Control method and substrate conveying system

Abstract

The present invention provides a control method for a substrate transport system and a substrate transport system capable of improving transport accuracy. The control method of the present invention is a control method for a transport mechanism having a holding portion for holding a substrate and capable of transporting the substrate, comprising the steps of detecting the outer edge of the substrate being transported by the transport mechanism and measuring the center position of the substrate using a preset adjustment value corresponding to a path for transporting the substrate; correcting a target position based on an offset between the center position of the substrate and a preset reference position of the holding portion; and controlling the transport mechanism so that the reference position of the holding portion becomes the corrected target position.

Description

Technical Field

[0001] The present invention relates to a control method and a substrate conveying system. Background Art

[0002] There is known a substrate transport system including a transport mechanism for transporting substrates such as wafers.

[0003] Patent document 1 discloses a position offset detection device for a workpiece disposed on a conveying mechanism, wherein the conveying mechanism rotatably connects a plurality of arms in series, and causes the frontmost arm to hold the workpiece to convey the workpiece. The position offset detection device includes: an edge detection mechanism disposed on an arm other than the frontmost arm among the plurality of arms, for detecting an edge of the workpiece held at least by the frontmost arm; and a position offset detection unit for obtaining the position offset of the workpiece based on a detection value of the edge detection mechanism.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent Application Laid-Open No. 2008-311303 Summary of the Invention

[0007] Technical problem to be solved by the invention

[0008] However, the conveying mechanism is required to convey the material to the target position with high precision.

[0009] One embodiment of the present invention provides a control method and a substrate transport system capable of improving transport accuracy.

[0010] Technical solutions to technical problems

[0011] A control method according to one embodiment of the present invention is a control method for a conveying mechanism having a holding portion for holding a substrate and capable of conveying the substrate, the method comprising: a step of detecting the outer edge of the substrate conveyed by the conveying mechanism and measuring the center position of the substrate using a predetermined adjustment value corresponding to a path for conveying the substrate; a step of correcting a target position based on an offset between the center position of the substrate and a predetermined reference position of the holding portion; and a step of controlling the conveying mechanism so that the reference position of the holding portion becomes the corrected target position.

[0012] Effects of the Invention

[0013] According to one embodiment of the present invention, a control method and a substrate transport system capable of improving transport accuracy are provided. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 This is an example of a plan view showing the structure of a substrate processing system according to one embodiment.

[0015] Figure 2 This is an example of a functional block diagram of a control device.

[0016] Figure 3 This is a diagram illustrating an example of the operation of the transport mechanism when transporting a substrate from one placement section to another.

[0017] Figure 4 This is a diagram for explaining an example of the operation of the transport mechanism when transporting a substrate from one placement section to another.

[0018] Figure 5 This is an example of a diagram illustrating a route when transporting from a measurement position to a target position.

[0019] Figure 6 This is an example of a diagram showing the relationship between the shape of the third arm holding the substrate and the sensor.

[0020] Figure 7 This is an example of a diagram illustrating a path when transporting from a measurement position to a target position.

[0021] Figure 8 This is an example of a diagram illustrating a path when transporting from a measurement position to a target position.

[0022] Figure 9 This is an example of a diagram illustrating a path when transporting from a measurement position to a target position.

[0023] Description of Reference Numerals

[0024] W substrate

[0025] 1. Substrate processing system

[0026] 2 Load lock chamber

[0027] 21 Loading section

[0028] 3 Vacuum conveying chamber

[0029] 4 Processing Chamber

[0030] 41 Loading section

[0031] 5 Conveying mechanism

[0032] 53 Arm 3

[0033] 53a Holding portion

[0034] 6, 6a, 6b, 61, 62 Sensors (measuring unit)

[0035] 7 Control device

[0036] 71 Attitude Calculation Unit

[0037] 72 Center position calculation unit

[0038] 73 Storage

[0039] 91~93 motor

[0040] 91a~93a Angle sensor. DETAILED DESCRIPTION

[0041] Hereinafter, the embodiment of the present invention will be described with reference to the accompanying drawings. In each of the drawings, the same components are denoted by the same reference numerals, and overlapping descriptions may be omitted.

