WO2024075839A1

WO2024075839A1 - Substrate-conveying robot system, and method for correcting position of substrate placement and/or position of substrate removal by substrate-conveying robot

Info

Publication number: WO2024075839A1
Application number: PCT/JP2023/036553
Authority: WO
Inventors: 武士芝田; 知橋崎
Original assignee: 川崎重工業株式会社
Priority date: 2022-10-07
Filing date: 2023-10-06
Publication date: 2024-04-11
Also published as: JP2024055616A

Abstract

In this substrate-conveying robot system (100), a control unit (13) acquires a center position (20a) of a target member (20) in a horizontal plane on the basis of: a first tangent (TL1) corresponding to an outer circumferential edge section (20b) of the target member (20), the first tangent (TL1) being acquired by using a detection unit (14) and causing a hand (12) to approach the target member (20) from a first direction in the horizontal plane; and a second tangent (TL2) corresponding to the outer circumferential edge section (20b) of the target member (20), the second tangent (TL2) being acquired by using the detection unit (14) and causing the hand (12) to approach the target member (20) from a second direction in the horizontal plane, the second direction differing from the first direction.

Description

Substrate transport robot system and method for correcting at least one of the placement and pick-up positions of a substrate by a substrate transport robot

This disclosure relates to a substrate transport robot system and a method for correcting at least one of the placement and pick-up positions of a substrate by a substrate transport robot.

　Substrate transport robots that correct the placement position of a substrate in a horizontal plane are known. For example, Japanese Patent Publication No. 6637494 discloses a substrate transport robot that corrects the placement position of a substrate in a horizontal plane based on the identified center position of a target in the horizontal plane and the relative positional relationship in the horizontal plane between the center position of the target and the placement location of the substrate that has been acquired in advance. The target is placed at a predetermined position relative to the placement location of the substrate in order to correct the placement position of the substrate in the horizontal plane.

The substrate transport robot disclosed in Patent Publication No. 6637494 locates the central position of a target in a horizontal plane as follows: First, a hand attached to the end of the robot arm is brought closer to the target until the target begins to be detected by the sensor. The hand is then swung. The hand offset amount is calculated based on the change in the sensor detection signal caused by swung the hand. The hand position is shifted based on the calculated offset amount. Then, the hand swing, calculation of the hand offset amount, shifting of the hand position, etc. are repeated until the central position of the target in the horizontal plane is identified.

Patent No. 6637494

However, in the substrate transport robot described in Patent No. 6637494, in order to identify the center position of the target in the horizontal plane, it is necessary to repeatedly swing the hand, calculate the offset amount of the hand, shift the position of the hand, etc., so it is thought that the time to identify the position of the target in the horizontal plane will be relatively long. In other words, it is thought that the time to correct the placement position of the substrate in the horizontal plane will be relatively long. Although not described in the above Patent Document 1, when correcting the pick-up position of the substrate in the horizontal plane in a substrate transport robot such as that described in Patent No. 6637494, the same problem as when correcting the placement position of the substrate in the horizontal plane is thought to occur. For this reason, a configuration that can shorten the time to correct at least one of the placement position and pick-up position of the substrate in the horizontal plane is desired.

This disclosure has been made to solve the problems described above, and one objective of this disclosure is to provide a substrate transport robot system that can shorten the time required to correct at least one of the placement position and pick-up position of a substrate in a horizontal plane, and a method for correcting at least one of the placement position and pick-up position of a substrate by a substrate transport robot.

In order to achieve the above object, a substrate transport robot system according to a first aspect of this disclosure includes a substrate transport robot that transports a substrate, a horizontal target member that has a circular shape when viewed from above and below and is used to correct at least one of the placement position and pick-up position of the substrate in a horizontal plane, and a control unit. The substrate transport robot includes a robot arm, a hand attached to the tip of the robot arm, and a detection unit that is disposed on the hand and detects the outer periphery of the horizontal target member. The control unit detects the horizontal target member obtained using the detection unit by bringing the hand close to the horizontal target member from a first direction in the horizontal plane. Based on a first tangent corresponding to the outer peripheral edge of the target member and a second tangent corresponding to the outer peripheral edge of the horizontal target member obtained using the detection unit by approaching the hand to the horizontal target member from a second direction in the horizontal plane different from the first direction, the center position of the horizontal target member in the horizontal plane is obtained, and at least one of the placement position and removal position of the substrate in the horizontal plane is corrected based on the obtained center position of the horizontal target member in the horizontal plane and the relative positional relationship in the horizontal plane between the center position of the horizontal target member and the placement location of the substrate that has been obtained in advance.

In the substrate transport robot system according to the first aspect of this disclosure, as described above, the control unit obtains the center position of the horizontal target member in the horizontal plane based on a first tangent corresponding to the outer periphery of the horizontal target member obtained by approaching the hand to the horizontal target member from a first direction in the horizontal plane and using the detection unit, and a second tangent corresponding to the outer periphery of the horizontal target member obtained by approaching the hand to the horizontal target member from a second direction in the horizontal plane different from the first direction and using the detection unit. As a result, if the first tangent and the second tangent are each obtained once, the center position of the horizontal target member can be obtained immediately based on the first tangent and the second tangent. In other words, the center position of the horizontal target member in the horizontal plane can be obtained quickly compared to the case where the hand is swung, the amount of the hand offset is calculated, the position of the hand is shifted, etc. are repeatedly performed to identify the center position of the target member in the horizontal plane. As a result, at least one of the placement position and the pick-up position of the substrate in the horizontal plane can be quickly corrected. As a result, the time required to correct at least one of the placement and removal positions of the substrate in the horizontal plane can be reduced.

