Substrate information acquisition device and substrate processing apparatus

Abstract

A light emission unit (61) of a substrate information acquisition device (60) emits illumination light (610), which is configured in a planar shape perpendicular to the vertical direction, toward the inside of a housing container (7) through a container opening (71) provided in a lateral surface on the front side of the housing container (7). The vertical thickness of the illumination light (610) is smaller than the vertical pitch (P1) of a plurality of substrates (9). A light-receiving unit (62) receives reflected light reflected by the inner surface (73) of the housing container (7). The light-receiving unit (62) has an optical axis that is at the same vertical position as that of the illumination light (610). A movement mechanism moves the illumination light (610) and the light-receiving unit (62) relative to the housing container (7) in the vertical direction. An information acquisition unit acquires information about the shapes and positions of the plurality of substrates (9) on the basis of an output that is continuously outputted from the light-receiving unit (62) in parallel with the relative movement of the light-receiving unit (62) and the illumination light (610) by the movement mechanism.

Description

Substrate information acquisition device and substrate processing device

[0001] The present invention relates to a technique for acquiring information on the shape and position of a plurality of substrates arranged vertically and accommodated inside a storage container. [Reference to related applications] This application claims the benefit of priority from Japanese Patent Application JP2024-207473 filed on November 28, 2024, and all the disclosures of that application are incorporated herein.

[0002] In a substrate processing device that processes semiconductor substrates (hereinafter also simply referred to as "substrates"), a plurality of substrates arranged vertically and accommodated inside a storage container such as a FOUP (Front Opening Unified Pod) are carried out by a robot provided in an indexable block through the opening of the storage container. The substrate carried out from the storage container is subjected to various processes in a processing block and then carried into and accommodated in the storage container by the above robot.

[0003] In such a substrate processing device, before inserting the robot's hand into the storage container, the presence or absence of substrates at each stage inside the storage container is detected by a mapping sensor. The mapping sensor includes, for example, optical sensors arranged on both the left and right sides of the substrate end near the opening of the storage container, and the position where the detection light is blocked by the substrate end is acquired as the position of the substrate by moving the optical sensor in the vertical direction (see Japanese Patent Laid-Open No. 2004-214462 (Document 1) and Japanese Patent Laid-Open No. 2012-235058 (Document 2)).

[0004] Further, in Japanese Patent Laid-Open No. 2023-30876 (Document 3), a technique has been proposed for imaging a plurality of substrates inside a storage container and acquiring the shape (for example, the degree of curvature upward or downward) and position of the plurality of substrates inside the storage container based on the captured image. Thereby, when the robot's hand enters the storage container, it is possible to suppress the hand from contacting another substrate adjacent to the lower side of the substrate to be carried out or the substrate to be carried out from contacting another substrate adjacent to the upper side of the substrate.

[0005] Incidentally, while the mapping sensors in References 1 and 2 can detect the position of the substrate edge near the opening of the containment container, they cannot detect the overall shape or position of the substrate (specifically, the degree of curvature of the substrate or its inclination within the containment container). Furthermore, while the technology in Reference 3 can acquire the shape and position of the substrate near the opening of the containment container with relatively good accuracy, the back of the containment container (i.e., the area away from the opening) is dark and difficult to focus on, making it difficult to acquire the shape and position of the substrate at the back of the containment container with good accuracy. Moreover, even if illumination light is shone into the inside of the containment container, the illumination light repeatedly reflects off the top and bottom surfaces of multiple substrates, making it difficult to acquire the shape and position of the substrate at the back of the containment container with good accuracy.

[0006] The present invention is directed towards a substrate information acquisition device and aims to accurately acquire information on the shape and position of multiple substrates in a storage container when viewed from the front.

[0007] One aspect of the present invention is a substrate information acquisition device for acquiring information on the shape and position of a plurality of substrates arranged vertically inside a storage container, comprising: a light emission unit that emits illumination light, which is configured as a vertically perpendicular planar shape and has a vertical thickness smaller than the vertical pitch of the plurality of substrates, toward the inside of the storage container through a container opening provided on the front side surface of the storage container; a light receiving unit that has the same optical axis as the illumination light in the vertical direction and receives reflected light reflected from the inner surface of the storage container; a movement mechanism that moves the illumination light and the light receiving unit relative to the storage container in the vertical direction; and an information acquisition unit that acquires information on the shape and position of the plurality of substrates based on an output continuously output from the light receiving unit in parallel with the relative movement of the illumination light and the light receiving unit by the movement mechanism.

[0008] According to the present invention, information on the shape and position of multiple substrates in a containment container in a front view can be acquired with high accuracy.

[0009] Aspect 2 of the present invention is a substrate information acquisition apparatus according to aspect 1, wherein the light emission unit comprises a sheet laser light source that emits the sheet-like illumination light.

[0010] A third aspect of the present invention is a substrate information acquisition device according to aspect 1 (or aspect 1 or 2), wherein the thickness of the illumination light in the vertical direction is thinner than the thickness of the substrate in the vertical direction.

[0011] Aspect 4 of the present invention is a substrate information acquisition device according to Aspect 1 (which may be any one of Aspects 1 to 3), wherein the width of the illumination light in the left-right direction is greater than the width of the substrate in the left-right direction at each position in the front-rear direction.

[0012] Aspect 5 of the present invention is a substrate information acquisition device according to aspect 1 (which may be any one of aspects 1 to 4), wherein the light receiving unit includes an area camera that captures a planar image of the inside of the containment container. In a plurality of captured images continuously captured by the area camera in parallel with the illumination light and the relative movement of the light receiving unit, only the central part in the vertical direction of each captured image is output to the information acquisition unit.

[0013] Aspect 6 of the present invention is a substrate processing apparatus for processing substrates, comprising: a substrate information acquisition apparatus according to any one of aspects 1 to 5; an indexer block on which a first transport robot for loading and unloading substrates into and out of the storage container is arranged; and a processing unit for processing substrates and a processing block on which a second transport robot for loading and unloading substrates into and out of the processing unit is arranged. The light emission unit, the light receiving unit and the moving mechanism of the substrate information acquisition apparatus are arranged in the indexer block.

[0014] Embodiment 7 of the present invention is a substrate processing apparatus according to Embodiment 6, wherein the light emitting unit and the light receiving unit of the substrate information acquisition apparatus are fixed to a substrate support unit that supports the substrate in the first transport robot. The moving mechanism of the substrate information acquisition apparatus moves the substrate support unit in the vertical direction in the first transport robot.