[0042] <Substrate processing system>

[0043] use Figure 1 An example of the overall configuration of the substrate processing system 1 according to one embodiment will be described. Figure 1 1 is an example of a top view showing the structure of a substrate processing system 1 according to an embodiment. Figure 1 , the substrate W is illustrated with dotted hatching. In the following description, a case where the substrate W is held by the third arm 53 of the transport mechanism 5 and transported from the vacuum transport chamber 3 to the placement portion 41 of the processing chamber 4 will be described.

[0044] Figure 1 The substrate processing system 1 shown is a clustered (multi-chamber) system. It includes a load lock chamber 2, a vacuum transfer chamber 3, a processing chamber 4, a transfer mechanism 5, a sensor 6, and a control device 7. Furthermore, a substrate transport system for transporting substrates W includes the transfer mechanism 5, the sensor 6, and the control device 7.

[0045] The load lock chamber 2 is disposed between the vacuum transfer chamber 3 and the atmospheric transfer chamber (not shown). The load lock chamber 2 includes a loading portion 21 for loading a substrate W. The load lock chamber 2 is configured to be switchable between an atmospheric atmosphere and a vacuum atmosphere. The load lock chamber 2 communicates with the vacuum transfer chamber 3, which has a vacuum atmosphere, by opening and closing a gate valve 22. The load lock chamber 2 communicates with the atmospheric transfer chamber (not shown) with an atmospheric atmosphere by opening and closing a gate valve (not shown). The switching between the vacuum atmosphere and the atmospheric atmosphere within the load lock chamber 2 is controlled by a control device 7.

[0046] The vacuum transfer chamber 3 is decompressed to a predetermined vacuum atmosphere. A transfer mechanism 5 for transferring the substrate W is provided inside the vacuum transfer chamber 3 .

[0047] The processing chamber 4 is arranged adjacent to the vacuum transfer chamber 3. The processing chamber 4 includes a loading portion 41 for loading a substrate W. The processing chamber 4 is decompressed to a predetermined vacuum atmosphere, and a desired process (e.g., etching, film formation, cleaning, ashing, etc.) is performed on the substrate W loaded on the loading portion 41. The processing chamber 4 and the vacuum transfer chamber 3 are connected by opening and closing a gate 42. Furthermore, the operation of each component used for processing in the processing chamber 4 is controlled by a control device 7.

[0048] The transport mechanism 5 transfers substrates W between the load lock chamber 2 and the vacuum transfer chamber 3 in response to the opening and closing of the gate 22. Furthermore, the transport mechanism 5 transfers substrates W between the processing chamber 4 and the vacuum transfer chamber 3 in response to the opening and closing of the gate 42. The operation of the transport mechanism 5 and the opening and closing of the gates 22 and 42 are controlled by the control device 7.

[0049] The transport mechanism 5 is configured as a multi-jointed arm having, for example, a base 50, a first arm 51, a second arm 52, and a third arm 53. The base 50 is rotatably connected to one longitudinal side of the first arm 51 by a rotation shaft 55. The other longitudinal side of the first arm 51 is rotatably connected to one longitudinal side of the second arm 52 by a rotation shaft 56. The other longitudinal side of the second arm 52 is rotatably connected to one longitudinal side of the third arm 53 by a rotation shaft 57. The other longitudinal side of the third arm 53 has a holding portion 53a for holding (mounting) the substrate W.

[0050] Inside the vacuum transfer chamber 3, sensors (measuring units) 6 are provided corresponding to the processing chamber 4 and the load lock chamber 2 to detect substrates W transported by the transport mechanism 5. The sensors 6 are provided at positions where substrates W pass when the transport mechanism 5 transports substrates W from the vacuum transfer chamber 3 into the processing chamber 4 or the load lock chamber 2, or when the transport mechanism 5 transports substrates W from the processing chamber 4 or the load lock chamber 2 into the vacuum transfer chamber 3.