Furthermore, in order to achieve the above object, a method for correcting at least one of the placement position and pick-up position of a substrate by a substrate transport robot according to a second aspect of this disclosure comprises a robot arm, a hand attached to the tip of the robot arm, and a detection unit that detects a horizontal target member having a circular shape when viewed from the top-bottom direction and for correcting at least one of the placement position and pick-up position of a substrate in a horizontal plane, and the method for correcting at least one of the placement position and pick-up position of a substrate by a substrate transport robot that transports a substrate comprises: a robot arm; a hand attached to the tip of the robot arm; and a detection unit that detects a horizontal target member having a circular shape when viewed from the top-bottom direction and for correcting at least one of the placement position and pick-up position of a substrate in a horizontal plane, the method comprising: bringing the hand close to the horizontal target member from a first direction in the horizontal plane; using the hand to obtain a first tangent to the outer periphery of the horizontal target member; bringing the hand close to the horizontal target member from a second direction in the horizontal plane different from the first direction and using the detector to obtain a second tangent to the outer periphery of the horizontal target member; obtaining a center position of the horizontal target member based on the obtained first tangent and the obtained second tangent; and correcting at least one of the placement position and removal position of the substrate in the horizontal plane based on the obtained center position and a relative positional relationship in the horizontal plane between the center position and the substrate placement location that has been obtained in advance.

In the method for correcting at least one of the placement position and pick-up position of a substrate by a substrate transport robot according to the second aspect of this disclosure, as described above, the hand is brought close to the horizontal target member from a first direction in a horizontal plane, and a first tangent to the outer periphery of the horizontal target member is obtained using the detection unit. Also, the hand is brought close to the horizontal target member from a second direction in the horizontal plane different from the first direction, and a second tangent to the outer periphery of the horizontal target member is obtained using the detection unit. Also, the center position of the horizontal target member is obtained based on the obtained first tangent and the obtained second tangent. As a result, similar to the substrate transport robot system according to the first aspect, once the first tangent and the second tangent are obtained, the center position of the horizontal target member can be obtained immediately based on the first tangent and the second tangent. As a result, similar to the substrate transport robot system according to the first aspect, the time required to correct at least one of the placement position and pick-up position of the substrate in the horizontal plane can be shortened.

According to the present disclosure, as described above, it is possible to provide a substrate transport robot system that can shorten the time required to correct at least one of the placement position and pick-up position of a substrate in a horizontal plane, and a method for correcting at least one of the placement position and pick-up position of a substrate by a substrate transport robot.

1 is a plan view showing an overall configuration of a substrate transport robot system according to an embodiment of the present disclosure. 1 is a perspective view showing a substrate transport robot according to an embodiment of the present disclosure; 11A and 11B are diagrams for explaining acquisition of a first tangent in a substrate transport robot system according to an embodiment of the present disclosure. 13A and 13B are diagrams for explaining acquisition of a second tangent in the substrate transport robot system according to the embodiment of the present disclosure. 11A and 11B are diagrams for explaining acquisition of the center position of a target member in a substrate transport robot system according to an embodiment of the present disclosure. 11A and 11B are diagrams for explaining acquisition of the position of a target member in the up-down direction in a substrate transport robot system according to an embodiment of the present disclosure. 13A and 13B are diagrams for explaining acquisition of the inclination of the coordinate system of a substrate placement location relative to the coordinate system of a robot arm in a substrate transport robot system according to an embodiment of the present disclosure. 13A and 13B are diagrams illustrating a state in which a direction in which a hand approaches a target member is not perpendicular to the direction of detection light in the substrate transport robot system according to the embodiment of the present disclosure. 13A and 13B are diagrams for explaining acquisition of the inclination in a direction perpendicular to the direction of the detection light with respect to the direction in which the hand approaches the target member in the substrate transport robot system according to the embodiment of the present disclosure. 11 is a diagram illustrating a state in which a direction in which a hand approaches a target member is perpendicular to the direction of detection light in the substrate transport robot system according to the embodiment of the present disclosure. FIG. FIG. 11 is a flow chart showing a correction flow for a substrate placement position in a substrate transport robot system according to an embodiment of the present disclosure.

Below, an embodiment of this disclosure will be described with reference to the drawings.

[Configuration of Substrate Transport Robot System]
The configuration of a substrate transport robot system 100 according to an embodiment of the present disclosure will be described with reference to FIGS. 1 to 10. FIG.

(Overall configuration of substrate transport robot system)
1, the substrate transport robot system 100 includes a substrate transport robot 10 and a target member 20. The target member 20 is an example of a horizontal target member, a first horizontal target member, and an upper and lower target member.

The substrate transport robot 10 is a robot that transports substrates W to a storage location 200 for substrates W. The storage location 200 for substrates W is, for example, a FOUP (Front Opening Unify Pod).

