Substrate processing equipment and substrate processing method

Abstract

To provide substrate processing equipment and a substrate processing method, each enabling appropriate detection of the position of the edge of a transparent substrate.SOLUTION: Substrate processing equipment comprises an optical sensor 46 and a control unit. The optical sensor 46 emits and receives inspection light at detection positions P1 and P2 on the path of movement of a substrate W, and outputs a light blocking signal when the amount of received inspection light falls below a threshold value. When the substrate W moves away from the detection position P1, the control unit detects the position of the edge E of the substrate W on the basis of the end of the light blocking signal. When the substrate W approaches the detection position P2, the control unit detects the position of the edge E of the substrate W on the basis of the beginning of the light blocking signal. This makes it possible to detect the position of the edge E of the substrate W on the basis of the signal of the part of the light blocking signal which is output near the edge E of the substrate W which is closest to the outside of the substrate W. Therefore, the substrate processing equipment can appropriately detect the position of the edge E of the transparent substrate W.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a substrate processing apparatus and a substrate processing method for processing a transparent substrate. [Background technology]

[0002] Conventionally, in manufacturing processes for substrates such as semiconductor wafers and liquid crystal displays, substrate processing apparatuses are used that perform a number of processes on substrates, such as coating with processing liquid, developing, heat treatment, and cleaning. In this type of apparatus, substrates are transported between a number of processing units by a transport robot. A conventional substrate processing apparatus having a transport robot is described in, for example, Patent Document 1. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2018-133415 A Summary of the Invention [Problem to be solved by the invention]

[0004] A conventional transport robot has a transmission-type optical sensor that detects the position of the edge of the substrate. The optical sensor emits inspection light from a light-transmitting device located below the transport path of the substrate toward a light-receiving device located above the transport path. The control unit recognizes the time when the light-receiving device switches between receiving and not receiving the inspection light as the time when the edge of the substrate has passed.

[0005] However, when the substrate to be processed is transparent, the inspection light of the optical sensor passes through the substrate without being blocked by the substrate, which makes it difficult to accurately detect the edge of the transparent substrate using the conventional method.

[0006] The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a substrate processing apparatus and a substrate processing method capable of appropriately detecting the edge position of a transparent substrate. [Means for solving the problem]

[0007] In order to solve the above problems, the first invention of the present application is a substrate processing apparatus for processing transparent substrates, comprising a hand for holding the substrate, a forward / backward mechanism for moving the hand forward / backward along a predetermined forward / backward path, an optical sensor for projecting and receiving inspection light at a detection position on the forward / backward path and outputting a light-shielding signal when the amount of inspection light received falls below a threshold value, and a control unit for detecting the position of an edge of the substrate based on the light-shielding signal, wherein when the substrate approaches the detection position, the control unit detects the position of the edge of the substrate based on the starting end of the light-shielding signal, and when the substrate moves away from the detection position, the control unit detects the position of the edge of the substrate based on the ending end of the light-shielding signal.

[0008] A second invention of the present application is a substrate processing apparatus of the first invention, wherein the advance / retract mechanism advances and retreats the hand between an origin position for storing the substrate and a transfer position for transferring the substrate, and the control unit detects the position of the edge of the substrate as the hand moves from the transfer position to the origin position.

[0009] A third aspect of the present invention is the substrate processing apparatus of the second aspect, wherein the optical sensor is positioned in the vicinity of the origin position.

[0010] A fourth invention of the present application is a substrate processing apparatus according to any one of the first to third inventions, wherein the optical sensor has a first optical sensor that detects a rear end in the movement direction of the substrate at a first detection position on the advance / retract path, and a second optical sensor that detects a front end in the movement direction of the substrate at a second detection position closer to the origin position than the first detection position.

[0011] A fifth invention of the present application is a substrate processing apparatus according to any one of the first to fourth inventions, wherein the control unit calculates a relative position of the substrate with respect to the hand based on the detected edge position.

[0012] A sixth invention of the present application is a substrate processing apparatus of the fifth invention, comprising a plurality of processing units and a transport robot which transports a substrate between the plurality of processing units, wherein the transport robot has the hand, the advance / retract mechanism, and the optical sensor, and the control unit calculates the relative position when transporting a substrate from one processing unit, and adjusts the position of the hand based on the relative position when transporting the substrate into another processing unit.