[0015] Embodiment 8 of the present invention is a substrate processing apparatus according to Embodiment 7, wherein the substrate support portion includes a substrate contact portion that extends in the front-rear direction below the substrate and directly contacts the lower surface of the substrate to support the substrate. The front principal point of the light receiving portion coincides in a plan view with a center line that extends linearly in the front-rear direction at the center of the left-right direction of the substrate contact portion.

[0016] Aspect 9 of the present invention is a substrate processing apparatus according to aspect 7 (or aspect 7 or 8), wherein the substrate support portion comprises a plurality of substrate contact portions, each extending in the front-rear direction below the substrate and directly contacting the lower surface of the substrate to support the substrate. The light receiving portion comprises a plurality of light receiving devices, each arranged at the same position in the left-right direction as the plurality of substrate contact portions.

[0017] The aforementioned objectives, as well as other objectives, features, embodiments, and advantages, will be revealed by the detailed description of the present invention below, with reference to the attached drawings.

[0018] This is a plan view of a substrate processing apparatus according to one embodiment. This is a side view showing the interior of the substrate processing apparatus. This is a longitudinal cross-sectional view of the area near the containment container. This is a longitudinal cross-sectional view of the area near the containment container. This is a front view of the area near the containment container. This is a diagram showing the configuration of the control unit. This is a plan view of the transport hand and the area near the containment container. This is a side view of the transport hand and the area near the containment container. This is a plan view of the transport hand and the area near the containment container. This is a side view of the transport hand and the area near the containment container. This is a diagram showing an example of an captured image. This is a diagram showing an example of an captured image. This is a diagram schematically showing substrate information inside the container. This is a diagram showing an example of an captured image. This is a diagram showing an example of an captured image. This is a side view of the transport hand and the area near the containment container.

[0019] Figure 1 is a plan view of a substrate processing apparatus 1 according to one embodiment of the present invention. Figure 2 is a view of the substrate processing apparatus 1 as seen from line II-II in Figure 1. In each of the figures referred to below, an XYZ Cartesian coordinate system is appropriately attached, in which the Z-axis direction is the vertical direction (i.e., up and down direction) and the XY plane is the horizontal plane. In Figure 1, the internal structure of the substrate processing apparatus 1 is also shown with solid lines. In Figure 2, a part of the (+X) side of the substrate processing apparatus 1 is omitted from the illustration.

[0020] The substrate processing apparatus 1 is a device that processes multiple substantially disc-shaped semiconductor substrates 9 (hereinafter simply referred to as "substrates 9") in succession. In the substrate processing apparatus 1, for example, a cleaning process is performed on the substrates 9.

[0021] The substrate processing apparatus 1 comprises an indexer block 10, a processing block 20, and a mounting unit 40. The indexer block 10 and the processing block 20 are also called indexer cells and processing cells, respectively. The indexer block 10 is also called an Equipment Front End Module (EDEM) unit, etc.

[0022] Multiple load ports 11 (for example, four) are arranged on the (-X) side of the indexer block 10. In the example shown in Figure 1, the multiple load ports 11, the indexer block 10, the mounting unit 40, and the processing block 20 are arranged adjacent to each other in this order, from the (-X) side to the (+X) side.

[0023] Multiple load ports 11 are arranged in the Y direction along the (-X) side wall 13 of the indexer block 10. Each of the multiple load ports 11 is a mounting platform on which a housing container 7 is placed. The housing container 7 houses multiple disc-shaped substrates 9 arranged in the vertical direction (i.e., the Z direction) in its internal space 70. The housing container 7 is, for example, a FOUP (Front Opening Unified Pod) that houses the substrates 9 in a sealed space. The housing container 7 is not limited to a FOUP and may be, for example, an SMIF (Standard Mechanical Interface) pod. The number of load ports 11 may be one or two or more.

[0024] Each load port 11 receives a storage container 7 containing multiple unprocessed substrates 9 (i.e., substrates 9 before processing by the substrate processing device 1), which is brought in from outside the substrate processing device 1 by an OHT (Overhead Hoist Transfer) or the like and placed on top of it. Processed substrates 9 that have finished processing in the processing block 20 are placed in the storage container 7 placed on the load port 11. The storage container 7 containing the processed substrates 9 is then transported out of the substrate processing device 1 by an OHT or the like. In other words, the load port 11 functions as a substrate accumulation unit that accumulates both unprocessed substrates 9 and processed substrates 9.

[0025] Figure 3 is a magnified longitudinal cross-sectional view of a portion near one of the containment containers 7. The side wall 13 on the (-X) side of the indexer block 10 is provided with a passage opening 131 at a position opposite the containment container 7 on each load port 11 in the X direction. The passage opening 131 is opened and closed by a sliding door 132 that can move vertically along the side wall 13. In Figure 3, the sliding door 132 is moved below the passage opening 131, showing the passage opening 131 in an open state. The shape of the passage opening 131 when viewed along the X direction is, for example, approximately rectangular.

[0026] On the (+X) side of the containment container 7 (i.e., the side facing the indexer block 10 in the X direction), there is a container opening 71 that faces the passage opening 131 in the X direction. The (+X) side of the containment container 7 is the side of the containment container 7 closer to the indexer block 10, and is the front side of the containment container 7 when viewed from the indexer block 10 side.

[0027] In the following explanation, the (+X) side of the containment container 7 will also be referred to as the "front side" or "forward side," and the (-X) side of the containment container 7 (i.e., the side of the containment container 7 furthest from the indexer block 10) will also be referred to as the "back side" or "rear side." Additionally, the X direction will also be referred to as the "front-back direction," and the Y direction will also be referred to as the "left-right direction."

[0028] The container opening 71 of the containment container 7 is opened and closed by a door (not shown). Figure 3 shows the state in which the door moves downward along with the sliding door 132, below the container opening 71 and the passage opening 131, and the container opening 71 is open. The shape of the container opening 71 when viewed along the X direction is, for example, approximately rectangular.

[0029] As shown in Figure 3, when the passage opening 131 and the container opening 71 are open, the internal space 70 of the storage container 7 and the internal space 100 of the indexer block 10 are in communication through the passage opening 131 and the container opening 71. Then, the indexer robot 12 (see Figures 1 and 2), which will be described later, loads the substrates 9 into and out of the storage container 7 through the passage opening 131 and the container opening 71. In the example shown in Figure 3, the number of substrates 9 stored in the internal space 70 of the storage container 7 is 25. The 25 substrates 9 are arranged vertically while being spaced apart from each other.

