Substrate transport apparatus and substrate transport method

Abstract

This technology helps to avoid collisions between the tip of the end effector and the circuit board. [Solution] The substrate transport device 110 includes a transport unit 20 and a sensor 30. The transport unit 20 includes an end effector 21, and the end effector 21 is inserted into the substrate container C from its tip to transport substrates to and from the substrate container C. The sensor 30 includes a light-emitting unit 31 that outputs measurement light L1 toward the tip of the end effector 21 located immediately before it enters the substrate container C, and a light-receiving unit 32 that receives the measurement light L1 from the light-emitting unit 31, and detects the position of the tip of the end effector 21 based on the measurement light L1 received by the light-receiving unit 32.

Description

Technical Field

[0001] The present disclosure relates to a substrate transfer device and a substrate transfer method.

Background Art

[0002] Conventionally, a substrate transfer device for transferring a substrate has been used (for example, Patent Document 1). In Patent Document 1, the substrate transfer device includes an end effector, an arm, an effector sensor, and an arm sensor. A substrate is placed on the end effector. The tip of the arm is connected to the base end of the end effector. When the arm is displaced in the horizontal direction, the end effector moves horizontally. Also, when the arm moves up and down, the end effector also moves up and down.

[0003] When the end effector lifts the substrate, the end effector vibrates due to hitting the substrate.

[0004] The effector sensor detects the height position of a portion of the end effector closer to the connection portion with the arm than the portion where the substrate is placed. The arm sensor detects the height position of the arm. In Patent Document 1, the difference between the detection value of the effector sensor and the detection value of the arm sensor is calculated. The vibration of the end effector appears as the amplitude of this difference.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] In some cases, a transport unit may need to retrieve a circuit board from a circuit board holder containing multiple boards. In this case, the transport unit first inserts its end effector into the circuit board holder, taking care not to collide with any of the boards inside. Then, the transport unit receives the board from the circuit board holder with the end effector and retracts the end effector from the circuit board holder. This allows the transport unit to retrieve the board from the circuit board holder.

[0007] If the end effector vibrates just before entering the board housing, there is a risk that the end effector may collide with the board when it enters the housing. Similarly, if the height of the end effector's tip just before entry is off from the desired position, there is a risk that the end effector may collide with the board.

[0008] As described in Patent Document 1, the height position of the end effector can be confirmed by detecting the height position of the end effector using an effector sensor. However, in Patent Document 1, the effector sensor detects the height position of the part of the end effector that is closer to the connection point with the arm than the part on which the substrate is placed. As a result, the detection accuracy of the position of the tip of the end effector is low. Consequently, it is not possible to avoid collisions between the tip of the end effector and the substrate with high accuracy when inserting the end effector into the substrate housing.

[0009] Therefore, this disclosure aims to provide a technology that contributes to avoiding collisions between the tip of an end effector and a substrate. [Means for solving the problem]

[0010] The substrate transport device includes an end effector, a transport unit that moves the end effector into the substrate container from its tip, and transports substrates to and from the substrate container, a light-emitting unit that outputs measurement light toward the tip of the end effector located immediately before it enters the substrate container, and a light-receiving unit that receives the measurement light from the light-emitting unit, and a sensor that detects the position of the tip of the end effector based on the measurement light received by the light-receiving unit.

[0011] The substrate transport method comprises the steps of moving the end effector of the transport unit toward a substrate container containing a substrate, and emitting a measurement light from a light-emitting unit toward the tip of the end effector located immediately in front of the substrate container, and detecting the position of the tip based on the measurement light received by the light-receiving unit. [Effects of the Invention]

[0012] The substrate transport device and substrate transport method contribute to avoiding collisions between the tip of the end effector and the substrate. [Brief explanation of the drawing]

[0013] [Figure 1] This is a schematic plan view showing an example of the configuration of a substrate processing apparatus including a substrate transport device according to the first embodiment. [Figure 2] This is a block diagram that schematically shows an example of the internal configuration of the control unit. [Figure 3] This is a schematic front view showing an example of the configuration of a circuit board housing. [Figure 4] This diagram schematically shows an example of the configuration of the first transport unit. [Figure 5] This is a schematic perspective view showing an example of how the first transport unit removes a circuit board. [Figure 6] This is a schematic plan view illustrating an example of how the first transport unit removes a circuit board. [Figure 7]It is a diagram schematically showing an example of the positional relationship among an end effector, a light receiving part, and measurement light. [Figure 8] It is a flowchart showing an example of the operation of a substrate transfer device. [Figure 9] It is a perspective view schematically showing a first example of a part of the configuration of a substrate transfer device according to the second embodiment. [Figure 10] It is a perspective view schematically showing a first example of a part of the configuration of a substrate transfer device according to the second embodiment. [Figure 11] It is a perspective view schematically showing a second example of a part of the configuration of a substrate transfer device according to the second embodiment. [Figure 12] It is a diagram schematically showing an example of the positional relationship among a first light emitting part, a first light receiving part, and a first tip part of a first long part. [Figure 13] It is a perspective view schematically showing a third example of a part of the configuration of a substrate transfer device according to the second embodiment. [Figure 14] It is a diagram schematically showing an example of the positional relationship between a first light emitting and receiving part and a substrate storage container. [Figure 15] It is a perspective view schematically showing a fourth example of a part of the configuration of a substrate transfer device according to the second embodiment. [Figure 16] It is a perspective view schematically showing a fifth example of a part of the configuration of a substrate transfer device according to the second embodiment. [Figure 17] It is a perspective view schematically showing a sixth example of a part of the configuration of a substrate transfer device according to the second embodiment. [Figure 18] It is a perspective view schematically showing a seventh example of a part of the configuration of a substrate transfer device according to the second embodiment. [Figure 19] It is a perspective view schematically showing a seventh example of a part of the configuration of a substrate transfer device according to the second embodiment.