[0051] The sensor 6 includes two sensors 6a and 6b. The sensors 6a and 6b are, for example, photoelectric sensors. The substrate W transported by the transport mechanism 5 passes through the sensors 6a and 6b, thereby being able to detect four points on the outer edge of the substrate W. The control device 7 (center position calculation unit 72, described later) detects the outer edge coordinates of the substrate W held by the third arm 53 based on the detection of the outer edge of the substrate W by the sensors 6 (sensors 6a and 6b) and the movement of the transport mechanism 5 at that time. The control device 7 then calculates the center position of the substrate W based on the outer edge coordinates of the detected four points. Thus, the sensor 6 and the control device 7 function as a measuring unit that measures the center position of the substrate W held by the third arm 53. Thus, the control device 7 detects the offset (eccentricity) between the predetermined reference position of the third arm 53 for placing the substrate W (the center position of the holding portion 53a) and the center position of the substrate W held by the third arm 53 detected by the sensor 6.

[0052] The control device 7 includes a CPU (Central Processing Unit), ROM (Read Only Memory), RAM (Random Access Memory), and an HDD (Hard Disk Drive). The control device 7 is not limited to an HDD and may also include other storage areas such as an SSD (Solid State Drive). The HDD, RAM, and other storage areas store recipes that define process flows, process conditions, and transport conditions.

[0053] The CPU controls the processing of substrates W in each processing chamber and the transport of substrates W according to a plan. A program for executing the processing of substrates W in each processing chamber and the transport of substrates W may also be stored in the HDD or RAM. The program may be provided by being stored in a storage medium or provided from an external device via a network.

[0054] <Conveying mechanism>

[0055] Next, use Figure 2 , the control of the conveying mechanism 5 is explained. Figure 2 This is an example of a functional block diagram of the control device 7.

[0056] The detection signal of the sensor 6 is input to the control device 7 .

[0057] The conveying mechanism 5 includes a first-axis motor 91, a second-axis motor 92, and a third-axis motor 93. The first-axis motor 91 is disposed within the first arm 51. The first-axis motor 91 rotates the first arm 51 relative to the base 50 using the rotating shaft 55. The second-axis motor 92 is disposed within the first arm 51. The second-axis motor 92 rotates the second arm 52 relative to the first arm 51 using the rotating shaft 56. The third-axis motor 93 is disposed within the second arm 52. The third-axis motor 93 rotates the third arm 53 relative to the second arm 52 using the rotating shaft 57.

[0058] The conveying mechanism 5 includes a first-axis angle sensor 91a, a second-axis angle sensor 92a, and a third-axis angle sensor 93a. The first-axis angle sensor 91a detects the rotation angle of the first-axis motor 91. The second-axis angle sensor 92a detects the rotation angle of the second-axis motor 92. The third-axis angle sensor 93a detects the rotation angle of the third-axis motor 93. Encoders can be used for the first-axis angle sensor 91a, the second-axis angle sensor 92a, and the third-axis angle sensor 93a, for example. The detection values ​​of the first-axis angle sensor 91a, the second-axis angle sensor 92a, and the third-axis angle sensor 93a are input to the control device 7.

[0059] The control device 7 controls the first-axis motor 91 , the second-axis motor 92 , and the third-axis motor 93 based on the detection values ​​of the first-axis angle sensor 91 a , the second-axis angle sensor 92 a , and the third-axis angle sensor 93 a , thereby controlling the operation of the conveying mechanism 5 .

[0060] Furthermore, the control device 7 includes a posture calculation unit 71 , a center position calculation unit 72 , and a storage unit 73 .

[0061] The posture calculation unit 71 calculates the posture of the transport mechanism 5 based on the detection values ​​of the angle sensors 91a to 93a. Based on the calculated posture of the transport mechanism 5, the reference position of the third arm 53 for placing the substrate W (the center position of the holding portion 53a) is calculated.

[0062] The center position calculation unit 72 detects the outer edge coordinates of the substrate W held by the third arm 53 based on the detection of the outer edge of the substrate W by the sensors 6 (sensors 6a, 6b) and the operation of the conveyance mechanism 5 at that time. Then, the control device 7 calculates the center position of the substrate W based on the outer edge coordinates of the four detected points.

[0063] The storage unit 73 stores calibration data (adjustment values) of the sensor 6 .