[0030] Figure 4 is a longitudinal cross-sectional view showing a portion near one of the containment containers 7. Figure 5 is a front view of the portion near the containment container 7, viewed from the (+X) side of the side wall 13 described above. Figures 4 and 5 also show components other than the containment container 7. In the internal space 70 of the containment container 7, each substrate 9 is supported by an internal support portion 72 provided on the inner surface 73 of the containment container 7. The internal support portion 72 is a substantially flat, protruding portion that extends substantially horizontally from the inner surface 73 of the containment container 7, and supports the substrate 9 by contacting the peripheral edge of the lower surface of the substrate 9 from below. Note that in Figures 3 to 5, some of the substrates 9 among the multiple substrates 9 inside the containment container 7 are not shown (the same applies to Figures 8, 10, and 14 described later).

[0031] In the substrate processing apparatus 1 shown in Figures 1 and 2, unprocessed substrates 9 are transferred from the storage container 7 to the processing block 20 via the indexer block 10 and the mounting unit 40. Processed substrates 9 processed in the processing block 20 are then transferred back to the storage container 7 via the mounting unit 40 and the indexer block 10. An indexer robot 12 is positioned in the internal space 100 of the indexer block 10 to load and unload the substrates 9 into and out of the storage container 7.

[0032] The indexer robot 12 comprises a substrate support section 120 and a moving mechanism 124. The substrate support section 120 is capable of supporting multiple substrates 9. The substrate support section 120 comprises multiple transport hands 121, a base 122, and a base support section 123. In the example shown in Figure 2, the substrate support section 120 comprises four transport hands 121. The four transport hands 121 are mounted on the base 122 in an arrangement that is spaced apart in the vertical direction. Each transport hand 121 supports and holds one substrate 9 from below.

[0033] The base 122 is attached to the base support 123. The base support 123 is provided with a rotation mechanism (not shown) that rotates the base 122 around a rotation axis that faces vertically. This rotation mechanism includes, for example, a motor. The base support 123 is connected to the moving mechanism 124. The moving mechanism 124 is a mechanism that moves the substrate support 120 in the Y direction (i.e., the direction in which the multiple housing containers 7 are arranged) and the Z direction (i.e., the vertical direction). The moving mechanism 124 includes, for example, a ball screw mechanism driven by a motor.

[0034] In the indexer robot 12, the multiple transport hands 121 may be able to move independently of each other, or some or all of the multiple transport hands 121 may move together without being able to move independently of each other. Also, the number of transport hands 121 may be one or two or more.

[0035] The indexer robot 12 is a first transport robot that loads and unloads substrates 9 into and out of a storage container 7, which is placed on a load port 11, by allowing the transport hand 121 to access the container 7. The indexer robot 12 also transfers substrates 9 between the storage container 7 and the mounting unit 40. The mechanism for moving each component in the indexer robot 12 is not limited to the example described above and can be modified in various ways.

[0036] The mounting unit 40 is provided at the connection point between the indexer block 10 and the processing block 20. Unprocessed substrates 9 that are to be transferred from the indexer block 10 to the processing block 20 are temporarily placed on the mounting unit 40. Processed substrates 9 that are to be transferred from the processing block 20 to the indexer block 10 are also temporarily placed on the mounting unit 40.

[0037] The processing block 20 is provided with a transport path 23 used for transporting substrates 9, and a plurality of processing units 21 arranged around the transport path 23. In the example shown in Figure 1, the transport path 23 extends in the X direction from the center in the Y direction of the processing block 20. A center robot 22, which is a second transport robot that loads and unloads substrates 9 to and from each processing unit 21, is arranged in the internal space 230 of the transport path 23. For example, 12 processing units 21 are arranged around the transport path 23. Each processing unit 21 is a single-sheet processing device that performs a predetermined processing, such as cleaning, on one substrate 9. The processing performed on the substrate 9 by the processing unit 21 can be varied.

[0038] The substrate processing apparatus 1 further includes a control unit 8 that controls the configurations of the indexer block 10, the mounting unit 40, and the processing block 20. Figure 6 is a diagram showing the configuration of the control unit 8. The control unit 8 has the configuration of a general computer system, including a CPU 81, a GPU 82, a ROM 83, a RAM 84, a fixed disk 85, a display 86, an input unit 87, a reader 88, a communication unit 89, and a bus 80.

[0039] The CPU 81 performs various arithmetic operations. The GPU 82 performs various arithmetic operations related to image processing. The ROM 83 stores the basic program. The RAM 84 stores various information. The fixed disk 85 stores information. The display 86 is a display unit that displays various information such as images. The input unit 87 includes a keyboard 87a and a mouse 87b that accept input from the operator. The reader 88 reads information from computer-readable recording media 881 such as optical disks, magnetic disks, magneto-optical disks, and memory cards. The display 86, keyboard 87a, mouse 87b, and reader 88 are connected to the bus 80 via an interface I / F. The communication unit 89 sends and receives signals to and from external devices of the control unit 8. The bus 80 is a signal circuit that connects the CPU 81, GPU 82, ROM 83, RAM 84, fixed disk 85, display 86, input unit 87, reader 88, and communication unit 89.

[0040] In the control unit 8, the program 882 is read in advance from the recording medium 881 via the reader 88 and stored in the fixed disk 85. The program 882 may also be stored in the fixed disk 85 via a network. The CPU 81 and GPU 82 perform arithmetic processing using the RAM 84 and fixed disk 85 according to the program 882. The CPU 81 and GPU 82 function as the arithmetic unit in the control unit 8. Other configurations besides the CPU 81 and GPU 82 that function as the arithmetic unit may also be employed.

[0041] In the substrate processing apparatus 1 shown in Figures 1 and 2, the control unit 8 performs calculation processing and the like according to the program 882, thereby realizing the information acquisition unit 801, which will be described later, as a functional configuration. All or part of this function may be realized by a dedicated electrical circuit. Alternatively, this function may be realized by multiple computers. The information acquisition unit 801 may be realized by a CPU 81, GPU 82, ROM 83, RAM 84, fixed disk 85 and their peripheral configurations. For example, the information acquisition unit 801 has a configuration that includes a calculation unit that performs calculation processing on the shape and position of the substrate 9 according to the program 882, and a storage unit that stores the information calculated by the calculation unit. Various storage elements (such as memory) can be used as the storage unit.