Embodiments for Carrying Out the Invention

[0014] The embodiments will be described in detail below with reference to the drawings. Note that, for the purpose of ease of understanding, the dimensions and number of parts in the drawings are exaggerated or simplified as needed. Also, parts with similar configurations and functions are denoted by the same reference numerals, and redundant explanations are omitted in the following description.

[0015] Furthermore, in the following explanations, similar components will be denoted by the same symbols, and their names and functions will also be the same. Therefore, detailed explanations of them may be omitted to avoid redundancy.

[0016] Furthermore, even if ordinal numbers such as "first" or "second" are used in the following descriptions, these terms are used for convenience to facilitate understanding of the embodiments and are not limited to the order that may result from these ordinal numbers.

[0017] When expressions indicating relative or absolute positional relationships are used (e.g., "in one direction," "along one direction," "parallel," "orthogonal," "center," "concentric," "coaxial," etc.), unless otherwise specified, such expressions shall not only strictly represent the positional relationship but also represent a state in which there is a relative displacement in terms of angle or distance within a tolerance or a range in which equivalent functionality is obtained. When expressions indicating equality are used (e.g., "identical," "equal," "homogeneous," etc.), unless otherwise specified, such expressions shall not only strictly represent a state in which there is a quantitatively exact equality but also represent a state in which there is a difference within a tolerance or a range in which equivalent functionality is obtained. When expressions indicating shape are used (e.g., "quadrilateral" or "cylindrical"), unless otherwise specified, such expressions shall not only strictly represent the geometrically exact shape but also represent a shape with features such as concavities or chamfers within a range in which equivalent effects are obtained. When expressions such as "possess," "equip," "include," or "have" a single component are used, such expressions are not exclusive expressions that exclude the existence of other components. When the expression "at least one of A, B, and C" is used, it includes A only, B only, C only, any two of A, B, and C, and all of A, B, and C.

[0018] <First Embodiment> <Overall configuration of the substrate processing equipment> Figure 1 is a schematic plan view showing an example of the configuration of a substrate processing apparatus 100 including a substrate transport device 110 according to the first embodiment. The substrate processing apparatus 100 is a single-wafer processing apparatus that processes substrates W one at a time.

[0019] The substrate W is, for example, a semiconductor wafer, a substrate for liquid crystal displays, an organic electroluminescence (EL) substrate, a flat panel display (FPD) substrate, an optical display substrate, a magnetic disk substrate, an optical disk substrate, a magneto-optical disk substrate, a photomask substrate, or a solar cell substrate. The substrate W has a thin, flat shape. In the following, it is assumed that the substrate W is a semiconductor wafer. The substrate W has, for example, a disc shape. The diameter of the substrate W is, for example, about 300 mm, and the film thickness of the substrate W is, for example, about 0.5 mm or more and about 3 mm or less.

[0020] In the example shown in Figure 1, the substrate processing apparatus 100 includes a substrate transport device 110, a processing block 120, and a control unit 90. The processing block 120 is primarily responsible for processing the substrate W. In the example shown in Figure 1, the substrate transport device 110 is primarily responsible for transporting the substrate W between the outside of the substrate processing apparatus 100 and the processing block 120. The substrate transport device 110 may also be called an indexer.

[0021] The substrate transport device 110 includes a first transport unit 20 and a sensor 30. As shown in Figure 1, the substrate transport device 110 may be provided with a load port 10. A substrate container C brought in from the outside is placed on the load port 10. In other words, the load port 10 includes a mounting platform on which the substrate container C is placed. The mounting platform may be provided with a holding mechanism (not shown) for holding the substrate container C. In the example in Figure 1, a plurality of load ports 10 are arranged along a horizontal arrangement direction Dy. A plurality of substrates W are housed in the substrate container C. As an example, the plurality of substrates W are housed in the substrate container C with spacing between them in the vertical direction. A specific example of the configuration of the substrate container C will be described in detail later.

[0022] The first transport unit 20 is a transport robot, and may also be called an indexer robot. The first transport unit 20 transports the substrates W between each substrate container C and the processing block 120. As shown in Figure 1, the first transport unit 20 includes an end effector 21, which may also be called a hand. The first transport unit 20 inserts the end effector 21 into the substrate container C from its tip to take the substrates W out of the substrate container C or to pass the substrates W to the substrate container C.

[0023] In the example shown in Figure 1, the first transport unit 20 is provided to be movable along the arrangement direction Dy and can be stopped at a position facing each substrate container C. With the first transport unit 20 facing the substrate container C, it moves the end effector 21 toward the inside of the substrate container C from its tip and stops the end effector 21 directly beneath the substrate W. Then, the first transport unit 20 raises the end effector 21 to lift the unprocessed substrate W and retracts the end effector 21 supporting the substrate W from the substrate container C. This allows the first transport unit 20 to remove the substrate W from the substrate container C.

[0024] Next, the first transport unit 20 moves along the array direction Dy toward a position where it can transfer the substrate W to the processing block 120, and at that position, it transfers the substrate W to the processing block 120. The processing block 120 processes the substrate W. Then, the first transport unit 20 receives the processed substrate W from the processing block 120. Having received the processed substrate W, the first transport unit 20 moves to a position facing the substrate container C. The first transport unit 20 moves the end effector 21 supporting the substrate W into the substrate container C, and then lowers the end effector 21. As a result, the processed substrate W is transferred from the end effector 21 to the substrate container C. Then, the first transport unit 20 retracts the end effector 21. In this manner, the first transport unit 20 transports the substrate W between each substrate container C and the processing block 120.

[0025] Sensor 30 detects the position of the tip of the end effector 21, which is located directly in front of the substrate housing C. In the example shown in Figure 1, sensor 30 is provided in a one-to-one relationship with the substrate housing C. A specific example of sensor 30 will be described in detail later.