[0013] A seventh invention of the present application is a substrate processing method for processing a transparent substrate, comprising a signal output step of projecting and receiving inspection light at a detection position on a substrate's forward / backward path, and outputting a light-shielding signal when the amount of inspection light received falls below a threshold value, and a detection step of detecting the position of the substrate's edge based on the light-shielding signal, in which, when the substrate approaches the detection position, the position of the substrate's edge is detected based on the starting end of the light-shielding signal, and when the substrate moves away from the detection position, the position of the substrate's edge is detected based on the ending end of the light-shielding signal. Effect of the Invention

[0014] According to the first to seventh aspects of the present invention, the position of the edge of the substrate is detected based on the signal of the portion closest to the outer side of the substrate among the light-shielding signals outputted near the edge of the substrate, thereby making it possible to appropriately detect the position of the edge of the transparent substrate.

[0015] In particular, according to the third aspect of the present invention, the position of the edge of the substrate is detected when the substrate moving speed is decreasing immediately before the hand is stopped at the origin position, thereby enabling the position of the edge of the substrate to be detected with higher accuracy.

[0016] In particular, according to the fourth aspect of the present invention, the rear end and the front end of the substrate are detected by separate optical sensors. This makes it possible to obtain a light-shielding signal only near the edge of the substrate. Therefore, the position of the substrate edge can be detected without considering the light-shielding signal due to the pattern near the center of the substrate.

[0017] In particular, according to the sixth aspect of the present invention, the substrate can be accurately positioned in a predetermined position when it is transported into another processing unit, by taking into account the relative position of the substrate with respect to the hand when the substrate is transported out of one processing unit. [Brief description of the drawings]

[0018] [Figure 1] FIG. 2 is a plan view of the substrate processing apparatus. [Diagram 2] FIG. 2 is a control block diagram of the substrate processing apparatus. [Diagram 3] FIG. [Figure 4] FIG. [Diagram 5] 13 is a flowchart showing the flow of operations performed by a transfer robot when transferring a substrate from a first processing unit to a second processing unit. [Figure 6] 10 is a flowchart showing a process flow for detecting the position of a substrate. [Figure 7] FIG. 13 is a diagram showing the positional relationship between the optical sensor and the substrate in step S11. [Figure 8] FIG. 13 is a diagram showing the positional relationship between the optical sensor and the substrate in step S11. [Figure 9] FIG. 13 is a diagram showing the positional relationship between the optical sensor and the substrate in step S11. [Figure 10] FIG. 13 is a diagram showing the positional relationship between the optical sensor and the substrate in step S11. [Figure 11] FIG. 13 is a diagram showing the positional relationship between the optical sensor and the substrate in step S11. [Figure 12] 11 is a graph showing an example of a signal output from an optical sensor. [Figure 13] 11 is a graph showing an example of a signal output from an optical sensor. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.

[0020] <1. Overall configuration of substrate processing equipment> 1 is a plan view of a substrate processing apparatus 1 according to an embodiment of the present invention. The substrate processing apparatus 1 is an apparatus that performs processes such as coating of a processing liquid, development, heat treatment, and cleaning on a transparent, disk-shaped substrate W. The substrate W is, for example, a substrate for a liquid crystal display. However, the substrate W may also be a carrier substrate for supporting a silicon wafer. The material of the substrate W may be glass or silicon carbide (SiC). The substrate W may be colorless and transparent, or colored and transparent.

[0021] As shown in Fig. 1, the substrate processing apparatus 1 includes an indexer block 10, a processing block 20, and a controller 30. The indexer block 10 and the processing block 20 are disposed adjacent to each other on a horizontal floor surface. Hereinafter, the direction in which the indexer block 10 and the processing block 20 are aligned is referred to as a "first direction." Also, the horizontal direction perpendicular to the first direction is referred to as a "second direction."

[0022] The indexer block 10 is a portion for loading unprocessed substrates W from the outside and unloading processed substrates W to the outside. As shown in FIG. 1, the indexer block 10 has a plurality of (e.g., four) carrier placement parts 11 and a first transport part 12. The plurality of carrier placement parts 11 are arranged in a second direction. A carrier C that accommodates a plurality of substrates W can be set on each carrier placement part 11. For example, a FOUP (front opening unified pod) is used as the carrier C.