[0042] Figure 7 is a plan view showing an enlarged view of the area near the transport hand 121 and the containment container 7 of the indexer robot 12. Figure 8 is a side view showing the area near the transport hand 121 and the containment container 7. In Figures 7 and 8, the transport hand 121 located furthest to the (+Z) side of the multiple transport hands 121 is shown, and the other transport hands 121 are not shown. Also, in Figure 8, the light receiving device 621 on the (+Y) side, which will be described later, is not shown to facilitate understanding of the figure.

[0043] The transport hand 121 is a thin, plate-shaped member that is substantially perpendicular to the Z-direction and supports the substrate 9 from below. The transport hand 121 moves along the horizontal direction by a drive mechanism (not shown) provided on the base 122 (see Figures 1 and 2). In other words, the transport hand 121 is mounted on the indexer robot 12 so as to be able to move forward and backward, move up and down, and rotate.

[0044] The transport hand 121 is equipped with two claw portions 125 spaced apart from each other in the Y direction (i.e., left-right direction). The two claw portions 125 are located at approximately the same position in the Z direction. Each claw portion 125 is a roughly rectangular strip-shaped portion extending approximately parallel to the X direction (i.e., front-back direction). Each claw portion 125 is a substrate contact portion that directly contacts the lower surface of the substrate 9 (i.e., the main surface on the (-Z) side) from below the substrate 9 and supports the substrate 9. Alternatively, only a portion of each claw portion 125 may be in contact with the substrate 9, rather than the entire surface of each claw portion 125.

[0045] The substrate processing apparatus 1 further includes a light emitting unit 61 and a light receiving unit 62. The light receiving unit 62 includes one or more (two in the example shown in FIG. 7) light receiving devices 621. The light emitting unit 61 and the light receiving unit 62 are used to acquire information indicating the shape and position of a plurality of substrates 9 accommodated inside the accommodation container 7.

[0046] In the examples shown in FIGS. 7 and 8, the light emitting unit 61 and the light receiving unit 62 are fixed on the upper surface of the transfer hand 121 located on the most (+Z) side among the plurality of transfer hands 121 inside the index block 10. The light emitting unit 61 and the light receiving unit 62 fixed to the transfer hand 121 are moved in the Y direction and the Z direction together with the transfer hand 121 by the movement mechanism 124 (see FIGS. 1 and 2) of the index robot 12.

[0047] The light emitting unit 61 is disposed, for example, at the center in the Y direction of the transfer hand 121 on the (+X) side (i.e., the side far from the accommodation container 7) of the two claw portions 125 of the transfer hand 121. The light emitting unit 61 emits illumination light configured in a planar shape substantially perpendicular to the Z direction (i.e., the vertical direction) in the (-X) direction. In the present embodiment, the light emitting unit 61 includes a sheet laser light source 611 that emits sheet-shaped (i.e., planar) illumination light substantially perpendicular to the Z direction. The optical axis J1 of the sheet laser light source 611 extends in the (-X) direction substantially parallel to the XY plane. The cross-sectional shape of the sheet-shaped illumination light perpendicular to the optical axis J1 is a light beam that is substantially linear or substantially rectangular strip-shaped. The above illumination light may be visible light or invisible light such as short-wave infrared (SWIR). When the transfer hand 121 is in a state of facing the accommodation container 7 in the X direction, the light emitting unit 61 emits the above illumination light into the accommodation container 7 through the container opening 71 of the accommodation container 7.

[0048] The two light-receiving devices 621 are each arranged on the (+X) side of the two claw portions 125 of the transfer hand 121 at substantially the same position as the two claw portions 125 in the Y direction (i.e., the left-right direction). Specifically, each light-receiving device 621 is arranged on a virtual center line L3 that extends linearly in the X direction at the center in the left-right direction of the claw portion 125. The front principal point 622 of each light-receiving device 621 (i.e., the front principal point of the lens group provided in each light-receiving device 621) overlaps with the center line L3 in a plan view. The two light-receiving devices 621 are arranged substantially symmetrically with respect to the optical axis J1 of the light-emitting portion 61 in a plan view.

[0049] Figures 9 and 10 are diagrams depicting the illumination light 610 emitted from the sheet laser light source 611 of the light-emitting portion 61 in FIGS. 7 and 8. In FIG. 9, parallel oblique lines are added to the illumination light 610 for easy understanding of the figure. As shown in FIG. 10, the thickness of the illumination light 610 in the Z direction is smaller than the pitch P1 in the Z direction of a plurality of substrates 9 arranged in the Z direction in the housing container 7. The pitch P1 is the interval in the Z direction between two adjacent substrates 9 in the Z direction in a state where ideal substrates 9 without deformation such as curvature are housed in the housing container 7 up to the maximum number of housed sheets. Also, the pitch P1 is the interval in the Z direction between two adjacent internal support portions 72 (see FIG. 5) in the housing container 7 in the Z direction. The pitch P1 is, for example, 10 mm. The thickness of the illumination light 610 in the Z direction is preferably smaller than the thickness of an ideal substrate 9 without deformation such as curvature in the Z direction.

[0050] In the example shown in FIG. 9, the illumination light 610 emitted from the light-emitting portion 61 toward the housing container 7 gradually spreads in the Y direction (i.e., the left-right direction) as it approaches the housing container 7. At the position of the container opening 71 of the housing container 7, the width of the illumination light 610 in the Y direction is substantially the same as the width of the container opening 71 in the Y direction. Therefore, the illumination light 610 that has entered the interior of the housing container 7 from the container opening 71 is irradiated over substantially the entire width of the internal space 70 of the housing container 7. For this reason, at each position in the X direction within the housing container 7, the width of the illumination light 610 in the Y direction is larger than the width of the substrate 9 in the Y direction. In other words, in a plan view, substantially the entire substrate 9 is included in the illumination light 610.

[0051] The illumination light 610 that enters the interior of the containment container 7 is reflected by the inner surface 73 of the containment container 7. The inner surface 73 of the containment container 7 is substantially parallel to the Z direction, and the reflected light reflected by the inner surface 73 is directed toward the container opening 71 of the containment container 7 at approximately the same height as the illumination light 610 in the Z direction. The reflected light that spreads out to the outside of the containment container 7 through the container opening 71 is received by the two light receiving devices 621 of the light receiving unit 62.