[0026] In the example shown in Figure 1, the processing block 120 includes a plurality of processing units 121 and a second transport unit 122. The second transport unit 122 is a transport robot that transports the substrate W between the first transport unit 20 and the plurality of processing units 121. In the example shown in Figure 1, the second transport unit 122 transfers the substrate W from the first transport unit 20 via a relay unit 123. The relay unit 123 may be a shelf on which the substrate W is placed, or it may be a shuttle-type transport unit.

[0027] In the example shown in Figure 1, multiple (e.g., four) processing units 121 are arranged to surround the second transport unit 122 in a plan view. This second transport unit 122 may also be called a center robot. At each position in the plan view, the multiple processing units 121 may be stacked vertically. That is, multiple (four in the figure) towers TW, each composed of multiple processing units 121 stacked vertically, may be arranged to surround the second transport unit 122. The processing units 121 perform various wet or dry processing on the substrate W, for example.

[0028] The control unit 90 comprehensively controls the substrate processing apparatus 100. More specifically, the control unit 90 controls the first transport unit 20, the sensor 30, the second transport unit 122, and the processing unit 121. Figure 2 is a schematic block diagram showing an example of the internal configuration of the control unit 90. The control unit 90 is an electronic circuit and includes, for example, a data processing unit 91 and a storage unit 92. The data processing unit 91 and the storage unit 92 may be interconnected via a bus 93. The data processing unit 91 may be an arithmetic processing unit such as a CPU (Central Processor Unit). The storage unit 92 may include a non-temporary storage unit (e.g., ROM (Read Only Memory)) 921 and a temporary storage unit (e.g., RAM (Random Access Memory)) 922. The non-temporary storage unit 921 may store, for example, a program that defines the processing to be executed by the control unit 90. By executing this program, the data processing unit 91 enables the control unit 90 to execute the processing defined in the program. Of course, some or all of the processing performed by the control unit 90 may be performed by hardware such as dedicated logic circuits.

[0029] In the example shown in Figure 2, the control unit 90 is also connected to a non-temporary storage unit 94 (for example, a memory such as flash memory or a hard disk). In the example shown in Figure 2, reference data D1 is stored in the storage unit 94. Reference data D1 will be described in detail later.

[0030] <Circuit board housing C> The substrate housing C may be a FOUP (Front Opening Unified Pod) or SMIF (Standard Mechanical Interface) pod that houses the substrate W in a sealed state, or it may be an OC (Open Cassette) that houses the substrate W in an open state. The substrate housing C may also be called a carrier.

[0031] Figure 3 is a schematic front view showing an example of the configuration of a substrate housing C. The substrate housing C has a box-shaped form that opens in one direction, approximately horizontally (towards the front of the paper in Figure 3). Specifically, the substrate housing C has a bottom 51, a top 52, and side walls 53. The bottom 51 and top 52 have a rectangular plate shape and face each other with a gap between them in the vertical direction. The side walls 53 connect the periphery of the bottom 51 and the periphery of the top 52 on three sides. As a result, an opening 55 is formed in the part where the side walls 53 are not provided. The substrate W is removed from or loaded into the substrate housing C through the opening 55. The substrate housing C may be provided with a lid that can be opened and closed to close the opening 55.

[0032] The substrate housing C is positioned in the load port 10 such that its opening 55 faces the first transport unit 20 (see also Figure 1). Multiple projection support parts 54 are provided on the inner surface of the side wall 53 to support the lower surface of the substrate W. Each projection support part 54 protrudes inward from the inner surface of the side wall 53. The upper surface of the projection support part 54 is approximately horizontal. Each projection support part 54 supports the end of the substrate W. Multiple projection support parts 54 are provided at intervals in the vertical direction, and multiple substrates W are supported by the projection support parts 54 on the left and right sides of the paper. Multiple substrates W are housed in the substrate housing C in a stacked state with gaps in the vertical direction. The number of substrates W housed in the substrate housing C is arbitrary, for example, 25.

[0033] Since both ends of the substrate W are supported inside the substrate housing C, the substrate W may bend, as shown in Figure 3, especially if the substrate W is thin. Specifically, the substrate W may bend in a convex shape downwards. In this case, the distance between adjacent substrates W becomes narrower in the central part of the substrate W. Since the end effector 21 of the first transport unit 20 enters between adjacent substrates W, a narrower distance increases the risk of the end effector 21 colliding with the substrate W.

[0034] In this embodiment, the sensor 30 detects the position of the tip of the end effector 21. Below, the configuration of the first transport unit 20 will be described in detail, followed by a detailed description of the sensor 30.

[0035] <First transport unit> Figure 4 is a schematic diagram showing an example of the configuration of the first transport unit 20. The first transport unit 20 includes an end effector 21 and a transport drive unit 22. A substrate W is placed on the end effector 21. The end effector 21 supports the substrate W. In the examples of Figures 1 and 4, the end effector 21 has a plate-like shape and is installed in a position where its thickness direction is aligned with the vertical direction. In the examples of Figures 1 and 4, the end effector 21 includes a first elongated portion 211A, a second elongated portion 211B, and a connecting portion 212. The first elongated portion 211A has an elongated plate-like shape and is installed in a position where its longitudinal direction is aligned with the horizontal direction. The second elongated portion 211B has an elongated plate-like shape and is installed in a position where its longitudinal direction is aligned with the horizontal direction. The height positions of the first elongated portion 211A and the second elongated portion 211B are approximately the same. The first elongated portion 211A and the second elongated portion 211B are spaced apart in their short-side directions. The connecting portion 212 connects the base end of the first elongated portion 211A and the base end of the second elongated portion 211B to each other. The connecting portion 212 has a plate-like shape and is provided in a position where its thickness direction is aligned with the vertical direction. The first elongated portion 211A, the second elongated portion 211B, and the connecting portion 212 may be integrally formed from the same material.