[0023] The first transport section 12 is located between the multiple carrier placement sections 11 and the processing block 20. The first transport section 12 has a first transport path 121 extending in the second direction, and a transport robot 40. The transport robot 40 is movable in the second direction along the first transport path 121.

[0024] The first transfer section 12 transfers the substrate W between the carrier C and a buffer 21 described below while holding the substrate W with the transfer robot 40. That is, the transfer robot 40 of the first transfer section 12 takes out the unprocessed substrate W from the carrier C and transfers it to the buffer 21. In addition, the transfer robot 40 of the first transfer section 12 takes out the processed substrate W from the buffer 21 and transfers it to the carrier C.

[0025] The processing block 20 is a site for performing various processes on the multiple substrates W transported from the indexer block 10. As shown in Fig. 1, the processing block 20 has a buffer 21, a second transport section 22, and multiple processing units 23. The buffer 21 is a unit that temporarily stores the substrates W between the first transport section 12 and the second transport section 22. The buffer 21 is capable of simultaneously storing multiple substrates W.

[0026] The second transfer section 22 has a second transfer path 221 extending in the first direction and a transfer robot 40. The transfer robot 40 is movable in the first direction along the second transfer path 221. The second transfer section 22 transfers the substrate W between the buffer 21 and the multiple processing units 23 while holding the substrate W with the transfer robot 40. That is, the transfer robot 40 of the second transfer section 22 takes out the unprocessed substrate W from the buffer 21 and transports it to the first processing unit 23. The transfer robot 40 of the second transfer section 22 also transports the substrate W sequentially between the multiple processing units 23. The transfer robot 40 of the second transfer section 22 also takes out the processed substrate W from the last processing unit 23 and transports it to the buffer 21.

[0027] The processing block 20 may have two or more second transport parts 22. For example, the second transport paths 221 may be provided in multiple stages in the vertical direction, and the transport robot 40 may be provided in each second transport path 221.

[0028] The processing units 23 are so-called single-piece processing units which process the substrates W one by one. The multiple processing units 23 are arranged on both sides in the second direction of the second transport path 221. The multiple processing units 23 include multiple types of processing units, such as a liquid processing unit which supplies a processing liquid while rotating the substrate W, a heating processing unit which heats the substrate W, and a cooling processing unit which cools the substrate W.

[0029] 1, a total of four processing units 23 are arranged, two on each side of the second transport path 221. However, the number of processing units 23 arranged on both sides of the second transport path 221 is not limited to the example of Fig. 1. In addition, multiple processing units 23 may be provided in multiple stages in the height direction.

[0030] The control unit 30 is an information processing device that controls each part of the substrate processing apparatus 1. Fig. 2 is a control block diagram of the substrate processing apparatus 1. As conceptually shown in Fig. 2, the control unit 30 is composed of a computer having a processor 31 such as a CPU, a memory 32 such as a RAM, and a storage unit 33 such as a hard disk drive. A control program P is stored in the storage unit 33. The control program P is a computer program for controlling the operation of each part of the substrate processing apparatus 1 in order to process the substrate W.

[0031] 2, the control unit 30 is electrically connected to the first transfer unit 12 and the second transfer unit 22 described above. That is, the control unit 30 is electrically connected to each of the transfer robots 40 of the first transfer unit 12 and the second transfer unit 22. The control unit 30 is also electrically connected to the substrate rotation mechanism, the processing liquid supply mechanism, the temperature adjustment mechanism, and the like of the multiple processing units 23. The control unit 30 controls the operation of each of the above-mentioned units according to a control program P stored in the storage unit 33. As a result, various processes including the transportation of the substrate W in the substrate processing apparatus 1 proceed.

[0032] <2. Transport control of transport robots> Next, a more detailed description will be given of the transport control of the substrate W by the transport robot 40. Fig. 3 is a side view of the transport robot 40. As shown in Fig. 3, the transport robot 40 includes a base unit 41, a rotating table 42, a hand 43, a forward / backward mechanism 44, a bracket 45, and a plurality of optical sensors 46.

[0033] The base unit 41 is located below the turntable 42. The base unit 41 moves horizontally along the first transport path 121 or the second transport path 221. The turntable 42 is rotatably supported by the base unit 41. A rotation mechanism having a motor is provided between the base unit 41 and the turntable 42. When the rotation mechanism is operated, the turntable 42 rotates about an axis extending in the vertical direction.