[0052] Each light-receiving device 621 is, for example, an area camera capable of acquiring a planar image. The optical axis J2 of each light-receiving device 621 shown in Figure 7 is substantially parallel to the XY plane. The position of the optical axis J2 in the Z direction is substantially the same as the position of the illumination light 610 in the Z direction. In the example shown in Figure 7, the optical axis J2 is oriented in a direction inclined with respect to the X and Y directions. The optical axis J2 may, for example, be substantially parallel to the X direction (i.e., substantially parallel to the optical axis J1 of the sheet laser light source 611). The light-receiving device 621 images the inside of the containment container 7 in a planar shape substantially parallel to the Z direction and transmits the acquired image to the information acquisition unit 801 of the control unit 8 (see Figures 1 and 2). The information acquisition unit 801 acquires the shape of the reflected light of the illumination light 610 from the inner surface 73 of the containment container 7 based on the image sent from the two light-receiving devices 621.

[0053] As shown in Figures 9 and 10, when illumination light 610 is shone onto the inner surface 73 of the internal space 70 of the containment container 7 without being obstructed across the entire width of the internal space 70 (i.e., the entire length in the Y direction), the shape of the reflected light 610a of the illumination light 610 (i.e., reflected light from the inner surface 73) acquired by the information acquisition unit 801 is a straight line substantially perpendicular to the Z direction, as illustrated in Figure 11A. In Figure 11A, parallel diagonal lines are drawn in areas other than the reflected light 610a (i.e., dark areas), and the position of the substrate 9, which does not appear in the captured image, is indicated by a dashed line (the same applies to Figures 11B, 13A, and 13B described later). On the other hand, if a part of the illumination light 610 is obstructed by the substrate 9 which is curved in the vertical direction, the illumination light 610 shone on the substrate 9 is scattered and not received by the light receiving device 621. Therefore, the shape of the reflected light 610a of the illumination light 610 acquired by the information acquisition unit 801 is a shape in which a part of a straight line approximately perpendicular to the Z direction is interrupted, as illustrated in Figure 11B. Furthermore, if the entire illumination light 610 is blocked by the substrate 9, the information acquisition unit 801 does not acquire the shape of the reflected light 610a, and instead acquires information indicating that the reflected light 610a does not exist.

[0054] The information acquisition unit 801 acquires the shape of the reflected light based on a composite image obtained by combining, for example, the (+Y) half of the image captured by the (+Y) receiving device 621 and the (-Y) half of the image captured by the (-Y) receiving device 621. If the light reception intensity of a certain area in one of the two captured images is saturated, the pixel value of the corresponding area in the other captured image may be used as the pixel value of that area in the other captured image.

[0055] The method for acquiring the shape of reflected light by the information acquisition unit 801 is not limited to the above example and can be modified in various ways. For example, the information acquisition unit 801 may acquire the shape of the reflected light by first performing position correction based on the position of each light receiving device 621 on the two captured images acquired by the two light receiving devices 621, and then calculating the average of the pixel values ​​at each pixel of the two captured images. Alternatively, the information acquisition unit 801 may select one of the two captured images from which the shape of the reflected light is easier to acquire, and acquire the shape of the reflected light from that one captured image.

[0056] The shape of the reflected light acquired by the information acquisition unit 801 is stored in association with the position of the illumination light 610 in the Z direction when the captured image including the reflected light was acquired (i.e., the position of the reflected light in the Z direction). The position of the illumination light 610 in the Z direction is determined based on the position of the substrate support unit 120 (see Figures 9 and 10) in the Z direction when the captured image was acquired, and the mounting position of the light emission unit 61 on the substrate support unit 120.

[0057] In the substrate processing apparatus 1, the substrate support portion 120 moves in the Z direction by the movement mechanism 124 of the indexer robot 12, causing the light emitting portion 61, the illumination light 610 emitted from the light emitting portion 61, and the two light receiving devices 621 of the light receiving portion 62 to move relative to the containment container 7 in the Z direction. For example, the illumination light 610 and the light receiving portion 62 move at a constant speed in the (-Z) direction from a position facing the upper end of the container opening 71 in the X direction. In parallel with this movement of the illumination light 610 and the light receiving portion 62, the output continuously emitted from the light receiving portion 62 (i.e., multiple captured images continuously captured by the two light receiving devices 621) is sent to the information acquisition unit 801 (see Figures 1 and 2).

[0058] The information acquisition unit 801 acquires information on the shape and position of the multiple substrates 9 inside the containment container 7 as seen from the front view through the container opening 71 (i.e., the shape and position when viewed from the (+X) side parallel to the X direction towards the (-X) side) based on the shape and position in the Z direction of the reflected light acquired from the multiple captured images described above. In the following description, the information on the shape and position of the multiple substrates 9 inside the containment container 7 as seen from the front view will also be referred to as "container substrate information". The acquisition of container substrate information by the information acquisition unit 801 may be performed by various known methods. For example, container substrate information may be acquired by shifting the multiple captured images described above in the Z direction based on their respective imaging positions in the Z direction and superimposing them, and acquiring a composite image.

[0059] Figure 12 schematically illustrates the substrate information inside the container obtained by the information acquisition unit 801. In Figure 12, the area where the substrate 9 is present in a front view is shown with parallel diagonal lines as a dark area where the light receiving unit 62 could not receive reflected light from the inner surface 73 of the containment container 7, while the area where the substrate 9 is not present in a front view is shown without parallel diagonal lines as a bright area where reflected light from the inner surface 73 of the containment container 7 was received. Figure 12 corresponds to a composite image obtained by combining multiple captured images including reflected light, as shown in Figures 11A and 11B, taking into account the imaging position in the Z direction of each captured image.

[0060] In the substrate processing apparatus 1, the light emitting unit 61, the light receiving unit 62, the moving mechanism 124, and the information acquisition unit 801 constitute a substrate information acquisition apparatus 60 that acquires information on the shape and position of a plurality of substrates 9 arranged in the Z direction (i.e., vertical direction) inside the containment container 7 (i.e., substrate information inside the container).

[0061] In the substrate processing apparatus 1, before the substrate 9 in the storage container 7 is removed by the indexer robot 12, the substrate information acquisition device 60 acquires the substrate information inside the container. Based on the substrate information inside the container, the control unit 8 (see Figure 1) determines the insertion position of the transport hand 121 into the storage container 7 and the removal operation of the transport hand 121 after supporting the substrate 9.