[0036] The transport drive unit 22 is controlled by the control unit 90 to move the end effector 21 in three dimensions. For example, the transport drive unit 22 includes a forward / backward drive unit 23, a lifting / lowering drive unit 24, a rotation drive unit 25, and a movement drive unit 26. The forward / backward drive unit 23 moves the end effector 21 along the longitudinal direction of the first long section 211A and the second long section 211B. The forward / backward drive unit 23 includes, for example, a plurality of arms 231 and a plurality of motors 232. The plurality of arms 231 are rotatably coupled to each other. The tip of the coupled arm 231 is rotatably coupled to the coupling section 212 of the end effector 21, and the base of the coupled arm 231 is rotatably coupled to, for example, the lifting / lowering drive unit 24. A motor 232 is provided at each coupling section to change the coupling angle between the two members. The motors 232 work in conjunction to move the end effector 21 along its longitudinal direction.

[0037] The lifting drive unit 24 raises and lowers the end effector 21. The lifting drive unit 24 may raise and lower the end effector 21 and the forward / backward drive unit 23 together. The lifting drive unit 24 includes, for example, a drive source such as a motor and a power transmission unit that transmits the driving force of the drive source to the end effector 21. The power transmission unit includes, for example, a ball screw mechanism.

[0038] The rotary drive unit 25 rotates the end effector 21 around a predetermined axis of rotation. The predetermined axis of rotation is an axis aligned vertically. The rotary drive unit 25 rotates the end effector 21 between a rotation position where the tip of the end effector 21 faces the substrate housing C side and a rotation position where the tip of the end effector 21 faces the processing block 120 side. The rotary drive unit 25 may rotate the end effector 21, the forward / backward drive unit 23, and the lifting / lowering drive unit 24 as a single unit. The rotary drive unit 25 includes, for example, a motor.

[0039] The moving drive unit 26 moves the end effector 21 along the arrangement direction Dy of the load port 10. The moving drive unit 26 may move the end effector 21, the forward / backward drive unit 23, the lifting / lowering drive unit 24, and the rotational drive unit 25 as a single unit. If the part including the end effector 21, the forward / backward drive unit 23, the lifting / lowering drive unit 24, and the rotational drive unit 25 is considered as the first transport unit 20, then it can be said that the moving drive unit 26 moves the first transport unit 20 in the arrangement direction Dy. The moving drive unit 26 is fixed, for example, to the floor surface (bottom of the chamber) of the substrate transport device 110. For example, the moving drive unit 26 includes a drive source such as a motor and a power transmission unit that transmits the driving force of the drive source to the end effector 21. The power transmission unit includes, for example, a ball screw mechanism.

[0040] <Sensor> Sensor 30 is a sensor for detecting the position of the tip of the end effector 21. As shown in Figure 1, sensor 30 includes a light-emitting unit 31 and a light-receiving unit 32. Sensor 30 is located in front of the substrate housing C.

[0041] Figure 5 is a schematic perspective view showing an example of how the first transport unit 20 removes a substrate W, and Figure 6 is a schematic plan view showing an example of how the first transport unit 20 removes a substrate W. In the examples of Figures 5 and 6, the tip of the end effector 21 of the first transport unit 20 is located in the position immediately before it enters the substrate housing C. The position immediately before entry refers to the position where the end effector 21 faces the opening 55 of the substrate housing C in the horizontal direction, and where the tip of the end effector 21 has not yet entered the substrate housing C. Here, the tip of the end effector 21 corresponds to the tips of the first long portion 211A and the second long portion 211B. The entire end effector 21 located in the position immediately before entry does not face the substrate W inside the substrate housing C in the vertical direction. Note that the height position of the end effector 21 differs depending on the substrate W being loaded or unloaded, so the immediate position (height position) will differ depending on the height position of the substrate W being loaded or unloaded.

[0042] The immediate position is the position where the tip of the end effector 21 has not yet entered the board housing C. The distance between the board housing C and the tip of the end effector 21 in a plan view may be, for example, 100 mm or less, 50 mm or less, 20 mm or less, 10 mm or less, 5 mm or less, or 3 mm or less. A plan view here refers to viewing the object with the line of sight aligned with the vertical direction.

[0043] The light-emitting unit 31 outputs measurement light L1 toward the tip of the end effector 21 located directly in front of it. The measurement light L1 may be visible light or invisible light. The measurement light L1 may be, for example, infrared light. The light-emitting unit 31 may be a semiconductor light-emitting device such as a laser. The light-emitting unit 31 can also be said to be a light source. The light-emitting unit 31 is controlled, for example, by the control unit 90.

[0044] As shown in Figure 5, the tip portion to which the measurement light L1 is irradiated may be a portion of the end effector 21 that extends from the tip of the end effector 21 to a length of one-quarter of the longitudinal length of the end effector 21. For example, the tip portion may be a portion of the end effector 21 within 10 mm from the tip, a portion within 5 mm or less, or a portion within 3 mm. The tip portion to which the measurement light L1 is irradiated includes at least one of a portion of the first long portion 211A and a portion of the second long portion 211B.

[0045] In the examples shown in Figures 5 and 6, the light-emitting unit 31 is located to the side of the tip of the end effector 21 located in the immediate forward position. In other words, the light-emitting unit 31 faces the tip of the end effector 21 located in the immediate forward position in the alignment direction Dy. The light-emitting unit 31 is fixed to, for example, the floor surface of the substrate transport device 110.