[0034] The hand 43 is a holder that holds the substrate W. The hand 43 is located above the rotating table 42. Fig. 4 is a top view of the hand 43. As shown in Fig. 4, the hand 43 has a hand body 431 that is substantially arc-shaped when viewed from above, and three suction portions 432 that extend inward from the hand body 431. In Fig. 4, the substrate W held by the hand 43 is indicated by a virtual line (two-dot chain line).

[0035] 4, the substrate W is placed inside the arc-shaped hand body 431, and placed on the upper surfaces of the three suction portions 432. The lower surface of the substrate W is suctioned to the suction holes 433 provided in the suction portions 432. This causes the position of the substrate W relative to the hand 43 to be fixed.

[0036] 4, the inner diameter of the hand body 431 is slightly larger than the outer diameter of the substrate W. For this reason, the position of the substrate W relative to the hand 43 is not strictly constant. The position of the substrate W relative to the hand 43 may shift within the range of a minute gap between the hand body 431 and the substrate W.

[0037] The advancing / retreating mechanism 44 is a mechanism for advancing / retreating the hand 43 along a horizontal advancing / retreating path. For example, a mechanism for converting a rotational motion output from a motor into a linear motion via a ball screw is used for the advancing / retreating mechanism 44. The advancing / retreating mechanism 44 moves the hand 43 forward and backward between an origin position (position indicated by a solid line in FIG. 3) where the substrate W is stored between the rotating table 42 and the bracket 45, and a transfer position (position indicated by a two-dot chain line in FIG. 3) protruding forward from the origin position. When the transport robot 40 moves along the first transport path 121 or the second transport path 221, the hand 43 is disposed at the origin position. When the transport robot 40 transfers the substrate W to and from a substrate holder in the processing unit 23, the hand 43 is disposed at the transfer position.

[0038] The bracket 45 is a frame for holding light receivers 462 (to be described later) of the multiple optical sensors 46. The bracket 45 is fixed to the rotating base 42.

[0039] The four optical sensors 46 are transmission type sensors for detecting the position of the edge E of the substrate W on the path of movement of the substrate W. Fig. 4 shows the positions of the optical sensors 46 when the hand 43 is placed at the origin position. As shown in Fig. 4, the four optical sensors 46 are placed in the vicinity of the hand 43 placed at the origin position.

[0040] The multiple optical sensors 46 include two first optical sensors 46A and two second optical sensors 46B. The two first optical sensors 46A are disposed at a first detection position P1 on the path of movement of the substrate W. The first detection position P1 is a position slightly closer to the transfer position than the substrate W held by the hand 43 disposed at the origin position. The two second optical sensors 46B are disposed at a second detection position P2 closer to the origin position than the first detection position P1. The two second optical sensors 46B are disposed at positions overlapping with the substrate W held by the hand 43 disposed at the origin position in a top view.

[0041] 3, each of the four optical sensors 46 has a light projector 461 and a light receiver 462. The light projector 461 is fixed to the rotating base 42. The light receiver 462 is fixed to the bracket 45. The light projector 461 emits inspection light toward the light receiver 462. If there is no light blocking object between the light projector 461 and the light receiver 462, the inspection light emitted from the light projector 461 is received by the light receiver 462. If there is a light blocking object between the light projector 461 and the light receiver 462, the amount of inspection light received by the light receiver 462 decreases.

[0042] Figure 5 is a flowchart showing the operation flow when the transport robot 40 of the second transport section 22 transports a substrate W from one processing unit 23 (hereinafter referred to as the "first processing unit 23A") to another processing unit 23 (hereinafter referred to as the "second processing unit 23B").

[0043] 5, the transport robot 40 first takes out the substrate W from the first processing unit 23A (step S1). Specifically, the transport robot 40 first moves along the second transport path 221 to the front of the first processing unit 23A. Next, the transport robot 40 rotates the turntable 42 to orient the tip of the hand 43 toward the first processing unit 23A. Next, the transport robot 40 moves the hand 43 from the origin position to the transfer position by the forward / backward mechanism 44. Then, the transport robot 40 holds the substrate W arranged in the first processing unit 23A by placing it on the suction portion 432 of the hand 43 and suctioning it.

