robot arm, is raised and lowered by the lifting unit 60 in the substrate transport robot 100, but the present disclosure is not limited to this. For example, the present disclosure may be applied to a substrate transport robot in which a horizontally articulated robot arm is connected to a base placed on the floor surface and does not rise and fall.

[0054] In the above embodiment, the substrate 101 is a semiconductor wafer having a disk shape, but the present disclosure is not limited to this. For example, the present disclosure can be applied to a substrate transport robot that transports a rectangular substrate or a substrate other than a semiconductor wafer.

[0055] In addition, in the above embodiment, an example in which four detection units 14 are arranged on the hand 10 has been described, but the present disclosure is not limited to this. For example, five or more detection units 14 may be arranged on the hand 10. Furthermore, the numbers of detection units 14 arranged on the hands 10 may differ from one another.

[0056] In the above embodiment, the blade portion 11 includes the claw portion 11a and the connecting portion 11b made of different materials, but the present disclosure is not limited to this. For example, the blade portion 11 may include the claw portion 11a and the connecting portion 11b made of the same material. Furthermore, the claw portion 11a and the connecting portion 11b made of the same material may be integrally formed.

[0057] In the above embodiment, the connecting portion 11b of the detecting portion 14 has an arc shape, but the present disclosure is not limited to this. For example, the connecting portion 11b of the detecting portion 14 may have a rectangular shape.

[0058] In the above embodiment, the four detectors 14 are disposed on the connecting portion 11 b between the pair of claws 11 a, but the present disclosure is not limited to this. For example, as shown in a hand 120 of a first modified example in FIG. 9 , two of the four detectors 14 may be disposed on the connecting portion 11 b and the remaining two detectors 14 may be disposed on the claws 11 a.

[0059] In the above embodiment, the four detectors 14 are arranged two on each side of the center line L of the blade 11 when viewed from a direction perpendicular to the surface of the blade 11, but the present disclosure is not limited to this. For example, as shown in a hand 121 of a second modified example in Fig. 10 , of the four detectors 14, one detector 14 may be arranged on the B1 side of the center line L and the remaining three detectors 14 may be arranged on the B2 side.

[0060] In addition, although the above embodiment illustrates an example in which the four detectors 14 are arranged along the circumference, the present disclosure is not limited to this. For example, as shown in a hand 122 of a third modified example illustrated in Fig. 11, the four detectors 14 do not have to be arranged along the circumference. For example, the four detectors 14 may protrude from the connecting portion 11b toward the A1 side by different amounts.

[0061] In the above embodiment, the substrate support portion 13 is disposed near the tip of the claw portion 11 a, but the present disclosure is not limited to this. For example, the substrate support portion 13 may be disposed in the center of the claw portion 11 a.

[0062] Although the above embodiment illustrates an example in which the hand 10 is a passive hand, the present disclosure is not limited thereto. For example, as shown in FIG. 12 , the hand 123 may be a suction-type hand that suctions the substrate 101 onto the surface of the blade portion 123a. In the hand 123, a ventilation passage 123b through which air flows is formed inside the blade portion 123a, and the ventilation passage 123b is connected to an opening 123c on the surface of the blade portion 123a. The substrate 101 is suctioned by being sucked through the ventilation passage 123b. Like a passive hand, a suction-type hand does not have a mechanism for holding the substrate 101 on the surface of the substrate 101, as in an active hand, and therefore is relatively thin. Therefore, even when multiple substrates 101 are stacked at relatively narrow intervals, the blade portion 123a can easily be inserted between the substrates 101.

[0063] In the above embodiment, all four detection units 14 are reflective optical sensors, but the present disclosure is not limited to this. For example, all four detection units 14 may be transmissive optical sensors. Alternatively, some of the four detection units 14 may be reflective optical sensors and the rest may be transmissive optical sensors.

[0064] 13 , a wall 124a that restricts movement of the substrate 101 may be disposed on the base end side of the claw 11a. As a result, when the hand 124 moves in the A1 direction relative to the substrate 101, the substrate 101 abuts against the wall 124a. This positions the substrate 101 relative to the hand 124. The wall 124a protrudes from the claw 11a toward the Z1 side. The wall 124a has, for example, a rectangular shape when viewed from the Z direction, and is disposed on the claw 11a so that the wide surface of the wall 124a abuts against the substrate 101.

[0065] In the above embodiment, the control unit 70 detects the center of the substrate 101 based on the detection results from the four detection units 14. However, the present disclosure is not limited to this. For example, the control unit 70 may detect deviation of the substrate 101 from a predetermined position, tilt of the substrate 101, warpage of the substrate 101, etc. based on the detection results from the four detection units 14.

[0066] Furthermore, in the above embodiment, an example has been shown in which the substrate transfer robot 100 includes the lifting unit 60, the arm support unit 50 that is raised and lowered by the lifting unit 60, the arm 30 that rotates relative to the arm support unit 50, and the hand 10 that moves linearly relative to the arm 30, but the present disclosure is not limited to this. For example, as in a substrate transfer robot 200 according to a modified example shown in Fig. 14, the hand 10 of the present disclosure may be attached to a horizontally articulated arm unit 210 that includes two link units.

[0067] The functions of the elements disclosed herein can be performed using circuits or processing circuits, including general-purpose processors, special-purpose 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 circuitry. In this disclosure, a circuit, unit, or means is hardware that performs the recited functions or hardware that is programmed to perform the recited functions. The hardware may be hardware disclosed herein or other known hardware that is programmed or configured to perform the recited functions. Where the hardware is a processor, which is considered a type of circuit, the circuit, means, or unit is a combination of hardware and software, and the software is used to configure the hardware and / or processor.