[0064] Here, calibration of the sensor 6 refers to an operation for acquiring positional information of the sensor 6 relative to the transport mechanism 5. Specifically, the substrate W is passed over the sensor 6 while being held by the holding portion 53 a such that the center position of the holding portion 53 a coincides with the center position of the substrate W. Thus, positional information of the sensor 6 relative to the transport mechanism 5 is acquired as calibration data.

[0065] The center position calculation unit 72 calculates the center position of the substrate W based on the detection of the outer edge of the substrate W by the sensors 6 (sensors 6 a and 6 b ), the reference position calculated by the posture calculation unit 71 , and the calibration data (sensor position) of the sensors 6 .

[0066] In this manner, the center position calculation unit 72 of the control device 7 uses the sensor 6 to measure the center position of the substrate W. The control device 7 then calculates the offset between the center position of the substrate W and the reference position of the third arm 53 (the center position of the holding portion 53a), and corrects the target position. The control device 7 then controls the transport mechanism 5 so that the reference position of the third arm 53 (the center position of the holding portion 53a) reaches the corrected target position. This allows the substrate W to be transported to the target position.

[0067] Next, use Figures 3 to 5 , an example of the operation of the transport mechanism 5 when transporting the substrate W will be described.

[0068] Figure 3 41B is a diagram for explaining an example of the operation of the transport mechanism 5 when the substrate W is transported from the mounting portion 21 to the mounting portion 41B. Figure 3 (a) is an example of a diagram for explaining the operation of the transport mechanism 5 when the substrate W is transported from the mounting portion 21. Figure 3 In (a), the transport mechanism 5 when receiving the substrate W from the placement unit 21 is indicated by a solid line, and the transport mechanism 5 when transporting the substrate W from the load lock chamber 2 is indicated by a dotted line. Figure 3 (b) is an example of a diagram for explaining the operation of the transport mechanism 5 when the substrate W is transported to the placement portion 41B. Figure 3 In (b), the solid line indicates the transport mechanism 5 when the substrate W passes the measurement position P1 of the sensor 6, and the dashed line indicates the transport mechanism 5 when the substrate W is delivered to the target position P2 of the placement unit 41B. The transport mechanism 5 transports the substrate W from the placement unit 21 to the measurement position P1 via the path 101, and then transports the substrate W from the measurement position P1 to the target position P2 via the path 102. The shaking in the path 102 is exaggerated in the illustration.

[0069] Figure 4 41A and 41B are diagrams for explaining an example of the operation of the transport mechanism 5 when the substrate W is transported from the mounting portion 41A to the mounting portion 41B. Figure 4(a) is an example of a diagram for explaining the operation of the transport mechanism 5 when the substrate W is transported from the mounting portion 41A. Figure 4 In (a), the transport mechanism 5 when receiving the substrate W from the placement portion 41A is indicated by a solid line, and the transport mechanism 5 when transporting the substrate W from the processing chamber 4 is indicated by a dotted line. Figure 4 (b) is an example of a diagram for explaining the operation of the transport mechanism 5 when the substrate W is transported to the placement portion 41B. Figure 4 In (b), the solid line indicates the transport mechanism 5 when the substrate W passes the measurement position P1 of the sensor 6, and the dashed line indicates the transport mechanism 5 when the substrate W is transferred to the target position P2 of the placement unit 41B. The transport mechanism 5 transports the substrate W from the placement unit 41A to the measurement position P1 via the path 201, and then transports the substrate W from the measurement position P1 to the target position P2 via the path 202. The shaking of the path 202 is exaggerated in the illustration.

[0070] Figure 5 This is an example of a diagram illustrating a path when transporting from the measurement position P1 to the target position P2. Furthermore, the shaking in the paths 102 and 202 is exaggeratedly illustrated.

[0071] The posture calculation unit 71 of the control device 7 calculates the reference position of the third arm 53 based on the detection values ​​of the angle sensors 91a to 93a. The control device 7 controls the motors 91 to 93 so that the calculated reference position moves along the path (see the dot-dash line) from the measurement position P1 to the target position P2.