[0044] Thereafter, the transport robot 40 moves the hand 43 holding the substrate W from the transfer position to the origin position. As a result, the substrate W is unloaded from the first processing unit 23A. At this time, as described above, the position of the substrate W relative to the hand 43 may be slightly deviated from the ideal position. Therefore, in this substrate processing apparatus 1, a process is executed in which the multiple optical sensors 46 detect the relative position of the substrate W with respect to the hand 43 while the hand 43 is moving from the transfer position to the origin position.

[0045] FIG. 6 is a flow chart showing the flow of a process for detecting the position of the substrate W. As shown in FIG. 6, the control unit 30 first acquires signals output from the multiple optical sensors 46 as the substrate W moves (step S11: signal output process). FIGS. 7 to 11 are diagrams showing the positional relationship between the optical sensors 46 and the substrate W in step S11. FIG. 12 is a graph showing an example of signals output from the first optical sensor 46A and the second optical sensor 46B in step S11. The horizontal axis of FIG. 12 indicates time. The vertical axis of FIG. 12 indicates the signal level.

[0046] 7 to 11, the substrate W moves toward the origin position between the light projectors 461 and light receivers 462 of the multiple optical sensors 46 whose positions are fixed with respect to the rotating table 42. The position of the hand 43 holding the substrate W in the state of FIG. 11 is the origin position. In this embodiment, the multiple optical sensors 46 detect the edge E of the substrate W immediately before the substrate W stops at the origin position.

[0047] After the front end of the substrate W in the moving direction passes through the first optical sensor 46A, as shown in Fig. 7, the main surface (the surface with the largest area) of the substrate W moves between the light projector 461 and the light receiver 462 of the first optical sensor 46A. At this time, since the substrate W is transparent, the inspection light emitted from the light projector 461 passes through the substrate W and is received by the light receiver 462. In this case, as in the period t1 in Fig. 12, the signal output from the first optical sensor 46A becomes a Low signal. The Low signal is a light transmission signal indicating light transmission.

[0048] Furthermore, in the period t1, in the second optical sensor 46B as well, the inspection light emitted from the light projector 461 is incident on the light receiver 462. Therefore, in the period t1, the signal output from the second optical sensor 46B is also a Low signal.

[0049] A chamfered bevel portion B is provided near an edge E of the substrate W. When the hand 43 holds the substrate W so that the main surface is horizontal, the surface of the bevel portion B is inclined with respect to the horizontal plane.

[0050] After the state of FIG. 7, as shown in FIG. 8, the bevel portion B at the rear end in the moving direction of the substrate W passes between the light projector 461 and the light receiver 462 of the first optical sensor 46A. At this time, a part of the inspection light emitted from the light projector 461 of the first optical sensor 46A is refracted or reflected at the bevel portion B and deviates from the optical axis. Therefore, the amount of the inspection light received by the light receiver 462 of the first optical sensor 46A becomes lower than a preset threshold value. In this case, as in the period t2 of FIG. 12, the signal output from the first optical sensor 46A becomes a High signal. The High signal is a light blocking signal indicating light blocking.

[0051] On the other hand, in the second optical sensor 46B, even during the period t2, the inspection light emitted from the light projector 461 is incident on the light receiver 462. Therefore, the signal output from the second optical sensor 46B remains a Low signal during the period t2.

[0052] In this embodiment, the distance between the first optical sensor 46A and the second optical sensor 46B in the movement direction of the substrate W is greater than the length of the substrate W in the movement direction. Therefore, after the substrate W passes the first optical sensor 46A, the substrate W is disposed at a position that does not overlap with either the first optical sensor 46A or the second optical sensor 46B, as shown in FIG. 9. In this case, in both the first optical sensor 46A and the second optical sensor 46B, the inspection light emitted from the light projector 461 is incident on the light receiver 462. Therefore, as in the period t3 in FIG. 12, the signal output from the first optical sensor 46A and the signal output from the second optical sensor 46B are both Low signals.

[0053] 9, as shown in FIG. 10, the bevel portion B at the front end in the moving direction of the substrate W passes between the light projector 461 and the light receiver 462 of the second optical sensor 46B. At this time, a part of the inspection light emitted from the light projector 461 of the second optical sensor 46B is refracted or reflected at the bevel portion B and deviates from the optical axis. As a result, the amount of inspection light received by the light receiver 462 of the second optical sensor 46B becomes lower than a preset threshold value. In this case, as in the period t4 of FIG. 12, the signal output from the second optical sensor 46B becomes a High signal.