[0068] Aspects It will be appreciated by those skilled in the art that the exemplary embodiments described above are examples of the following aspects.

[0069] (Aspect 1) A substrate transport robot comprising: a hand including a blade portion that holds a substrate; and four or more detection units that are positioned closer to the base end of the blade portion than the center between the tip and base end of the blade portion and that detect the substrate.

[0070] (Aspect 2) The substrate transport robot according to Aspect 1, wherein the blade portion has a bifurcated shape having a pair of claw portions that hold the substrate and a connecting portion that connects the pair of claw portions, and the four or more detection units are arranged along the edge of the connecting portion.

[0071] (Aspect 3) The substrate transfer robot according to aspect 2, wherein the connection portion has an arc shape, and the four or more detection portions are arranged along an edge of the arc-shaped connection portion.

[0072] (Aspect 4) The substrate transport robot according to aspect 2 or 3, wherein the four or more detectors are arranged along an edge of the connecting portion between the pair of claws.

[0073] (Aspect 5) The substrate transport robot according to any one of Aspects 2 to 4, wherein the substrate has a disk shape, and the distance between the pair of claw portions is 60% or more and 100% or less of the diameter of the disk-shaped substrate.

[0074] (Aspect 6) A substrate transport robot described in any one of Aspects 1 to 5, wherein the four or more detection units are arranged separately on one side and the other side of the center line of the blade unit along the direction in which the blade unit extends, when viewed from a direction perpendicular to the surface of the blade unit.

[0075] (Aspect 7) The substrate transport robot according to any one of Aspects 1 to 6, wherein the substrate has a disk shape, and the four or more detection units are arranged along a circumference having a radius within a range of ±10% of the radius of the disk-shaped substrate.

[0076] (Aspect 8) A substrate transport robot according to any one of Aspects 1 to 7, wherein the hand includes a substrate support portion that supports the substrate from below, and the four or more detection portions are positioned closer to the base end of the blade portion than the substrate support portion.

[0077] (Aspect 9) A substrate transport robot according to any one of Aspects 1 to 8, wherein the hand includes a passive hand that holds the substrate by placing the substrate on the surface of the blade portion, or a suction hand that suctions the substrate onto the surface of the blade portion.

[0078] (Aspect 10) The substrate transport robot according to any one of Aspects 1 to 9, wherein the four or more detection units each include a reflective optical sensor that emits detection light to the substrate and detects light reflected by the substrate.

[0079] (Aspect 11) The substrate transport robot according to any one of Aspects 1 to 10, further comprising a control unit that detects the position of the substrate based on detection results from the four or more detection units.

[0080] (Mode 12) A method for controlling a substrate transport robot, comprising: inserting a hand, which is positioned closer to the base end of a blade portion than the center between the tip and base end of the blade portion and has four or more detection units for detecting substrates, into a substrate mounting portion in which a plurality of the substrates are stacked; and detecting the substrates using the four or more detection units.

[0081] (Aspect 13) A method for controlling a substrate transport robot according to Aspect 12, comprising: moving the hand to hold the substrate based on the detection result of the detection unit; or holding the substrate with the hand, and then placing the substrate held by the hand based on the detection result of the detection unit.

Claims

1. A substrate transport robot comprising: a hand including a blade portion for holding a substrate; and four or more detection units arranged on the blade portion closer to the base end than the center between the tip and base end of the blade portion, for detecting the substrate.

2. A substrate transport robot as described in claim 1, wherein the blade portion has a bifurcated shape with a pair of claw portions that hold the substrate and a connecting portion that connects the pair of claw portions, and the four or more detection portions are arranged along the edge of the connecting portion.

3. The substrate transfer robot according to claim 2, wherein the connecting portion has an arc shape, and the four or more detecting portions are arranged along the edge of the arc-shaped connecting portion.

4. The substrate transport robot according to claim 2, wherein the four or more detection units are arranged along the edge of the connection unit between the pair of claw units.

5. The substrate transport robot according to claim 2, wherein the substrate has a disk shape, and the distance between the pair of claw portions is 60% or more and 100% or less of the diameter of the disk-shaped substrate.

6. A substrate transport robot as described in claim 1, wherein the four or more detection units are arranged separately on one side and the other side of the center line of the blade unit along the direction in which the blade unit extends, when viewed from a direction perpendicular to the surface of the blade unit.

7. A substrate transport robot as described in claim 1, wherein the substrate has a disk shape, and the four or more detection units are arranged along a circumference having a radius within a range of ±10% of the radius of the disk-shaped substrate.

8. A substrate transport robot as described in claim 1, wherein the hand includes a substrate support part that supports the substrate from below, and the four or more detection parts are positioned closer to the base end of the blade part than the substrate support part.

9. A substrate transport robot as described in claim 1, wherein the hand includes a passive hand that holds the substrate by placing the substrate on the surface of the blade portion, or an adsorption hand that adsorbs the substrate on the surface of the blade portion.

10. A substrate transport robot as described in claim 1, wherein each of the four or more detection units includes a reflective optical sensor that emits detection light to the substrate and detects light reflected by the substrate.

11. The substrate transport robot according to claim 1, further comprising a control unit that detects the position of the substrate based on the detection results from the four or more detection units.

12. A method for controlling a substrate transport robot, comprising: inserting a hand, which is positioned closer to the base end of the blade section than the center between the tip and base end of the blade section and has four or more detection units for detecting substrates, into a substrate placement section in which a plurality of the substrates are stacked; and detecting the substrates using the four or more detection units.

13. A method for controlling a substrate transport robot as described in claim 12, comprising: moving the hand to hold the substrate based on the detection result of the detection unit; or holding the substrate with the hand, and then placing the substrate held by the hand based on the detection result of the detection unit.

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