[0072] In addition, due to the torque generated between the arms by the rotating shafts 55 to 57 of the transport mechanism 5 in operation, there is an error between the actual paths 102 and 202 and the paths based on the detection values ​​of the angle sensors 91a to 93a (see the dot-dash lines). Figure 5 As shown, when the substrate W is transported from the measurement position P1 to the target position P2, the path 102 when transported from the placement portion 21 (when transported from the right side relative to the transport direction from the measurement position P1 to the target position P2) is different from the path 202 when transported from the placement portion 41A (when transported from the left side relative to the transport direction from the measurement position P1 to the target position P2). This is due to the action of the transport mechanism 5 before the extension and retraction action from the measurement position P1 to the target position P2 ( Figure 3 Path 101, Figure 4 Therefore, the accuracy of calculating the deviation between the center of the substrate W and the reference position using the sensor 6 is reduced.

[0073] The storage unit 73 of the control device 7 stores calibration data for each transport path. Specifically, each transport path is pre-calibrated, and the calibration data is stored for each transport path. The center position calculation unit 72 calculates the center position of the substrate W using the calibration data corresponding to the transport path. This improves the accuracy of the sensor 6 in calculating the offset between the center position of the substrate W and the reference position. Furthermore, it improves the conveyance accuracy of the substrate W when it is transported to the target position.

[0074] Alternatively, the transport paths may be grouped, calibration performed for each transport path group, and calibration data stored for each transport path group. The center position calculation unit 72 calculates the center position of the substrate W using the calibration data corresponding to the transport path group. Alternatively, the data may be used. This reduces the number of calibration operations and the amount of data stored in the storage unit 73.

[0075] Figure 6 1 is an example of a diagram showing the relationship between the shape of the third arm 53 holding the substrate W and the sensor 6. Figure 6 In FIG, the dot-dash lines represent the trajectories along which the sensors 6a and 6b pass.

[0076] exist Figure 6 In the example shown in (a) of FIG. 5 , the sensor 6 a and the sensor 6 b detect four points on the outer edge of the substrate W. The center position calculation unit 72 can calculate the center position of the substrate W in this manner.

[0077] On the other hand, Figure 6 In the example shown in (b), the third arm 53 has a protrusion 54 that protrudes outward from the substrate W. The outer edge of the protrusion 54 is formed into an arc shape centered on the reference position of the third arm 53. The radius of the arc shape of the protrusion 54 is a known value and is pre-stored in the storage unit 73. The sensor 6a detects two points on the outer edge of the protrusion 54. The sensor 6b detects two points on the outer edge of the substrate W.

[0078] The center position calculation unit 72 calculates the center of the arc of the protrusion 54, in other words, the reference position of the third arm 53, based on the two points on the outer edge of the protrusion 54 detected by the sensor 6a and the arc radius of the protrusion 54. In other words, the sensor 6a and the center position calculation unit 72 function as a reference position measurement unit that measures the reference position of the third arm 53.

[0079] Furthermore, the center position calculation unit 72 calculates the center position of the substrate W based on the two points on the outer edge of the substrate W detected by the sensor 6b and the diameter of the substrate W. In other words, the sensor 6b and the center position calculation unit 72 function as a center position measurement unit that measures the center position of the substrate W. Furthermore, a predetermined diameter of the substrate W may be used. Alternatively, the diameter of the substrate W may be measured in a prior step.

[0080] according to Figure 6 In the structure shown in (b), the reference position of the third arm 53 (the center of the arc of the protrusion 54) is detected using the sensor 6a. In addition, the time when the reference position of the third arm 53 is detected using the sensor 6a and the time when the center position of the substrate W is detected using the sensor 6b can be set to be close to each other. Thus, the errors contained in the two data can be made equal. Thus, when calculating the offset between the center position of the substrate W and the reference position of the third arm 53 (the center position of the holding portion 53a), the error is offset by making a difference, and the offset between the center position of the substrate W and the reference position can be obtained with high precision. Thus, the accuracy of calculating the offset between the center position of the substrate W and the reference position using the sensor 6 can be improved. In addition, the conveying accuracy when the substrate W is conveyed to the target position can be improved.