[0046] The light-emitting unit 31 can output a measurement light L1 that is wider than the thickness (vertical thickness) of the tip of the end effector 21. In the example in Figure 5, the light-emitting unit 31 has an elongated shape with its longitudinal direction aligned with the vertical direction, and outputs a wide, sheet-like (or strip-like) measurement light L1 in the vertical direction. In other words, the light-emitting surface 31s of the light-emitting unit 31 has an elongated shape with its longitudinal direction aligned with the vertical direction, and its size in the longitudinal direction is wider than the thickness of the end effector 21. The measurement light L1 is emitted from the light-emitting surface 31s. The size of the light-emitting surface 31s in the vertical direction corresponds to the vertical width of the measurement light L1.

[0047] In the example shown in Figure 5, the light-emitting surface 31s has the following vertical dimensions. That is, the light-emitting surface 31s is large enough to illuminate the tip of the end effector 21 with the measurement light L1, regardless of which substrate W the end effector 21 is positioned directly in front of within the substrate housing C. For example, the upper end of the light-emitting surface 31s of the light-emitting unit 31 (the upper end of the measurement light L1) is above the uppermost substrate W in the substrate housing C, and the lower end of the light-emitting surface 31s (the lower end of the measurement light L1) is below the lowest substrate W in the substrate housing C. As a specific example, the upper end of the light-emitting surface 31s is above the ceiling 52 of the substrate housing C, and the lower end of the light-emitting surface 31s is below the bottom 51 of the substrate housing C.

[0048] The light-receiving unit 32 receives the measurement light L1 output by the light-emitting unit 31. In the example shown in Figure 5, the light-receiving unit 32 is located on the opposite side from the light-emitting unit 31 to the tip of the end effector 21 located directly in front of it. In other words, the light-emitting unit 31 and the light-receiving unit 32 are spaced apart in the arrangement direction Dy, and the tip of the end effector 21 located directly in front of it is located between the light-emitting unit 31 and the light-receiving unit 32. The light-receiving unit 32 is fixed to the floor of the substrate transport device 110, for example.

[0049] In the example shown in Figure 5, the light-receiving unit 32 has an elongated shape with its longitudinal direction aligned with the vertical. That is, the light-receiving surface 32s of the light-receiving unit 32 has an elongated shape with its longitudinal direction aligned with the vertical. The light-receiving surface 32s may be formed by light-receiving elements (pixels) not shown, arranged along the vertical direction. The measurement light L1 is received by the light-receiving surface 32s. Each light-receiving element outputs a signal corresponding to the intensity of the measurement light L1 incident on it. Such a light-receiving unit 32 may also be called a line sensor. The light-receiving unit 32 outputs a detection signal containing the signals of multiple light-receiving elements to the control unit 90. The detection signal indicates the spatial distribution of the intensity (or amount of light) of the measurement light L1 received by the light-receiving unit 32.

[0050] The light-receiving surface 32s has a vertical size approximately the same as the vertical size of the light-emitting surface 31s of the light-emitting unit 31. In other words, the vertical size of the light-receiving surface 32s is wider than, for example, the thickness of the tip of the end effector 21. The upper end of the light-receiving surface 32s may be above the uppermost substrate W in the substrate housing C, for example, above the ceiling 52 of the substrate housing C. The lower end of the light-receiving surface 32s may be below the lowermost substrate W in the substrate housing C, for example, below the bottom 51 of the substrate housing C. This allows the light-receiving unit 32 to receive the measurement light L1 more appropriately.

[0051] Figure 7 is a schematic diagram illustrating an example of the positional relationship between the end effector 21, the light receiving unit 32, and the measurement light L1. A portion of the measurement light L1 output by the light emitting unit 31 is blocked by the tip of the end effector 21. Specifically, a portion of the measurement light L1 is blocked by the first tip of the first long section 211A and the second tip of the second long section 211B. In the example in Figure 7, the portion of the measurement light L1 blocked by the end effector 21 is schematically shown with hatched lines. On the other hand, the portion of the measurement light L1 above and below the tip of the end effector 21 travels towards the light receiving unit 32 and is received by the light receiving unit 32. Therefore, the light receiving element corresponding to the tip of the end effector 21 receives almost no measurement light L1, while the other light receiving elements receive the measurement light L1.

[0052] Therefore, the spatial distribution of the intensity of the measurement light L1 received by the light receiving unit 32 reflects the position of the end effector 21. Specifically, the region with low intensity corresponds to the position of the end effector 21. Based on the measurement light L1 received by the light receiving unit 32 (i.e., the detection signal of the light receiving unit 32), the control unit 90 calculates the position of the tip of the end effector 21. For example, the control unit 90 may determine the height position of the tip of the end effector 21 by selecting a region of the detection signal that is smaller than a predetermined reference value.

[0053] Furthermore, the functional unit within the control unit 90 that calculates the position of the tip of the end effector 21 can also be said to belong to the sensor 30. This functional unit does not necessarily need to be implemented in the control unit 90; if the control unit is built into the sensor 30, it may be implemented in the control unit.

[0054] In the example described above, the end effector 21 is connected to the transport drive unit 22 at its base end (specifically, the connecting portion 212). Therefore, the end effector 21 has a cantilever structure. The tip of the end effector 21 is a free end, so it may be located lower than the base end of the end effector 21. This phenomenon is due to various factors such as the rigidity of the end effector 21, the fixing force between the end effector 21 and the transport drive unit 22, and the rigidity of the transport drive unit 22. The position of the tip of the end effector 21 may move downward due to variations in the equipment or deterioration over time. In Figure 7, an end effector 21 with a tip lower than the base end is shown by a dashed line. When the tip of the end effector 21 is located downward in this way, there is a risk of collision with the substrate W when entering the substrate housing C.

[0055] Furthermore, the end effector 21 may vibrate. Specifically, the end effector 21 may vibrate such that its tip moves back and forth vertically. The vibration of the end effector 21 is particularly large when the transport drive unit 22 is driven at a frequency close to its natural frequency. When the tip of the end effector 21 vibrates in this way, there is a risk of collision with the substrate W when it enters the substrate housing C.