The target member 20 is a member for correcting the placement position PP of the substrate W in the horizontal plane and in the vertical direction by the substrate transport robot 10. That is, the target member 20 is a member for correcting the placement position PP of the substrate W to match the placement site 200 for the substrate W. The target member 20 is placed at a predetermined position relative to the placement site 200 for the substrate W. That is, the relative positional relationship in the horizontal plane between the center position 20a of the target member 20 and the placement site 200 for the substrate W does not change. The target member 20 has a circular shape when viewed from the vertical direction.

(Configuration of the substrate transport robot)
As shown in FIG. 2, the substrate transport robot 10 includes a robot arm 11, a hand 12, and a control unit 13.

The robot arm 11 is a horizontal multi-joint type robot arm. The robot arm 11 is controlled by the control unit 13 to operate multiple joints.

The control unit 13 controls the operation of the robot arm 11, the operation of the hand 12, etc. The control unit 13 includes a processor such as a CPU (Central Processing Unit) and memories such as a ROM (Read Only Memory) and a RAM (Random Access Memory).

The hand 12 is attached to the tip of the robot arm 11. The hand 12 holds the substrate W. The hand 12 includes a first tip 12a and a second tip 12b that are bifurcated.

As shown in FIG. 3, the robot arm 11 includes a detection unit 14. The detection unit 14 is a mapping sensor that detects the presence or absence of a substrate W in the substrate W storage area 200. The detection unit 14 is disposed on the hand 12. The detection unit 14 is a transmission sensor that detects the target member 20 based on whether or not the detection light DL passing through the space S between the first tip 12a and the second tip 12b is blocked. Note that while FIG. 3 shows an example in which the detection light DL travels from the second tip 12b side to the first tip 12a side, the detection light DL may travel from the first tip 12a side to the second tip 12b side.

(Correction of the horizontal position of the board)
As shown in Fig. 3, the control unit 13 causes the hand 12 to approach the target member 20 from a first direction in a horizontal plane, and obtains a first tangent TL1 (see Fig. 5) corresponding to the outer periphery 20b of the target member 20 using the detection unit 14. Specifically, the control unit 13 controls the operation of the robot arm 11 so that the hand 12 approaches the target member 20 from the first direction in a horizontal plane until the outer periphery 20b of the target member 20 is detected by the detection unit 14. Then, the control unit 13 obtains, as the first tangent TL1, a straight line along the direction of the detection light DL at the position of the hand 12 where the outer periphery 20b of the target member 20 is detected by the detection unit 14. The direction in which the hand 12 approaches the target member 20 is parallel to the Y direction of the coordinate system C1 of the robot arm 11.

Then, as shown in FIG. 4, the control unit 13 causes the hand 12 to approach the target member 20 from a second direction in the horizontal plane different from the first direction, and acquires a second tangent TL2 (see FIG. 5) corresponding to the outer periphery 20b of the target member 20 using the detection unit 14. Specifically, the control unit 13 controls the operation of the robot arm 11 so as to cause the hand 12 to approach the target member 20 from the second direction in the horizontal plane until the detection unit 14 detects the outer periphery 20b of the target member 20. The control unit 13 then acquires, as the second tangent TL2, a straight line along the direction of the detection light DL at the position of the hand 12 where the detection unit 14 detects the outer periphery 20b of the target member 20.

Then, as shown in FIG. 5, the control unit 13 obtains the center position 20a of the target member 20 in the horizontal plane based on the first tangent TL1 and the second tangent TL2. Specifically, the control unit 13 obtains the intersection of the perpendicular line PL1 of the first tangent TL1 and the perpendicular line PL2 of the second tangent TL2 as the center position 20a of the target member 20. Note that, in order to improve the accuracy of obtaining the center position 20a of the target member 20 in the horizontal plane, the control unit 13 may use, for example, the radius R of the target member 20 in addition to the first tangent TL1 and the second tangent TL2 when obtaining the center position 20a of the target member 20 in the horizontal plane.

Then, the control unit 13 corrects the placement position PP of the substrate W in the horizontal plane based on the acquired center position 20a of the target member 20 in the horizontal plane and the previously acquired relative positional relationship in the horizontal plane between the center position 20a of the target member 20 and the placement site 200 of the substrate W. Specifically, the control unit 13 corrects the placement position PP of the substrate W in the horizontal plane based on the acquired center position 20a of the target member 20 in the horizontal plane and the previously acquired relative positional relationship in the horizontal plane between the center position 20a of the target member 20 and the center position 200a of the placement site 200 of the substrate W. Note that the control unit 13 previously acquires the relative positional relationship in the horizontal plane between the center position 20a of the target member 20 and the center position 200a of the placement site 200 of the substrate W before correcting the placement position PP of the substrate W in the horizontal direction.

(Correction of the board placement position in the vertical direction)
6, the control unit 13 acquires the position 20c of the target member 20 in the vertical direction based on the timing at which the detection unit 14 switches between a state in which the target member 20 is detected in the vertical direction and a state in which the target member 20 is not detected in the vertical direction, which is acquired by moving the hand 12 in the vertical direction relative to the target member 20. Specifically, the control unit 13 moves the hand 12 in the vertical direction relative to the target member 20 from a state in which the detection unit 14 detects the outer circumferential edge portion 20b of the target member 20 until a state in which the detection unit 14 does not detect the outer circumferential edge portion 20b of the target member 20. Then, the control unit 13 acquires the position 20c of the target member 20 in the vertical direction based on the position of the hand 12 in the vertical direction at the timing at which the detection unit 14 switches between a state in which the outer circumferential edge portion 20b of the target member 20 is detected and a state in which the detection unit 14 does not detect the outer circumferential edge portion 20b of the target member 20.