[0062] Specifically, the insertion position for the two claws 125 of the transport hand 121 is determined to be a position below the substrate 9 to be transported, where the substrate 9 is not visible in a front view. Furthermore, based on the shape and position of the substrate 9 to be transported and the substrate 9 adjacent to it on the (+Z) side in a front view, the shortest distance in the Z direction between these two substrates 9 in a front view is determined. The transport hand 121's transport operation is then determined so that the lifting distance of the transport hand 121 after supporting the substrate 9 to be transported is less than this shortest distance. If this shortest distance is less than the lower limit of the lifting distance required to transport the substrate 9, the substrate 9 is deemed untransportable.

[0063] In the substrate processing apparatus 1, the illumination light 610 emitted from the light emission unit 61 does not necessarily have to be in the form of a sheet substantially perpendicular to the Z direction, but may be configured as a plane substantially perpendicular to the Z direction. For example, multiple light beams, each extending substantially linearly in the X direction, may be arranged in the Y direction to form illumination light configured as a plane substantially perpendicular to the Z direction. In this case, on the inner surface 73 of the containment container 7 irradiated with the illumination light, multiple point-shaped beam spots will be aligned in the Y direction. The same applies to the image captured by the light receiving device 621. It is preferable that these multiple beam spots are arranged at equal intervals with respect to the Y direction. Alternatively, illumination light configured as a plane substantially perpendicular to the Z direction may be realized by scanning a single light beam extending substantially linearly in the X direction in the Y direction.

[0064] As described above, the substrate information acquisition device 60 is a device that acquires information on the shape and position of a plurality of substrates 9 arranged vertically (i.e., in the Z direction) inside the containment container 7. The substrate information acquisition device 60 comprises a light emitting unit 61, a light receiving unit 62, a moving mechanism 124, and an information acquisition unit 801. The light emitting unit 61 emits illumination light 610, which is configured as a planar shape perpendicular to the vertical direction, into the containment container 7 through a container opening 71 provided on the front side (i.e., the (+X) side) of the containment container 7. The vertical thickness of the illumination light 610 is smaller than the vertical pitch P1 of the plurality of substrates 9. The light receiving unit 62 receives reflected light reflected from the inner surface 73 of the containment container 7. The light receiving unit 62 has the same optical axis J2 as the illumination light 610 in the vertical direction. The moving mechanism 124 moves the illumination light 610 and the light receiving unit 62 relative to the containment container 7 in the vertical direction. The information acquisition unit 801 acquires information on the shape and position of multiple substrates 9 based on the output continuously emitted from the light receiving unit 62 in parallel with the relative movement of the illumination light 610 by the moving mechanism 124 and the light receiving unit 62.

[0065] In this way, the substrate information acquisition device 60 irradiates the inside of the containment container 7 with illumination light 610 configured as a planar shape thinner than the pitch P1 between the substrates 9. This prevents the illumination light 610 irradiated onto the area where a substrate 9 exists in a front view (i.e., when viewed from the (+X) side parallel to the X direction towards the (-X) side) from being reflected by the substrate 9 and the substrate 9 adjacent to it, and from being incident on the light receiving unit 62 against the intention. It also prevents the illumination light 610 irradiated onto an area where no substrate 9 exists in a front view from being reflected and scattered by a substrate 9 located above or below that area. As a result, the shape and position of the substrate 9 at the back of the containment container 7 (i.e., the (-X) side) can be acquired with high accuracy.

[0066] As described above, it is preferable that the light emission unit 61 includes a sheet laser light source 611 that emits a sheet-shaped illumination light 610. This makes it easy to form a planar illumination light 610 in the substrate information acquisition device 60.

[0067] As described above, it is preferable that the thickness of the illumination light 610 in the vertical direction is thinner than the thickness of the substrate 9 in the vertical direction. This allows the inside of the containment container 7 to be divided into smaller sections in the vertical direction and imaged. As a result, information on the shape and position of the multiple substrates 9 in the front view inside the containment container 7 can be acquired with even greater accuracy.

[0068] As described above, it is preferable that the width of the illumination light 610 in the left-right direction (i.e., the Y direction) is greater than the width of the substrate 9 in the left-right direction at each position in the front-back direction (i.e., the X direction). This allows for accurate acquisition of shape and position information of each substrate 9 in a front view across the entire width of each substrate 9 in the left-right direction. As a result, when the substrate processing apparatus 1 lifts a substrate 9 that is curved to be convex upward, for example, with the transport hand 121, it is possible to accurately determine whether the substrate 9 will collide with another substrate 9 adjacent to it above.

[0069] The substrate processing apparatus 1 comprises the substrate information acquisition apparatus 60 described above, an indexer block 10, and a processing block 20. The indexer block 10 houses a first transport robot (i.e., an indexer robot 12) that loads and unloads substrates 9 into and out of the storage container 7. The processing block 20 houses a processing unit 21 that processes the substrates 9 and a second transport robot (i.e., a center robot 22) that loads and unloads substrates 9 into and out of the processing unit 21. The light emission unit 61, light receiving unit 62, and moving mechanism 124 of the substrate information acquisition apparatus 60 are located in the indexer block 10.

[0070] This allows the substrate processing apparatus 1 to accurately acquire information about the substrate inside the container. As a result, when unloading the substrate 9 from the container 7, the insertion position of the transport hand 121 into the container 7 can be accurately determined. Furthermore, the unloading operation of the transport hand 121 after supporting the substrate 9 (for example, the lifting distance of the transport hand 121, or whether or not unloading is possible) can be accurately determined.

[0071] As described above, in the substrate processing apparatus 1, it is preferable that the light emitting section 61 and the light receiving section 62 of the substrate information acquisition device 60 are fixed to the substrate support section 120 that supports the substrate 9 in the indexer robot 12. Furthermore, it is preferable that the moving mechanism 124 of the substrate information acquisition device 60 moves the substrate support section 120 in the vertical direction in the indexer robot 12.

[0072] In this way, by fixing the relative positions of the light-emitting unit 61 and the light-receiving unit 62 and the transport hand 121 used for unloading the substrate 9, the insertion position of the transport hand 121 into the storage container 7 and the unloading operation of the transport hand 121 after supporting the substrate 9 can be determined with even greater precision. Furthermore, by using the movement mechanism 124 of the indexer robot 12 as the movement mechanism of the substrate information acquisition device 60, the structure of the substrate processing device 1 can be simplified while accurately acquiring substrate information inside the container.