[0056] Furthermore, even if the end effector 21 is horizontal, the height of the tip of the end effector 21 may shift due to errors in the lifting drive unit 24, etc. In this case as well, there is a risk that the tip of the end effector 21 may collide with the substrate W.

[0057] In this embodiment, the sensor 30 (control unit 90) detects the position of the tip of the end effector 21 based on the measurement light L1. In other words, the sensor 30 detects the position of the tip of the end effector 21 that is closer to the tip. Therefore, the control unit 90 can determine with higher accuracy whether the position of the tip of the end effector 21 is appropriate or not just before the end effector 21 enters the substrate housing C. In other words, the control unit 90 can determine with higher accuracy whether or not the tip of the end effector 21 will collide with the substrate W.

[0058] <Transportation Operation> Figure 8 is a flowchart illustrating an example of the operation of the substrate transport device 110. The operation of this substrate transport device 110 is realized by the control unit 90 controlling the first transport unit 20 and the sensor 30. Here, as an example, the operation of retrieving a substrate W from a substrate container C will be described.

[0059] First, the transport drive unit 22 starts driving the end effector 21 (step S1). Specifically, the transport drive unit 22 first stops the end effector 21 at a position facing the substrate container C. That is, the movement drive unit 26 moves the end effector 21 along the arrangement direction Dy, while the lifting drive unit 24 raises and lowers the end effector 21 to a height position corresponding to the substrate W to be transported. This height position is the height between the bottom surface of the substrate W to be transported and the top surface of the substrate W directly below it. Next, the rotation drive unit 25 rotates the end effector 21 to a rotation position where it can enter the inside of the substrate container C, using the forward / backward drive unit 23. Then, the forward / backward drive unit 23 moves the end effector 21 horizontally toward the substrate container C.

[0060] With the end effector 21 in the position immediately before it, the sensor 30 detects the position of the tip of the end effector 21 (step S2). Specifically, the light-emitting unit 31 outputs measurement light L1 toward the tip of the end effector 21, and the light-receiving unit 32 receives the measurement light L1. The light-receiving unit 32 outputs a detection signal corresponding to the measurement light L1 to the control unit 90. The control unit 90 calculates the position of the tip of the end effector 21 based on the detection signal. The transport drive unit 22 may stop the tip of the end effector 21 at the position immediately before it, and the sensor 30 may detect the position of the tip of the end effector 21 while the end effector 21 is stopped. Alternatively, the sensor 30 may detect the position of the tip of the end effector 21 while the tip of the end effector 21 is passing the position immediately before it.

[0061] Furthermore, the sensor 30 continuously detects the position of the tip of the end effector 21 over a predetermined period of time. In other words, the sensor 30 (control unit 90) generates time-series data of the position of the tip of the end effector 21. The predetermined period is, for example, a few seconds or less, and may be less than one second. If the end effector 21 is vibrating, the detected position in the time-series data will fluctuate over time.

[0062] Next, the control unit 90 determines whether the position of the tip of the end effector 21 is appropriate. For example, the control unit 90 determines whether the position fluctuation amount of the end effector 21, as described below, is greater than or equal to a fluctuation reference value (step S3). The position fluctuation amount is, for example, the position fluctuation amount of the tip of the end effector 21, and may also be the maximum value of the position fluctuation amount of the tip of the end effector 21 within a predetermined period. The maximum value of the position fluctuation amount is, for example, the amplitude of the vibration of the end effector 21. The fluctuation reference value is set in advance to a value such that the end effector 21 does not collide with the substrate W, and may be included in reference data D1 of the storage unit 94, for example (see Figure 2).

[0063] When the amount of positional fluctuation is greater than or equal to the fluctuation reference value, the control unit 90 performs vibration reduction processing to reduce the vibration of the end effector 21 (step S4). As a specific example, the control unit 90 stops the operation of the transport drive unit 22 as part of the vibration reduction processing. As a result, the amplitude of vibration of the end effector 21 decreases over time. Therefore, the amount of positional fluctuation of the end effector 21 will eventually fall below the fluctuation reference value.

[0064] The sensor 30 measures the position of the tip of the end effector 21 again (step S2), and the control unit 90 determines the relationship between the amount of position change and the reference value of the change (step S3). If the amount of position change is still greater than or equal to the reference value of the change, the control unit 90 continues to perform vibration reduction processing (step S4). One example of this vibration reduction processing is that the transport unit 20 is not driven until the amount of position change falls below the reference value of the change.

[0065] On the other hand, when the amount of position variation is less than the variation reference value, the control unit 90 calculates the difference between the measured position and the reference position of the end effector 21 (step S5). The detected position is the detected position of the tip of the end effector 21 after the amount of position variation has fallen below the variation reference value, and may be the most recent detected position or the average value of the detected positions at multiple timings. The reference position corresponds to the position of the end effector 21 when the substrate W to be shipped is removed. The reference position corresponding to each substrate W is set in advance and may be included in reference data D1, for example. The control unit 90 reads the reference position corresponding to the substrate W to be shipped from reference data D1 and calculates the difference between the reference position and the measured position.

[0066] Next, the control unit 90 determines whether the difference is greater than or equal to a predetermined difference reference value (step S6). The difference reference value is set in advance to a value such that the end effector 21 does not collide with the substrate W, and is included in reference data D1, for example. If the difference is less than the difference reference value, the control unit 90 does not execute step S7 described later, but controls the transport drive unit 22 to remove the substrate W with the end effector 21 (step S8). Specifically, the forward / backward drive unit 23 moves the end effector 21 horizontally toward the inside of the substrate housing C and stops the end effector 21 directly below the substrate W. Next, the lifting / lowering drive unit 24 raises the end effector 21 and lifts the substrate W with the end effector 21. Next, the forward / backward drive unit 23 retracts the end effector 21 from the substrate housing C. As a result, the substrate W is removed from the substrate housing C.