[0081] In addition, the protrusion 54 is not limited to Figure 6 The shape shown in (b). Figure 6 As shown in (c) of FIG. 5 , a notch 54 a may be provided outside the position where the sensor 6 a passes. This can reduce the width of the third arm 53 .

[0082] Next, the temperature change of the conveying mechanism 5 is described. The conveying mechanism 5 has motors 91 to 93 as heat sources inside. In addition, when the substrate W is conveyed to the high-temperature processing chamber 4, heat is input from the processing chamber 4 to the conveying mechanism 5. In addition, when the high-temperature substrate W processed in the processing chamber 4 is conveyed, heat is transferred from the substrate W to the conveying mechanism 5. Therefore, the connecting rod lengths of the first arm 51 and the second arm 52 change due to thermal expansion. In addition, due to thermal expansion of the gears connected to the motors 91 to 93, the angular transmission error of the rotating shafts 55 to 57 changes. Therefore, there is a possibility that an error will occur between the reference position calculated by the posture calculation unit 71 and the actual reference position. Therefore, there is a possibility that the accuracy of calculating the offset between the center of the substrate W and the reference position using the sensor 6 will be reduced.

[0083] Here, calibration data for each temperature is stored in the storage unit 73 of the control device 7. For example, the storage unit 73 stores calibration data at room temperature and calibration data at high temperature.

[0084] Here, the measurement methods of calibration data at room temperature and calibration data at high temperature are described.

[0085] First, at room temperature, the substrate W is placed on the placement section 41 so that the target position coincides with the center position of the substrate W. The transport mechanism 5 receives the substrate W from the placement section 41 and performs an extension and retraction operation, thereby allowing the substrate W held by the holding portion 53a to pass over the sensor 6. This acquires calibration data for the sensor 6 at room temperature. The substrate W is then returned to the placement section 41.

[0086] Next, the transport mechanism 5 is heated. The heating method may be performed by operating the motors 91 to 93. Alternatively, the transport mechanism 5 may be heated by transporting the substrate W to the high-temperature processing chamber 4.

[0087] When the temperature reaches a predetermined level (high temperature), the transport mechanism 5 receives the substrate W from the placement unit 41 and performs an extension and retraction operation, thereby allowing the substrate W held by the holding portion 53a to pass over the sensor 6. This allows calibration data of the sensor 6 at high temperature to be acquired. The substrate W is then returned to the placement unit 41.

[0088] Alternatively, calibration data may be acquired for each of a plurality of temperatures of the transport mechanism 5 .

[0089] Next, the processing when the substrate W is transported by the transport mechanism 5 will be described. During transport, the control device 7 generates reference data based on the temperature of the transport mechanism 5 during transport and the calibration data for each temperature. The reference data is generated by, for example, temporarily approximating the calibration data for each temperature.

[0090] The center position calculation unit 72 calculates the center position using reference data generated based on the temperature of the conveying mechanism 5 as calibration data for the sensor 6 .

[0091] Thus, by using reference data based on the temperature of the transport mechanism 5, the effects of thermally induced elongation of the arms 51 and 52 and angular transmission errors in the transport mechanism 5 can be reduced. Furthermore, the accuracy of calculating the offset between the center position of the substrate W and the reference position using the sensor 6 can be improved. Furthermore, the transport accuracy of the substrate W when transporting it to the target position can be improved.

[0092] In addition, use Figure 7 and Figure 8 Other methods for improving conveying accuracy are described.

[0093] Figure 7This is an example of a diagram illustrating a path when transporting the substrate W from the measurement position P1 to the target position P2. Here, the transport mechanism 5 transports the substrate W to the measurement position P1 via the path 101 and then directly transports it to the target position P2. At this time, the substrate W passes through the path 102.

[0094] On the other hand, when transporting the substrate W to the measurement position P1 via the path 201, the transport mechanism 5 transports the substrate W in the direction opposite to the path 101, as shown by the path 211. The substrate W is then transported to the measurement position P1 along the path 212 along the path 101. The transport mechanism 5 then transports the substrate W from the measurement position P1 to the target position P2. By operating in this manner, the substrate W is transported via the path 102.