Then, the control unit 13 corrects the placement position PP of the substrate W in the vertical direction based on the acquired position 20c of the target member 20 in the vertical direction and the previously acquired relative positional relationship in the vertical direction between the position 20c of the target member 20 and the placement site 200 for the substrate W. Note that the control unit 13 acquires the relative positional relationship in the vertical direction between the position 20c of the target member 20 and the placement site 200 for the substrate W in advance before correcting the placement position PP of the substrate W in the vertical direction.

(Acquisition of the inclination of the coordinate system of the substrate placement location relative to the coordinate system of the robot arm in the horizontal plane)
7, the coordinate system C2 of the substrate W placement site 200 may be inclined relative to the coordinate system C1 of the robot arm 11 in the horizontal plane. In this case, the accuracy of correcting the placement position PP of the substrate W in the horizontal plane decreases. Therefore, when correcting the placement position PP of the substrate W in the horizontal plane, it is preferable for the substrate transport robot 10 to recognize the inclination α of the coordinate system C2 of the substrate W placement site 200 relative to the coordinate system C1 of the robot arm 11 in the horizontal plane. Therefore, before correcting the placement position PP of the substrate W in the horizontal plane, the substrate transport robot 10 acquires the inclination α of the coordinate system C2 of the substrate W placement site 200 relative to the coordinate system C1 of the robot arm 11 in the horizontal plane as follows.

The substrate transport robot system 100 includes a target member 21. Similar to the target member 20, the target member 21 is a member for correcting the placement position PP of the substrate W in the horizontal plane and in the vertical direction by the substrate transport robot 10. The target member 21 is disposed at a different position from the target member 20 in the horizontal plane. Specifically, the target member 21 is disposed on the opposite side of the target member 20. The target member 21 is also disposed in the horizontal plane such that the straight line connecting the center position 20a of the target member 20 and the center position 21a of the target member 21 is parallel to the X direction of the coordinate system C2 of the substrate W placement site 200. The target member 21 is an example of a second horizontal target member and a vertical target member.

Then, the control unit 13 obtains the center position 20a of the target member 20 in the horizontal plane and the center position 21a of the target member 21 in the horizontal plane using the method described above.

Then, the control unit 13 acquires the tilt α of the coordinate system C2 of the substrate W placement site 200 relative to the coordinate system C1 of the robot arm 11 in the horizontal plane based on the center position 20a of the target member 20 in the horizontal plane, the center position 21a of the target member 21 in the horizontal plane, and the previously acquired relative positional relationship in the horizontal plane between the center position 20a of the target member 20 and the center position 21a of the target member 21. Specifically, the control unit 13 acquires the angle in the X direction of the coordinate system C2 of the substrate W placement site 200 relative to the X direction of the coordinate system C1 of the robot arm 11 in the horizontal plane as the tilt α of the coordinate system C2 of the substrate W placement site 200 relative to the coordinate system C1 of the robot arm 11. The control unit 13 acquires the relative positional relationship in the horizontal plane between the center position 20a of the target member 20 and the center position 21a of the target member 21 before correcting the placement position PP of the substrate W in the horizontal direction.

(The robot arm's coordinate system is calibrated so that the direction in which the hand approaches the target part is perpendicular to the direction of the detection light.)

As shown in FIG. 8, when the detection unit 14 is attached to the hand 12 so as to be shifted from the design position, the direction in which the hand 12 approaches the target member 20 and the direction of the detection light DL may not be orthogonal. In this case, the accuracy of correcting the placement position PP of the substrate W in the horizontal plane decreases. Therefore, when correcting the placement position PP of the substrate W in the horizontal plane, it is preferable for the substrate transport robot 10 to make the direction in which the hand 12 approaches the target member 20 and the direction of the detection light DL orthogonal. Therefore, before correcting the placement position PP of the substrate W in the horizontal plane, the substrate transport robot 10 calibrates the coordinate system C1 of the robot arm 11 as follows so that the direction in which the hand 12 approaches the target member 20 and the direction of the detection light DL are orthogonal to each other.

First, as shown in FIG. 9, the control unit 13 obtains the direction of the detection light DL with respect to the hand 12 based on the multiple positions of the hand 12 where the detection light DL is blocked by bringing the hand 12 closer to the target member 20 while changing the position where the detection light DL is blocked. Specifically, the control unit 13 brings the hand 12 closer to the target member 20 and obtains a first position P1 of the hand 12 where the detection light DL is blocked. Then, the control unit 13 brings the hand 12 closer to the target member 20 while moving it in the X direction and obtains a second position P2 of the hand 12 where the detection light DL is blocked and different from the first position P1. Then, the control unit 13 obtains the direction of the straight line connecting the first position P1 and the second position P2 of the hand 12 with respect to the X direction of the coordinate system C1 of the robot arm 11 as the inclination β of the detection light DL with respect to the direction perpendicular to the approaching direction of the hand 12. Note that, in order to obtain the direction of the detection light DL with respect to the hand 12, three or more positions where the detection light DL is blocked may be obtained.