[0054] On the other hand, in the first optical sensor 46A, during the period t4, the inspection light emitted from the light projector 461 is incident on the light receiver 462. Therefore, the signal output from the first optical sensor 46A during the period t4 is a Low signal.

[0055] 11, the main surface (the surface with the largest area) of the substrate W moves between the light projector 461 and the light receiver 462 of the second optical sensor 46B. Then, since the substrate W is transparent, the inspection light emitted from the light projector 461 passes through the substrate W and is received by the light receiver 462. In this case, the signal output from the second optical sensor 46B becomes a Low signal, as in the period t5 in FIG.

[0056] Furthermore, in the period t5, in the first optical sensor 46A as well, the inspection light emitted from the light projector 461 is incident on the light receiver 462. Therefore, in the period t5, the signal output from the first optical sensor 46A also becomes a Low signal.

[0057] Returning to Fig. 6, the control unit 30 acquires the above-mentioned signals from the multiple optical sensors 46, and then detects the position of the edge E of the substrate W based on the signals (step S12: detection step). The edge E is the outermost periphery of the substrate W. In other words, the edge E is the outermost part of the bevel portion B.

[0058] The control unit 30 determines that the end portion indicated by the dashed arrow in the High signal from the first optical sensor 46A in Fig. 12 is a signal corresponding to the edge E at the rear end in the movement direction of the substrate W. This is because, in a situation in which the substrate W moves away from the first detection position P1 as in Fig. 8, the edge E of the bevel portion B is the last to pass through the first detection position P1.

[0059] Based on the time ta of the end of this High signal, the control unit 30 detects the position of the edge E of the rear end in the movement direction of the substrate W. More specifically, the control unit 30 stores in the memory unit 33 the count value of the pulse signal output from the encoder provided in the advance / retract mechanism 44 at the time ta of the end of the High signal as a count value corresponding to the edge E of the rear end of the substrate W. Then, the control unit 30 calculates the relative position of the edge E of the rear end of the substrate W with respect to the position of the hand 43 at that time ta.

[0060] Furthermore, the control unit 30 determines that the starting end indicated by the dashed arrow in the High signal from the second optical sensor 46B in Fig. 12 is a signal corresponding to the edge E of the front end in the movement direction of the substrate W. This is because, as in Fig. 10, in a situation in which the substrate W approaches the second detection position P2, the edge E of the bevel portion B passes through the second detection position P2 first.

[0061] Based on time tb of the start end of this High signal, the control unit 30 detects the position of the edge E of the front end in the movement direction of the substrate W. More specifically, the control unit 30 stores in the memory unit 33 the count value of the pulse signal output from the encoder provided in the advance / retract mechanism 44 at time tb of the front end of the High signal as a count value corresponding to the edge E of the front end of the substrate W. Then, the control unit 30 calculates the relative position of the edge E of the front end of the substrate W with respect to the position of the hand 43 at that time tb.

[0062] 4, the transfer robot 40 has two sets of the first optical sensor 46A and the second optical sensor 46B. In step S12, the control unit 30 detects the relative position of the edge E with respect to the hand 43 based on the signals output from these four optical sensors 46. As a result, the relative positions of the four edges E of the substrate W with respect to the hand 43 are detected.

[0063] Next, the control unit 30 calculates the relative position of the center of the substrate W with respect to the hand 43 based on the obtained positions of the four edges E (step S13). The center position of the substrate W can be calculated if the positions of at least three edges E are known. However, the substrate W may have a notch (cutout) at one of the edges E. For this reason, in this embodiment, the control unit 30 calculates the position of the center of the substrate W based on the positions of the four edges E. In this way, even if one of the detected four edges E is a notch, the position of the center of the substrate W can be calculated with high accuracy based on the positions of the other three edges E. The control unit 30 stores the calculated relative position of the center of the substrate W with respect to the hand 43 in the memory unit 33.