[0095] That is, when conveying from the right side relative to the conveying direction from measurement position P1 to target position P2, the conveyance is carried out directly. On the other hand, when conveying from the left side relative to the conveying direction from measurement position P1 to target position P2, the conveyance is first carried out to the right side relative to the conveying direction, and then from the right side relative to the conveying direction. Furthermore, while the description uses the configuration of conveying from the right side as an example, this is not limiting and a configuration of conveying from the left side is also possible.

[0096] In this manner, even if the path 201 of the substrate W before reaching the measurement position P1 differs from the path 101, the paths 211 and 212 along the path 101 allow the movement (paths 101 and 212) of the transport mechanism 5 from the measurement position P1 to the target position P2 to be identical before the extension and retraction movement. Consequently, the substrate W passes through the sensor 6 under the same conditions when being transported from the loading section 21 to the loading section 41B and when being transported from the loading section 41A to the loading section 41B. This improves the accuracy of calculating the offset between the center position of the substrate W and the reference position using the sensor 6, even when using the same calibration data. Furthermore, the transport accuracy of the substrate W when being transported to the target position can be improved.

[0097] Figure 8 is an example of a diagram illustrating a path when transporting from the measurement position P1 to the target position P2. Figure 8 As shown, when the substrate W is transported from the path 201 , it may deviate from the path 201 midway as shown by a path 213 and reach the measurement position P1 along the path 101 .

[0098] That is, when conveying from the right side relative to the conveying direction from measurement position P1 to target position P2, the conveyance is carried out directly. On the other hand, when conveying from the left side relative to the conveying direction from measurement position P1 to target position P2, the conveyance is first carried out to the right side relative to the conveying direction, and then from the right side relative to the conveying direction. Furthermore, while the description uses the configuration of conveying from the right side as an example, this is not limiting and a configuration of conveying from the left side is also possible.

[0099] Therefore, with Figure 7 Similarly to the case shown, the movement (paths 101 and 213) prior to the extension and retraction of the transport mechanism 5 from the measurement position P1 to the target position P2 can be made identical. Consequently, the substrate W passes through the sensor 6 under the same conditions when being transported from the loading section 21 to the loading section 41B and when being transported from the loading section 41A to the loading section 41B. This improves the accuracy of calculating the offset between the center position of the substrate W and the reference position using the sensor 6, even when using the same calibration data. Furthermore, the transport accuracy of the substrate W to the target position can be improved.

[0100] in addition, Figure 7 and Figure 8 The conveying time of the conveying mechanism 5 shown in FIG. Therefore, the control device 7 can also be configured to include a mode prioritizing conveying accuracy and a mode prioritizing conveying time, allowing switching of the operating modes. In the conveying accuracy priority mode, conveying is performed from the same direction to the measurement position P1 (see paths 101, 212, and 213). In the conveying time priority mode, conveying is performed along different paths to the measurement position P1 (see paths 101 and 201). This allows selection of which of conveying accuracy and conveying speed to prioritize.

[0101] In addition, Figure 7 and Figure 8 In the example shown, the case where the transport path is changed when transporting a substrate W from one loading section (21, 41A) to another loading section (41B) is described as an example, but the present invention is not limited to this. When transporting a substrate W to the loading section 41B, the substrate W may be transported via a predetermined loading section 21. For example, when transporting a substrate W from the loading section 41A to the loading section 41B, the transport mechanism 5 may first transport the substrate W from the loading section 41A to the loading section 21, and then transport the substrate W from the loading section 21 to the loading section 41B. Alternatively, when transporting a substrate W from the loading section 21 to the loading section 41B, the transport mechanism 5 may transport the substrate W directly from the loading section 21 to the loading section 41B.

[0102] This allows the same movement (path 101) of the transport mechanism 5 from the measurement position P1 to the target position P2 before the extension and retraction movement. Furthermore, even when using the same calibration data, the accuracy of calculating the offset between the center position of the substrate W and the reference position using the sensor 6 can be improved. Furthermore, the transport accuracy of the substrate W when transporting it to the target position can be improved.