[0067] On the other hand, in step S6, if the difference is greater than or equal to the difference reference value, the control unit 90 controls the lifting drive unit 24 to raise or lower the end effector 21 so that the tip of the end effector 21 approaches the reference position (step S7). For example, the lifting drive unit 24 raises or lowers the end effector 21 toward the reference position by the amount of the difference. This makes the height position of the end effector 21 appropriate. Next, the control unit 90 controls the transport drive unit 22 to pick up the substrate W with the end effector 21 (step S8).

[0068] <Effects and Effects> As described above, in this embodiment, the sensor 30 is provided independently of the first transport unit 20 and optically detects the position of the tip of the end effector 21 located directly in front of it. Therefore, the position of the tip of the end effector 21 can be obtained with higher accuracy. As mentioned above, the end effector 21 enters the inside of the substrate housing C from its tip. Therefore, if the position of the tip of the end effector 21 is inappropriate, the tip of the end effector 21 will collide with the substrate W. In this embodiment, the sensor 30 detects the position of the tip of the end effector 21 that is closest to the tip. Therefore, the control unit 90 can determine with higher accuracy whether the position of the tip of the end effector 21 is appropriate or not, in terms of whether or not the end effector 21 will collide with the substrate W. In other words, the substrate transport device 110 contributes to avoiding collisions between the end effector 21 and the substrate W. Note that the sensor 30 may also detect the position of the tip of the end effector 21 itself as the tip of the end effector 21.

[0069] Furthermore, in the above example, the control unit 90 also monitors the amount of positional fluctuation (e.g., vibration amplitude) of the end effector 21 (step S3), and reduces the vibration of the end effector 21 when the amount of positional fluctuation is large (step S4). As a result, the substrate transport device 110 can more effectively reduce the possibility of the end effector 21 colliding with the substrate W.

[0070] Furthermore, in the example described above, the control unit 90 stops driving the transport unit 20 as a vibration reduction process until the amount of positional fluctuation falls below a fluctuation reference value. With this, the substrate transport device 110 can reduce vibration of the end effector 21 with simple control.

[0071] Furthermore, in the above example, the control unit 90 also monitors the position of the tip of the end effector 21 when the positional fluctuation is small (step S6), and when this position is far from the reference position, it adjusts the height of the end effector 21 to bring it closer to the reference position (step S7). As a result, the substrate transport device 110 can further appropriately reduce the possibility of the end effector 21 colliding with the substrate W.

[0072] Furthermore, in the above example, the light-emitting unit 31 and the light-receiving unit 32 are located on the side of the end effector 21, and the width (vertical width) of the measurement light L1 is wider than the thickness of the tip of the end effector 21. The width of the measurement light L1 may also be wider than the distance between the substrates W inside the substrate housing C. As a result, only a portion of the measurement light L1 is blocked by the end effector 21, and the portion of the measurement light L1 that travels vertically outside the end effector 21 is received by the light-receiving unit 32. This allows the sensor 30 (control unit 90) to calculate the height position of the end effector 21 with higher accuracy.

[0073] Furthermore, in the example described above, the upper end of the light-emitting surface 31s and the upper end of the light-receiving surface 32s are above the uppermost substrate W in the substrate housing C, while the lower end of the light-emitting surface 31s and the lower end of the light-receiving surface 32s are below the lowermost substrate W in the substrate housing C. Therefore, whenever the first transport unit 20 takes out any substrate W, the light-emitting unit 31 can output the measurement light L1 to the tip of the end effector 21. Consequently, the sensor 30 can detect the position of the tip of the end effector 21.

[0074] Furthermore, in the example described above, the end effector 21 located in the immediate forward position is positioned between the light-emitting unit 31 and the light-receiving unit 32. Therefore, the measurement light L1 from the light-emitting unit 31 is blocked by both the first tip of the first long portion 211A and the second tip of the second long portion 211B. Conversely, the light-receiving unit 32 receives the measurement light L1 in an area other than the region where the first tip of the first long portion 211A and the second tip of the second long portion 211B overlap when viewed along the array direction Dy. Thus, the sensor 30 (control unit 90) can obtain the average height position of the first long portion 211A and the second long portion 211B. More generally, the control unit 90 can obtain the average height position of the height position distribution of the end effector 21 in the array direction Dy and monitor this height position. According to this, the control unit 90 can monitor the average height position of the first tip of the first elongated portion 211A and the second tip of the second elongated portion 211B, and can also monitor vibrations of both the first tip of the first elongated portion 211A and the second tip of the second elongated portion 211B.

[0075] <End effector 21 sagging> Sensor 30 detects the height position of the tip of the end effector 21. Alternatively, another sensor may be provided to detect the height position of the base of the end effector 21. For example, this additional sensor may be built into the lifting drive unit 24. This additional sensor may also be an encoder. When the difference between the base of the end effector 21 measured by the additional sensor and the tip of the end effector 21 measured by sensor 30 is greater than or equal to a predetermined sag reference value, the control unit 90 may notify the outside that a sag abnormality has occurred in the end effector 21. For example, the control unit 90 may notify the outside of the abnormality using a display or sound output unit (not shown). The display may be a liquid crystal display, and the sound output unit may be, for example, a speaker or a buzzer.

[0076] In the example shown in Figure 5, the light-emitting unit 31 is positioned facing the first elongated portion 211A, and the light-receiving unit 32 is positioned facing the second elongated portion 211B. However, the positions of the light-emitting unit 31 and the light-receiving unit 32 may be reversed.

[0077] Furthermore, although the above example employs non-driving of the transport unit 20 as a vibration reduction process, it is not necessarily limited to this. The transport unit 20 may be provided with a vibrator that applies vibrations to the end effector 21 that are in the opposite phase to the vibrations of the end effector 21. The vibrations of the vibrator can reduce the vibrations of the end effector 21 more quickly. For example, a piezoelectric element or an eccentric motor can be used as the vibrator.