[0064] Returning to FIG. 5, after the substrate W has been removed from the first processing unit 23A, the transport robot 40 then transports the substrate W into the second processing unit 23B (step S2). Specifically, the transport robot 40 moves from in front of the first processing unit 23A along the second transport path 221 to in front of the second processing unit 23B. Next, the transport robot 40 rotates the turntable 42 to orient the tip of the hand 43 toward the second processing unit 23B. Next, the transport robot 40 moves the hand 43 from the origin position to the transfer position by the advancing and retreating mechanism 44. Then, the transport robot 40 releases the adsorption of the substrate W by the adsorption portion 432, and delivers the substrate W to a predetermined position in the second processing unit 23B.

[0065] At this time, the control unit 30 fine-adjusts the position of the hand 43 based on the relative position of the substrate W with respect to the hand 43 calculated in step S13 described above. For example, if the relative position of the substrate W with respect to the hand 43 is shifted in the + direction from the ideal position, the position of the hand 43 is fine-adjusted to the - side. Also, if the relative position of the substrate W with respect to the hand 43 is shifted in the - direction from the ideal position, the position of the hand 43 is fine-adjusted to the + side. This allows the substrate W to be placed at a predetermined position in the second processing unit 23B with greater accuracy.

[0066] As described above, in this substrate processing apparatus 1, when the substrate W moves away from the detection position of the optical sensor 46, the position of the edge E of the substrate W is detected based on the ending part of the High signal, and when the substrate W approaches the detection position of the optical sensor 46, the position of the edge E of the substrate W is detected based on the starting part of the High signal. In this manner, the position of the edge E of the substrate W can be detected based on the signal of the part of the High signal outputted in the vicinity of the edge E of the substrate W that is closest to the outside of the substrate W. This allows the position of the edge E of the transparent substrate W to be properly detected.

[0067] Particularly, in this embodiment, the multiple optical sensors 46 are located near the origin position in the movement direction of the hand 43. Specifically, the multiple optical sensors 46 are located at a location closer to the origin position than the midpoint between the origin position and the transfer position. In this way, the position of the edge E of the substrate W can be detected when the movement speed of the substrate W is decreasing immediately before the hand 43 is stopped at the origin position. This allows the position of the edge E of the substrate W to be detected with greater accuracy.

[0068] In this embodiment, the multiple optical sensors 46 include a first optical sensor 46A that detects the rear end of the substrate W in the moving direction, and a second optical sensor 46B that detects the front end of the substrate W in the moving direction. In this way, if the rear end and the front end of the substrate W are detected by separate optical sensors 46A and 46B, signals only in the vicinity of the edge E of the substrate W can be obtained from each optical sensor 46A and 46B in a short time. Therefore, even if the substrate W has a light-shielding pattern near the center, it is not necessary to distinguish between a High signal due to the light-shielding pattern and a High signal due to the bevel portion B of the substrate W. Therefore, the position of the edge E of the substrate W can be easily detected based on the High signal due to the bevel portion B of the substrate W.

[0069] <3. Modifications> Although one embodiment of the present invention has been described above, the present invention is not limited to the above embodiment.

[0070] 12, the first optical sensor 46A and the second optical sensor 46B output signals only from the vicinity of the edge E of the substrate W to the control unit 30. However, for example, as shown in FIG 13, the signals output from the first optical sensor 46A and the second optical sensor 46B may include a High signal due to a light-shielding pattern on the inner side of the bevel portion B of the substrate W.

[0071] Even in this case, when the substrate W is moving away from the first detection position P1, the control unit 30 only needs to detect the position of the edge E of the substrate W based on the trailing end of the High signal (time ta). When the substrate W is approaching the second detection position P2, the control unit 30 only needs to detect the position of the edge E of the substrate W based on the starting end of the High signal (time tb).

[0072] In the above embodiment, the optical sensor 46 detects the edge E of the substrate W while the hand 43 is moving from the transfer position to the origin position. However, the optical sensor 46 may detect the edge E of the substrate W while the hand 43 is moving from the origin position to the transfer position.

[0073] 12, the signal output from the first optical sensor 46A and the signal output from the second optical sensor 46B are shown in separate graphs. However, if the High signal from the first optical sensor 46A and the High signal from the second optical sensor 46B are not output simultaneously, the output signals from these two optical sensors 46A and 46B may be input to an OR circuit and a combined signal may be output. In this way, the number of wirings can be reduced while a single output signal can obtain the High signal from the first optical sensor 46A and the High signal from the second optical sensor 46B.