[0073] In the above example, the substrate support portion 120 includes a substrate contact portion (i.e., claw portion 125) that extends in the front-to-back direction (i.e., the X direction) below the substrate 9 and directly contacts the lower surface of the substrate 9 to support the substrate 9. Preferably, the front principal point of the light receiving portion 62 (i.e., the front principal point 622 of each light receiving device 621) coincides in a plan view with the center line L3 that extends linearly in the front-to-back direction at the center of the claw portion 125 in the left-to-right direction (i.e., the Y direction). This makes it possible to accurately acquire the shape and position of multiple substrates 9 on the extension of the claw portion 125 in the X direction, even when the optical axis J2 of the light receiving device 621 is oriented in a direction inclined with respect to the center line L3 of the claw portion 125. As a result, the insertion position of the transport hand 121 into the storage container 7 can be determined with even greater accuracy.

[0074] In the above example, the substrate support portion 120 comprises a plurality of substrate contact portions (i.e., a plurality of claw portions 125) that each extend in the front-to-back direction (i.e., the X direction) below the substrate 9 and directly contact the lower surface of the substrate 9 to support the substrate 9. Preferably, the light receiving portion 62 comprises a plurality of claw portions 125 and a plurality of light receiving devices 621 that are respectively arranged at the same positions in the left-to-right direction (i.e., the Y direction). This makes it possible to accurately acquire the shape and position of the plurality of substrates 9 along the extension line in the X direction of each claw portion 125. As a result, the insertion position of the transport hand 121 into the storage container 7 can be determined with even greater accuracy.

[0075] In the above example, the substrate information inside the container is obtained by combining the entirety of multiple captured images, as shown in Figures 11A and 11B, taking into account the imaging position of each image in the Z direction. However, the method of obtaining the substrate information inside the container is not limited to this. For example, in the above multiple captured images, as shown enclosed by the dashed line in Figures 13A and 13B, only the central part in the Z direction of each captured image is extracted as an ROI (Region of Interest) and output to the information acquisition unit 801. By arranging only this central part of each captured image in the Z direction, taking into account the imaging position of each image in the Z direction, the substrate information inside the container, as shown in Figure 12, can be obtained. The central part in the Z direction of the captured image mentioned above means the region in the captured image that corresponds to the vicinity of the optical axis J2 of the light-receiving device 621 with respect to the Z direction. If the captured image contains reflected light 610a, the reflected light 610a is included in the central part. In other words, an image of the range corresponding to the vicinity of the optical axis J2 of the light-receiving device 621 can be extracted.

[0076] In this way, in the multiple images continuously captured by the light-receiving device 621 in parallel with the relative movement of the illumination light 610 and the light-receiving unit 62 with respect to the housing container 7, only the central part in the Z direction of each captured image is output to the information acquisition unit 801, thereby improving the frame rate and image quality of the images output to the information acquisition unit 801. As a result, information on the shape and position of the multiple substrates 9 in a front view within the housing container 7 can be acquired with even greater accuracy.

[0077] Furthermore, in the above-mentioned multiple captured images, the size of the central portion in the Z direction output to the information acquisition unit 801 from each captured image may be slightly increased, and the central portion may be shifted in the Z direction based on the respective imaging positions in the Z direction, superimposed, and averaged to acquire a composite image (i.e., the composite image is acquired using the TDI (Time Delay Integration) method) to acquire information on the substrates inside the container. This reduces the influence of noise on the composite image. As a result, information on the shape and position of the multiple substrates 9 in a front view inside the containment container 7 can be acquired with even greater accuracy.

[0078] Various modifications are possible to the above-described substrate information acquisition device 60 and substrate processing device 1.

[0079] For example, in the substrate processing apparatus 1, the front principal point 622 of the light receiving device 621 does not necessarily have to coincide with the center line L3 of the claw portion 125 in a plan view, and may be positioned at a location offset from the center line L3.

[0080] Furthermore, the shape of the transport hand 121 in the substrate processing apparatus 1 can be changed in various ways. For example, a transport hand equipped with only one claw portion 125 may be used in the substrate support portion 120 of the indexer robot 12. In this case, for example, there is one light-receiving device 621 provided in the light-receiving portion 62, and the sheet laser light source 611 and the light-receiving device 621 are arranged side by side near the center line L3 of the single claw portion 125.

[0081] The width in the Y direction of the illumination light 610 irradiated from the light emission unit 61 into the containment container 7 does not necessarily have to be greater than the width of the substrate 9 in the Y direction; it may be less than or equal to the width of the substrate 9 in the Y direction.

[0082] The thickness of the illumination light 610 in the Z direction may be greater than or equal to the thickness of the substrate 9 in the Z direction.

[0083] The light-emitting unit 61 and the light-receiving unit 62 do not necessarily have to be fixed to the transport hand 121 on the (+Z) side, but may be fixed to any part of the substrate support unit 120 of the indexer robot 12. For example, the light-emitting unit 61 and the light-receiving unit 62 may be fixed to the transport hand 121 on the (-Z) side among the multiple transport hands 121. Also, in the substrate processing apparatus 1, the number of light-emitting units 61 and the number of light-receiving devices 621 in the light-receiving unit 62 may be changed in various ways. For example, the sheet laser light source 611 may be placed next to each light-receiving device 621.

[0084] The light-emitting unit 61 and the light-receiving unit 62 may be provided independently of the indexer robot 12. For example, the substrate information acquisition device 60b shown in Figure 14 comprises an information acquisition head 65, a moving mechanism 66, and the above-mentioned information acquisition unit 801 (see Figure 1). The information acquisition head 65 is a member that integrally holds the above-mentioned light-emitting unit 61 and light-receiving unit 62 and the mirror 67. The information acquisition head 65 is provided inside the indexer block 10 and is located between the plurality of housing containers 7 and the indexer robot 12 in the X direction.

[0085] In the information acquisition head 65, the mirror 67 is positioned on the (-Z) side of the light emission unit 61 and the light receiving unit 62. Illumination light 610b emitted from the light emission unit 61 in the (-Z) direction is reflected by the mirror 67 and directed toward the container opening 71 of the containment container 7. The illumination light 610b that enters the interior of the containment container 7 through the container opening 71 is, like the illumination light 610 described above, light configured in a planar shape perpendicular to the Z direction, and the thickness of the illumination light 610b in the Z direction is smaller than the pitch P1 described above. The reflected light reflected by the inner surface 73 inside the containment container 7 is guided toward the (+Z) direction via the mirror 67 and received by the light receiving unit 62.