10, the control unit 13 calibrates the coordinate system C1 of the robot arm 11 based on the acquired direction of the detection light DL so that the direction in which the hand 12 approaches the target member 20 is perpendicular to the direction of the detection light DL. Specifically, the control unit 13 converts the coordinate system C1 of the robot arm 11 (see FIG. 8), in which the direction in which the hand 12 approaches the target member 20 and the direction of the detection light DL are not perpendicular to each other, into the coordinate system C3 of the robot arm 11 in which the direction in which the hand 12 approaches the target member 20 and the direction of the detection light DL are perpendicular to each other, based on the inclination β of the detection light DL with respect to the direction perpendicular to the direction in which the hand 12 approaches.

[Method for correcting substrate placement position by substrate transport robot]
11, a method for correcting the placement position PP of the substrate W by the substrate transport robot 10 will be described. Note that in the following description of the method for correcting the placement position PP of the substrate W, only the correction of the placement position PP of the substrate W in the horizontal plane will be described among the corrections of the placement position PP of the substrate W by the substrate transport robot 10.

First, as shown in FIG. 11, in step S1, the hand 12 approaches the target member 20 from a first direction in a horizontal plane, and the detection unit 14 is used to obtain a first tangent line TL1 corresponding to the outer peripheral edge portion 20b of the target member 20.

Next, in step S2, the hand 12 is brought closer to the target member 20 from a second direction in the horizontal plane different from the first direction, and the detection unit 14 is used to obtain a second tangent line TL2 corresponding to the outer peripheral edge portion 20b of the target member 20.

Next, in step S3, the center position 20a of the target member 20 is obtained based on the obtained first tangent line TL1 and the obtained second tangent line TL2.

Next, in step S4, the placement position PP of the substrate W in the horizontal plane is corrected based on the acquired central position 20a of the target member 20 in the horizontal plane and the previously acquired relative positional relationship in the horizontal plane between the central position 20a of the target member 20 and the placement site 200 for the substrate W.

[Effects of the embodiment]
In this embodiment, the following effects can be obtained.

(Effects of the substrate transport robot system)
In this embodiment, the control unit 13 obtains the center position 20a of the target member 20 in the horizontal plane based on a first tangent TL1 corresponding to the outer peripheral edge 20b of the target member 20 obtained by using the detection unit 14 when the hand 12 approaches the target member 20 from a first direction in the horizontal plane, and a second tangent TL2 corresponding to the outer peripheral edge 20b of the target member 20 obtained by using the detection unit 14 when the hand 12 approaches the target member 20 from a second direction in the horizontal plane different from the first direction. As a result, if the first tangent TL1 and the second tangent TL2 are obtained once each, the center position 20a of the target member 20 can be obtained immediately based on the first tangent TL1 and the second tangent TL2. In other words, the center position 20a of the target member 20 in the horizontal plane can be obtained quickly compared to a case in which the hand 12 is swung, the offset amount of the hand 12 is calculated, the position of the hand 12 is shifted, and the like are repeatedly performed to specify the center position 20a of the target member 20 in the horizontal plane. This allows the placement position PP of the substrate W in the horizontal plane to be quickly corrected, thereby shortening the time required to correct the placement position PP of the substrate W in the horizontal plane.

In addition, in this embodiment, the detection unit 14 detects the position 20c of the target member 20 for correcting the placement position PP of the substrate W in the vertical direction. The control unit 13 then obtains the position 20c of the target member 20 in the vertical direction based on the timing at which the detection unit 14 switches between a state in which the target member 20 is detected in the vertical direction and a state in which it is not detected in the vertical direction, which is obtained by moving the hand 12 in the vertical direction relative to the target member 20. The control unit 13 also corrects the placement position PP of the substrate W in the vertical direction based on the obtained position 20c of the target member 20 in the vertical direction and the relative positional relationship in the vertical direction between the position 20c of the target member 20 and the placement site 200 of the substrate W, which has been obtained in advance. This allows correction of the placement position PP of the substrate W in the vertical direction in addition to correction of the placement position PP of the substrate W in the horizontal plane.

Furthermore, in this embodiment, the target member 20 is a member for correcting the placement position PP of the substrate W in the horizontal plane and in the vertical direction. This allows the correction of the placement position PP of the substrate W in the horizontal plane and the placement position PP of the substrate W in the vertical direction to be performed using a common target member 20. This allows the configuration to be simplified without adding a member for correcting the placement position PP of the substrate W in the vertical direction, even when correcting the placement position PP of the substrate W in the horizontal plane as well as the placement position PP of the substrate W in the vertical direction.