[0074] Also, in the above embodiment, the substrate W has the bevel portion B. However, the substrate W does not have to have the bevel portion B. For example, the edge E of the substrate W may be a vertical surface without a taper. Even in this case, a high signal can be obtained for a short period of time due to the scattering of the inspection light in the vicinity of the edge E of the substrate W. Therefore, based on the high signal, the position of the edge E of the substrate W can be detected by a method similar to that of the above embodiment.

[0075] In the above embodiment, the operation of the transport robot 40 of the second transport section 22 is described when the transport robot 40 transports the substrate W between the two processing units 23. However, the transport robot 40 of the second transport section 22 may perform a similar transport process to the above when the transport robot 40 transports the substrate W between the buffer 21 and the processing unit 23. In addition, the transport robot 40 of the first transport section 12 may perform a similar transport process to the above when the transport robot 40 transports the substrate W between the carrier C and the buffer 21.

[0076] In the above embodiment, the light projector 461 of the optical sensor 46 is disposed below the advance / retract path of the substrate W, and the light receiver 462 of the optical sensor 46 is disposed above the advance / retract path of the substrate W. However, the light projector 461 of the optical sensor 46 may be disposed above the advance / retract path of the substrate W, and the light receiver 462 of the optical sensor 46 may be disposed below the advance / retract path of the substrate W.

[0077] Furthermore, some of the elements appearing in the above-described embodiments and modifications may be omitted or other elements may be added without departing from the spirit of the present invention. [Explanation of symbols]

[0078] 1. Substrate Processing Equipment 12 First conveyor section 22 Second conveyor section 23 Processing Unit 30 Control section 40 Transport Robot 43 Hands 44 Advancement / retraction mechanism 46 Optical Sensor 46A 1st optical sensor 46B Second optical sensor 431 Hand body 432 Adsorption part 461 Floodlight 462 Photoreceiver W substrate B Bevel E-edge P1 First detection position P2 Second detection position

Claims

1. A substrate processing apparatus for processing a transparent substrate, comprising: A hand for holding a substrate; a reciprocating mechanism for moving the hand along a predetermined reciprocating path; an optical sensor that projects and receives an inspection light at a detection position on the advance / retract path and outputs a light blocking signal when an amount of the received inspection light falls below a threshold; a control unit that detects the position of an edge of the substrate based on the light blocking signal; Equipped with The control unit is When the substrate approaches the detection position, the position of the edge of the substrate is detected based on the leading edge of the light blocking signal; When the substrate moves away from the detection position, the substrate processing apparatus detects the position of the edge of the substrate based on the trailing end of the light blocking signal.

2. The substrate processing apparatus according to claim 1 , the advancing / retracting mechanism moves the hand back and forth between an origin position where the substrate is stored and a transfer position where the substrate is transferred; The control unit detects a position of an edge of the substrate while the hand is moving from the transfer position to the origin position.

3. The substrate processing apparatus according to claim 2, The optical sensor is located near the origin position.

4. The substrate processing apparatus according to claim 3, The optical sensor includes: a first optical sensor that detects a rear end of the substrate in a moving direction at a first detection position on the advance / retract path; a second optical sensor that detects a front end of the substrate in a moving direction at a second detection position that is closer to the origin position than the first detection position; The substrate processing apparatus includes:

5. The substrate processing apparatus according to any one of claims 1 to 4, The control unit calculates a relative position of the substrate with respect to the hand based on the detected edge position.

6. The substrate processing apparatus according to claim 5 , A plurality of processing units; a transfer robot that transfers substrates among the plurality of processing units; Equipped with the transport robot has the hand, the advancing / retreating mechanism, and the optical sensor; The control unit is Calculating the relative position when unloading the substrate from one of the processing units; The substrate processing apparatus adjusts the position of the hand based on the relative position when the substrate is carried into another processing unit.

7. A substrate processing method for processing a transparent substrate, comprising the steps of: a signal output step of projecting and receiving an inspection light at a detection position on a path of movement of the substrate, and outputting a light blocking signal when an amount of the inspection light received falls below a threshold value; a detection step of detecting a position of an edge of the substrate based on the light blocking signal; having In the detection step, When the substrate approaches the detection position, the position of the edge of the substrate is detected based on the leading edge of the light blocking signal; A substrate processing method comprising: detecting a position of an edge of a substrate based on a trailing end of the light blocking signal when the substrate moves away from the detection position.

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