[0086] The moving mechanism 66 moves the information acquisition head 65 in the Y and Z directions. The movement of the information acquisition head 65 by the moving mechanism 66 is performed independently of the movement of the substrate support part 120 by the moving mechanism 124 of the indexer robot 12. In the substrate information acquisition device 60b, by moving the information acquisition head 65 in the Z direction by the moving mechanism 66, the illumination light 610b and the light receiving unit 62 move relative to the containment container 7 in the vertical direction. Then, in parallel with the relative movement of the illumination light 610b and the light receiving unit 62 by the moving mechanism 66, the captured image acquired by the light receiving unit 62 is continuously output to the information acquisition unit 801, and the information acquisition unit 801 acquires information on the shape and position of the multiple substrates 9 inside the containment container 7 (i.e., substrate information inside the container). Note that it is also possible to omit the mirror 67 from the configuration of the substrate information acquisition device 60b shown in Figure 14. If the size of the light-emitting section 61 and the light-receiving section 62 is small enough not to hinder the operation of the indexer robot 12, it is possible to directly illuminate the substrate 9 from the (+X) side of the substrate 9 with the light-emitting section 61.

[0087] The substrate information acquisition devices 60 and 60b may be provided in a device different from the substrate processing device 1. For example, the light emitting unit 61 and the light receiving unit 62 may be provided in each load port 11. Specifically, in the load port 11, the light emitting unit 61 and the light receiving unit 62 may be attached to a door opening / closing mechanism that moves the door of the containment container 7 (i.e., the door covering the container opening 71) in the vertical direction to open and close it.

[0088] In the substrate information acquisition devices 60 and 60b, for example, a moving mechanism is provided to move the containment container 7 in the Z direction, and as the containment container 7 moves in the Z direction while the light emitting unit 61 and the light receiving unit 62 are stationary, the illumination light 610, 610b and the light receiving unit 62 may move relative to the containment container 7 in the Z direction.

[0089] The light-receiving unit 62 does not necessarily need to be equipped with an area camera; it may be equipped with a line camera. The line camera may be a TDI line scan camera.

[0090] The substrate processing apparatus 1 described above may be used to process glass substrates used in flat panel displays such as liquid crystal displays or organic electroluminescence (EL) displays, or glass substrates used in other displays, in addition to semiconductor substrates. Furthermore, the substrate processing apparatus 1 described above may be used to process substrates for optical discs, magnetic discs, magneto-optical discs, photomasks, ceramic substrates, and solar cell substrates.

[0091] The configurations in the above embodiments and each modified example may be combined as appropriate, as long as they do not contradict each other.

[0092] Although the invention has been described in detail, the above description is illustrative and not limiting. Therefore, it can be said that numerous modifications and embodiments are possible as long as they do not deviate from the scope of the present invention.

[0093] 1 Substrate processing device 7 Containing container 9 Substrate 10 Indexer block 12 Indexer robot 20 Processing block 21 Processing unit 22 Center robot 60, 60b Substrate information acquisition device 61 Light emission unit 62 Light receiving unit 66 Moving mechanism 71 Container opening 73 Inner surface 120 Substrate support unit 121 Transport hand 124 Moving mechanism 125 Claw unit 610, 610b Illumination light 610a Reflected light 611 Sheet laser light source 621 Light receiving device 622 Front principal point 801 Information acquisition unit J1, J2 Optical axis L3 Centerline P1 Pitch

Claims

1. A substrate information acquisition device for acquiring information on the shape and position of a plurality of substrates arranged vertically inside a containment container, comprising: a light emission unit that emits illumination light, which is configured as a vertically perpendicular planar shape and has a vertical thickness smaller than the vertical pitch of the plurality of substrates, toward the inside of the containment container through a container opening provided on the front side surface of the containment container; a light receiving unit that has the same optical axis as the illumination light in the vertical direction and receives reflected light reflected from the inner surface of the containment container; a movement mechanism that moves the illumination light and the light receiving unit relative to the containment container in the vertical direction; and an information acquisition unit that acquires information on the shape and position of the plurality of substrates based on an output continuously output from the light receiving unit in parallel with the relative movement of the illumination light and the light receiving unit by the movement mechanism.

2. A substrate information acquisition apparatus according to claim 1, wherein the light emission unit comprises a sheet laser light source that emits the sheet-shaped illumination light.

3. A substrate information acquisition device according to claim 1, wherein the thickness of the illumination light in the vertical direction is thinner than the thickness of the substrate in the vertical direction.

4. A substrate information acquisition device according to claim 1, wherein the width of the illumination light in the left-right direction is greater than the width of the substrate in the left-right direction at each position in the front-rear direction.

5. A substrate information acquisition device according to claim 1, wherein the light receiving unit comprises an area camera that captures a planar image of the inside of the containment container, and in a plurality of captured images continuously captured by the area camera in parallel with the illumination light and the relative movement of the light receiving unit, only the central part in the vertical direction of each captured image is output to the information acquisition unit.

6. A substrate processing apparatus for processing substrates, comprising: a substrate information acquisition device according to any one of claims 1 to 5; an indexer block on which a first transport robot for loading and unloading substrates into and out of the storage container is disposed; and a processing unit for processing substrates and a processing block on which a second transport robot for loading and unloading substrates into and out of the processing unit is disposed, wherein the light emission unit, the light receiving unit and the moving mechanism of the substrate information acquisition device are disposed in the indexer block.

7. A substrate processing apparatus according to claim 6, wherein the light emitting unit and the light receiving unit of the substrate information acquisition apparatus are fixed to a substrate support unit that supports the substrate in the first transport robot, and the moving mechanism of the substrate information acquisition apparatus moves the substrate support unit in the vertical direction in the first transport robot.

8. A substrate processing apparatus according to claim 7, wherein the substrate support portion includes a substrate contact portion that extends in the front-rear direction below the substrate and directly contacts the lower surface of the substrate to support the substrate, and the front principal point of the light receiving portion coincides in a plan view with a center line that extends linearly in the front-rear direction at the center of the left-right direction of the substrate contact portion.

9. A substrate processing apparatus according to claim 7, wherein the substrate support portion comprises a plurality of substrate contact portions, each extending in the front-rear direction below the substrate and directly contacting the lower surface of the substrate to support the substrate, and the light receiving portion comprises a plurality of light receiving devices, each arranged at the same position in the left-right direction as the plurality of substrate contact portions.

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