In addition, in this embodiment, the substrate transport robot system 100 includes, in addition to the target member 20, a target member 21 arranged at a position different from the target member 20 in the horizontal plane. The control unit 13 acquires the inclination α of the coordinate system C2 of the substrate W storage site 200 relative to the coordinate system C1 of the robot arm 11 in the horizontal plane based on the center position 20a of the target member 20 in the horizontal plane, the center position 21a of the target member 21 in the horizontal plane, and the relative positional relationship in the horizontal plane between the center position 20a of the target member 20 and the center position 21a of the target member 21 that has been acquired in advance. This allows the substrate transport robot 10 to recognize the inclination α of the coordinate system C2 of the substrate W storage site 200 relative to the coordinate system C1 of the robot arm 11 in the horizontal plane even if the coordinate system C2 of the substrate W storage site 200 is inclined relative to the coordinate system C1 of the robot arm 11 in the horizontal plane. This makes it possible to prevent a decrease in the accuracy of correcting the placement position PP of the substrate W in the horizontal plane due to the inclination of the coordinate system C2 of the substrate W placement site 200 relative to the coordinate system C1 of the robot arm 11 in the horizontal plane. Note that the center position 20a of the target member 20 in the horizontal plane and the center position 21a of the target member 21 in the horizontal plane can be obtained more quickly than when the hand 12 is swung, the offset amount of the hand 12 is calculated, the position of the hand 12 is shifted, and so on, as described above. That is, even if the inclination α of the coordinate system C2 of the substrate W placement site 200 relative to the coordinate system C1 of the robot arm 11 in the horizontal plane is obtained, the time required to correct the placement position PP of the substrate W in the horizontal plane can be shortened.

In this embodiment, the hand 12 includes a first tip 12a and a second tip 12b that are bifurcated. The detection unit 14 is a transmission sensor that detects the target member 20 based on whether the detection light DL passing through the space S between the first tip 12a and the second tip 12b is blocked. The control unit 13 then approaches the hand 12 to the target member 20 while changing the position where the detection light DL is blocked, and acquires the direction of the detection light DL relative to the hand 12 based on the multiple positions of the hand 12 where the detection light DL is blocked. Based on the acquired direction of the detection light DL, the control unit 13 calibrates the coordinate system C1 of the robot arm 11 so that the direction in which the hand 12 approaches the target member 20 and the direction of the detection light DL are orthogonal. This makes it easy to make the direction in which the hand 12 approaches the target member 20 and the direction of the detection light DL orthogonal, even if the direction in which the hand 12 approaches the target member 20 and the direction of the detection light DL are not orthogonal. This makes it possible to prevent a decrease in the accuracy of correcting the placement position PP of the substrate W in the horizontal plane caused by the direction in which the hand 12 approaches the target member 20 not being perpendicular to the direction of the detection light DL.

(Effect of the method for correcting the placement position of the substrate by the substrate transport robot)
In this embodiment, the hand 12 is brought close to the target member 20 from a first direction in a horizontal plane, and the first tangent TL1 of the outer periphery 20b of the target member 20 is obtained using the detection unit 14. The hand 12 is brought close to the target member 20 from a second direction in the horizontal plane different from the first direction, and the second tangent TL2 of the outer periphery 20b of the target member 20 is obtained using the detection unit 14. The center position 20a of the target member 20 is obtained based on the obtained first tangent TL1 and the obtained second tangent TL2. As a result, similar to the substrate transport robot system 100, once the first tangent TL1 and the second tangent TL2 are obtained, the center position 20a of the target member 20 can be obtained immediately based on the first tangent TL1 and the second tangent TL2. As a result, similar to the substrate transport robot system 100, the time required to correct the placement position PP of the substrate W in the horizontal plane can be shortened.

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

For example, in the above embodiment, an example was shown in which the control unit 13 calibrates the coordinate system C1 of the robot arm 11 based on the acquired direction of the detection light DL so that the direction in which the hand 12 approaches the target member 20 is perpendicular to the direction of the detection light DL, but the present disclosure is not limited to this. In the present disclosure, the control unit does not need to calibrate the coordinate system of the robot arm based on the acquired direction of the detection light so that the direction in which the hand approaches the target member is perpendicular to the direction of the detection light. In that case, it is preferable that the detection unit is disposed with respect to the hand so that the direction in which the hand approaches the target member is perpendicular to the direction of the detection light.

In addition, in the above embodiment, an example was shown in which the detection unit 14 is a transmission type sensor that detects the target member 20 based on whether or not the detection light DL passing through the space S between the first tip 12a and the second tip 12b is blocked, but the present disclosure is not limited to this. In the present disclosure, the detection unit may be a reflective sensor. Also, the detection unit may be a sensor that does not use detection light. In that case, the hand does not need to be bifurcated.

In the above embodiment, the control unit 13 acquires the tilt α of the coordinate system C2 of the substrate W placement site 200 relative to the coordinate system C1 of the robot arm 11 in the horizontal plane based on the center position 20a of the target member 20 in the horizontal plane, the center position 21a of the target member 21 in the horizontal plane, and the relative positional relationship in the horizontal plane between the center position 20a of the target member 20 and the center position 21a of the target member 21 that has been acquired in advance, but the present disclosure is not limited to this. In the present disclosure, the control unit may acquire the tilt of the coordinate system of the substrate placement site relative to the coordinate system of the robot arm in the horizontal plane by a method other than the above method. Also, the control unit does not need to acquire the tilt of the coordinate system of the substrate placement site relative to the coordinate system of the robot arm in the horizontal plane. In that case, it is preferable that the robot arm and the substrate placement site are arranged so that the coordinate system of the substrate placement site is not tilted relative to the coordinate system of the robot arm in the horizontal plane.

In the above embodiment, an example was shown in which the substrate transport robot system 100 includes, in addition to the target member 20, a target member 21 that is positioned in a different position from the target member 20 in the horizontal plane, but the present disclosure is not limited to this. In the present disclosure, the substrate transport robot system may include only one target member.