[0103] Figure 9 This is an example of a diagram illustrating a path when conveying from the measurement position P1 to the target position P2. The sensor 6 includes a sensor 61 and a sensor 62.

[0104] Here, the measurement position P1 is a position (an oblique light position of the sensor 61 ) where the outer edge of the substrate W is detected by utilizing the fact that the substrate W blocks the sensor 61 . At this position, the path 101 and the path 201 coincide with each other.

[0105] Position P3 is the position where the outer edge of the substrate W is detected (the light projection position of the sensor 61) by utilizing the fact that the substrate W has passed the sensor 61. At this position, the positions of the paths 102 and 202 are offset. Therefore, when using the same reference data, the measurement accuracy of the deviation between the center position of the substrate W and the reference position decreases due to the different transport paths.

[0106] Position P4 is a position midway between position P3 and target position P2, and is the position where the outer edge of substrate W is detected (the light projection position of sensor 62) by utilizing the fact that substrate W passes through sensor 62. Here, path 102 and path 202 merge before position P4 and go to target position P2.

[0107] Here, the sensor 6 detects the outer edge of the substrate W at a position that does not depend on the movement (path) of the conveying mechanism 5. Figure 9 In the example shown, sensor 6 calculates the center position of substrate W based on the oblique light position of sensor 61 and the light projection position of sensor 62. This allows the motion (paths 101 and 201) of transport mechanism 5 prior to the extension and retraction of transport mechanism 5 from measurement position P1 to target position P2 to differ. Consequently, even if the motion (paths 102 and 202) from measurement position P1 to target position P2 differs, the outer edge of substrate W can be detected at a position independent of the motion. This improves the accuracy of calculating the offset between the center position of substrate W and the reference position using sensor 6, even when using the same calibration data. Furthermore, it improves the accuracy of transporting substrate W to the target position.

[0108] While embodiments of the substrate processing system 1 and the substrate transport system have been described above, the present invention is not limited to the above embodiments and various modifications and improvements are possible within the scope of the gist of the present invention as described in the claims.

Claims

1. A control method, characterized in that: The control method is a control method for a conveying mechanism having a holding portion for holding a substrate and capable of conveying the substrate. The holding portion has a protrusion that protrudes beyond the held substrate. The control method includes: When the substrate is conveyed by the conveying mechanism, the outer edge of the protruding portion is detected by a measuring unit at a measuring position on a conveying path to a target position to measure a reference position of the holding portion, and the outer edge of the substrate is detected by the measuring unit at the measuring position, and the center position of the substrate is measured using an adjustment value preset corresponding to the conveying path of the substrate; a step of correcting the target position based on an amount of deviation between the center position of the substrate and a preset reference position of the holding portion; and The step of controlling the transport mechanism so that the reference position of the holding portion becomes the corrected target position.

2. The control method according to claim 1, wherein: The outer edge of the protrusion has an arc shape centered on a reference position of the holding portion.

3. The control method according to claim 1 or 2, wherein: storing the adjustment value corresponding to the temperature of the conveying mechanism, The center position of the substrate is measured using the adjustment value corresponding to a path along which the substrate is conveyed and a temperature of the conveying mechanism.

4. A substrate conveying system, characterized in that: include: a conveying mechanism having a holding portion for holding a substrate and capable of conveying the substrate; a measuring unit that detects an outer edge of the substrate conveyed by the conveying mechanism and measures a center position of the substrate; and a control unit for controlling the conveying mechanism, The holding portion has a protrusion that protrudes beyond the held substrate. When conveying the substrate, the control unit uses the measuring unit to detect the outer edge of the protruding portion at a measuring position located on a path for conveyance to a target position to measure a reference position of the holding portion, and uses the measuring unit to detect the outer edge of the substrate at the measuring position to measure a center position of the substrate, corrects the target position based on an offset between the center position of the substrate and the reference position of the holding portion, and controls the conveying mechanism so that the reference position of the holding portion becomes the corrected target position.

5. The substrate transport system according to claim 4, wherein: The outer edge of the protrusion has an arc shape centered on a reference position of the holding portion.

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