In addition, in the above embodiment, an example was shown in which the target member 20 is a member for correcting the placement position PP of the substrate W in the horizontal plane and in the vertical direction, but the present disclosure is not limited to this. In the present disclosure, the target member for correcting the placement position of the substrate in the horizontal plane and the target member for correcting the placement position of the substrate in the vertical direction may be separate members.

In addition, in the above embodiment, an example has been shown in which the substrate transport robot 10 corrects the placement position PP of the substrate W in the horizontal plane as well as the placement position PP of the substrate W in the vertical direction, but the present disclosure is not limited to this. In the present disclosure, the substrate transport robot may only correct the placement position of the substrate in the horizontal plane without correcting the placement position of the substrate in the vertical direction.

In the above embodiment, an example was shown in which the control unit 13, which is provided in the substrate transport robot 10 and controls the operation of the robot arm 11, acquires the center position 20a of the target member 20 in the horizontal plane and corrects the placement position PP of the substrate W in the horizontal plane, but the present disclosure is not limited to this. In the present disclosure, the control unit that controls the operation of the robot arm and the control unit that acquires the center position of the target member in the horizontal plane and corrects the acquired center position of the target member in the horizontal plane and the placement position of the substrate in the horizontal plane may be separate control units. Furthermore, the substrate transport robot does not need to be provided with a control unit that acquires the center position of the target member in the horizontal plane and corrects the acquired center position of the target member in the horizontal plane and the placement position of the substrate in the horizontal plane.

In addition, in the above embodiment, an example was shown in which the placement position PP of the substrate W was corrected, but the present disclosure is not limited to this. In the present disclosure, instead of the placement position of the substrate, the take-up position of the substrate may be corrected, or both the placement position and take-up position of the substrate may be corrected. When the take-up position of the substrate is corrected, the target member is a member for making a correction to match the take-up position of the substrate with the placement location of the substrate.

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. Processors are considered processing circuits or circuits because they include transistors and other circuits. 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 the processor.

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

(Item 1)
a substrate transport robot that transports the substrate;
a horizontal target member having a circular shape when viewed from above and below, for correcting at least one of a placement position and a removal position of the substrate in a horizontal plane;
A control unit,
The substrate transport robot includes:
A robot arm;
A hand attached to the tip of the robot arm;
a detection unit disposed in the hand and detecting an outer periphery of the horizontal target member;
The control unit is
a center position of the horizontal target member in a horizontal plane is obtained based on a first tangent corresponding to the outer periphery of the horizontal target member obtained using the detection unit by bringing the hand closer to the horizontal target member from a first direction in a horizontal plane, and a second tangent corresponding to the outer periphery of the horizontal target member obtained using the detection unit by bringing the hand closer to the horizontal target member from a second direction in the horizontal plane different from the first direction;
A substrate transport robot system which corrects at least one of the placement position and the removal position of the substrate in a horizontal plane based on the acquired central position of the horizontal target member in the horizontal plane and a previously acquired relative positional relationship in the horizontal plane between the central position of the horizontal target member and the substrate placement location.

(Item 2)
Further, a vertical target member is provided for correcting at least one of the placement position and the removal position of the substrate in a vertical direction,
The detection unit detects the position of the upper and lower target members,
The control unit is
a position of the vertical target member in the vertical direction is acquired based on a timing at which the detection unit switches between a state in which the vertical target member is detected and a state in which the vertical target member is not detected in the vertical direction, the timing being acquired by moving the hand in the vertical direction relative to the vertical target member; and
2. A substrate transport robot system as described in item 1, which corrects at least one of the placement position and the removal position of the substrate in the vertical direction based on the acquired position of the upper and lower target members in the vertical direction and a relative positional relationship in the vertical direction between the position of the upper and lower target members and the placement location of the substrate that has been acquired in advance.

(Item 3)
3. The substrate transport robot system according to claim 2, wherein the upper and lower target members are the same target member as the horizontal target member.

(Item 4)
the horizontal target members include a first horizontal target member and a second horizontal target member disposed at a position different from that of the first horizontal target member in a horizontal plane,
The control unit obtains the inclination of the coordinate system of the substrate placement location relative to the coordinate system of the robot arm in the horizontal plane based on the central position of the first horizontal target member in the horizontal plane, the central position of the second horizontal target member in the horizontal plane, and a previously obtained relative positional relationship in the horizontal plane between the central position of the first horizontal target member and the central position of the second horizontal target member. A substrate transport robot system as described in any one of items 1 to 3.

(Item 5)
The hand includes a first tip portion and a second tip portion that are bifurcated into two parts,
the detection unit is a transmission sensor that detects the horizontal target member based on whether detection light passing through a space between the first tip portion and the second tip portion is blocked,
The control unit is
The hand is moved closer to the horizontal target member while changing the position where the detection light is blocked, and the direction of the detection light with respect to the hand is acquired based on a plurality of positions of the hand where the detection light is blocked; and
5. The substrate transport robot system according to claim 1, further comprising: a coordinate system of the robot arm that is calibrated based on the acquired direction of the detection light so that the direction in which the hand approaches the horizontal target member is perpendicular to the direction of the detection light.

(Item 6)
A method for correcting at least one of a placement position and a pick-up position of a substrate by a substrate transport robot, the substrate transport robot comprising: a robot arm; a hand attached to a tip of the robot arm; and a detection unit having a circular shape when viewed from above and below, the detection unit detecting a horizontal target member for correcting at least one of a placement position and a pick-up position of a substrate in a horizontal plane, the method comprising:
Bringing the hand close to the horizontal target member from a first direction in a horizontal plane, and acquiring a first tangent corresponding to an outer periphery of the horizontal target member using the detection unit;
bringing the hand close to the horizontal target member from a second direction in a horizontal plane different from the first direction, and acquiring a second tangent corresponding to the outer periphery of the horizontal target member using the detection unit;
Obtaining a center position of the horizontal target member based on the obtained first tangent line and the obtained second tangent line;
and correcting at least one of the placement position and the pick-up position of the substrate by a substrate transport robot, the method comprising: correcting at least one of the placement position and the pick-up position of the substrate in a horizontal plane based on the acquired central position and a relative positional relationship in the horizontal plane between the central position and a placement location of the substrate that has been acquired in advance.

Claims

a substrate transport robot that transports the substrate;
a horizontal target member having a circular shape when viewed from above and below, for correcting at least one of a placement position and a removal position of the substrate in a horizontal plane;
A control unit,
The substrate transport robot includes:
A robot arm;
A hand attached to the tip of the robot arm;
a detection unit disposed in the hand and detecting an outer periphery of the horizontal target member;
The control unit is
a center position of the horizontal target member in a horizontal plane is obtained based on a first tangent corresponding to the outer periphery of the horizontal target member obtained using the detection unit by bringing the hand closer to the horizontal target member from a first direction in a horizontal plane, and a second tangent corresponding to the outer periphery of the horizontal target member obtained using the detection unit by bringing the hand closer to the horizontal target member from a second direction in the horizontal plane different from the first direction;
A substrate transport robot system which corrects at least one of the placement position and the removal position of the substrate in a horizontal plane based on the acquired central position of the horizontal target member in the horizontal plane and a previously acquired relative positional relationship in the horizontal plane between the central position of the horizontal target member and the substrate placement location.
Further, a vertical target member is provided for correcting at least one of the placement position and the removal position of the substrate in a vertical direction,
The detection unit detects the position of the upper and lower target members,
The control unit is
a position of the vertical target member in the vertical direction is acquired based on a timing at which the detection unit switches between a state in which the vertical target member is detected and a state in which the vertical target member is not detected in the vertical direction, the timing being acquired by moving the hand in the vertical direction relative to the vertical target member; and
2. The substrate transport robot system of claim 1, wherein at least one of the placement position and the removal position of the substrate in the vertical direction is corrected based on the acquired position of the upper and lower target members in the vertical direction and a previously acquired relative positional relationship in the vertical direction between the position of the upper and lower target members and the placement location of the substrate.
The substrate transport robot system of claim 2, wherein the vertical target members are the same target members as the horizontal target members.
the horizontal target members include a first horizontal target member and a second horizontal target member disposed at a position different from that of the first horizontal target member in a horizontal plane,
2. The substrate transport robot system of claim 1, wherein the control unit acquires an inclination of the coordinate system of the substrate placement location relative to the coordinate system of the robot arm in a horizontal plane based on the central position of the first horizontal target member in a horizontal plane, the central position of the second horizontal target member in a horizontal plane, and a previously acquired relative positional relationship in the horizontal plane between the central position of the first horizontal target member and the central position of the second horizontal target member.
The hand includes a first tip portion and a second tip portion that are bifurcated into two parts,
the detection unit is a transmission sensor that detects the horizontal target member based on whether detection light passing through a space between the first tip portion and the second tip portion is blocked,
The control unit is
The hand is moved closer to the horizontal target member while changing the position where the detection light is blocked, and the direction of the detection light with respect to the hand is acquired based on a plurality of positions of the hand where the detection light is blocked; and
2. The substrate transport robot system according to claim 1, further comprising: a coordinate system of the robot arm that is calibrated based on the acquired direction of the detection light so that the direction in which the hand approaches the horizontal target member is perpendicular to the direction of the detection light.
A method for correcting at least one of a placement position and a pick-up position of a substrate by a substrate transport robot, the substrate transport robot comprising: a robot arm; a hand attached to a tip of the robot arm; and a detection unit having a circular shape when viewed from above and below, the detection unit detecting a horizontal target member for correcting at least one of a placement position and a pick-up position of a substrate in a horizontal plane, the method comprising:
Bringing the hand close to the horizontal target member from a first direction in a horizontal plane, and acquiring a first tangent corresponding to an outer periphery of the horizontal target member using the detection unit;
bringing the hand close to the horizontal target member from a second direction in a horizontal plane different from the first direction, and acquiring a second tangent corresponding to the outer periphery of the horizontal target member using the detection unit;
Obtaining a center position of the horizontal target member based on the obtained first tangent line and the obtained second tangent line;
and correcting at least one of the placement position and the pick-up position of the substrate by a substrate transport robot, the method comprising: correcting at least one of the placement position and the pick-up position of the substrate in a horizontal plane based on the acquired central position and a relative positional relationship in the horizontal plane between the central position and a placement location of the substrate that has been acquired in advance.