[0078] Furthermore, although the above example describes the unloading operation of the substrate W, the same applies to the loading operation. However, in the loading operation, the substrate W is placed on the end effector 21. Therefore, the measurement light L1 from the light-emitting unit 31 is blocked by the tip of the end effector 21 and the substrate W. For this reason, the spatial distribution of the measurement light L1 received by the light-receiving unit 32 depends on the tip of the end effector 21 and the substrate W. Specifically, the area obtained by subtracting the thickness of the substrate W from the area of ​​the spatial distribution of the measurement light L1 that is smaller than a reference value corresponds to the tip of the end effector 21. Since the thickness of the substrate W can be set in advance, the sensor 30 can detect the position of the tip of the end effector 21 based on the spatial distribution of the measurement light L1 and the thickness of the substrate W.

[0079] <Second Embodiment> The substrate transport device 110 according to the second embodiment is the same as the substrate transport device 110 according to the first embodiment, except for the configuration of the sensor 30. Figures 9 and 10 are schematic perspective views showing a first example of a part of the configuration of the substrate transport device 110 according to the second embodiment. As shown in Figure 9, the sensor 30 includes a first light-emitting unit 31A, a first light-receiving unit 32A, a second light-emitting unit 31B, a second light-receiving unit 32B, and a sensor movement drive unit 33.

[0080] The first light-emitting unit 31A outputs measurement light L1 to the first tip of the first elongated portion 211A of the end effector 21 located directly in front of it. Hereinafter, the measurement light L1 output by the first light-emitting unit 31A will also be referred to as the first measurement light L11. In the example shown in Figure 9, the first light-emitting unit 31A is provided to the side of the first elongated portion 211A of the end effector 21 located directly in front of it. An example of the configuration of the first light-emitting unit 31A is the same as that of the light-emitting unit 31 in the first embodiment.

[0081] The first light-receiving unit 32A receives the first measurement light L11 output by the first light-emitting unit 31A. In the examples of Figures 9 and 10, the sensor movement drive unit 33 moves the first light-receiving unit 32A between the first measurement position and the first standby position. Figure 9 shows the first light-receiving unit 32A located at the first measurement position, and Figure 10 shows the first light-receiving unit 32A located at the first standby position.

[0082] The first measurement position is where the first light-receiving unit 32A is located between the first long portion 211A and the second long portion 211B of the end effector 21, with the first tip positioned directly in front of it. In the example shown in Figure 9, the first light-receiving unit 32A is positioned at the first measurement position and is aligned with the first light-emitting unit 31A in the alignment direction Dy, and receives the first measurement light L11 from the first light-emitting unit 31A. The first light-receiving unit 32A outputs a first detection signal to the control unit 90 that indicates the spatial distribution of the intensity of the received first measurement light L11. An example of the configuration of the first light-receiving unit 32A is the same as that of the light-receiving unit 32 in the first embodiment.

[0083] When the first light-receiving unit 32A is positioned at the first measurement position, the end effector 21 cannot move into the substrate housing C. This is because the first light-receiving unit 32A is located in the movement path of the end effector 21, causing the end effector 21 to collide with the first light-receiving unit 32A. The first standby position is a position that avoids the movement path of the end effector 21. For example, the first standby position may be located below the first measurement position, and the upper end of the first light-receiving unit 32A may be located below the lower end of the substrate housing C.

[0084] The second light-emitting unit 31B outputs measurement light L1 to the second tip of the second long portion 211B of the end effector 21 located in the immediate front position. Hereinafter, the measurement light L1 output by the second light-emitting unit 31B will also be referred to as the second measurement light L12. In the examples of Figures 9 and 10, the sensor movement drive unit 33 moves the second light-emitting unit 31B between the second measurement position and the second standby position. Figure 9 shows the second light-emitting unit 31B located at the second measurement position, and Figure 10 shows the second light-emitting unit 31B located at the second standby position.

[0085] The second measurement position is where the second light-emitting unit 31B is located between the first long portion 211A and the second long portion 211B of the end effector 21, with the second tip positioned directly in front of it. With the second light-emitting unit 31B positioned at the second measurement position, it outputs the second measurement light L12 toward the second tip of the second long portion 211B. An example of the configuration of the second light-emitting unit 31B is the same as that of the light-emitting unit 31 in the first embodiment.

[0086] On the other hand, when the second light-emitting unit 31B is located at the second measurement position, the end effector 21 cannot move into the substrate housing C. This is because the second light-emitting unit 31B is located on the movement path of the end effector 21, causing the end effector 21 to collide with the second light-emitting unit 31B. The second standby position is a position that avoids the movement path of the end effector 21. For example, the second standby position may be located below the second measurement position, and the upper end of the second light-emitting unit 31B may be below the lower end of the substrate housing C. In the second standby position, the second measurement light L12 from the second light-emitting unit 31B does not irradiate the second long portion 211B of the end effector 21.

[0087] The second light-receiving unit 32B receives the second measurement light L12 output by the second light-emitting unit 31B, which has stopped at the second measurement position. The second light-receiving unit 32B outputs a second detection signal to the control unit 90 that indicates the spatial distribution of the intensity of the second measurement light L12 that it has received. In the example of Figure 9, the second light-receiving unit 32B is located to the side of the second elongated portion 211B of the end effector 21, where the second tip is located in the immediate forward position. In the example of Figure 9, the second light-receiving unit 32B is aligned with the second light-emitting unit 31B located at the second measurement position in the alignment direction Dy, and the second elongated portion 211B of the end effector 21, where the second tip is located in the immediate forward position, is located between the second light-emitting unit 31B located at the second measurement position and the second light-receiving unit 32B. An example of the configuration of the second light-receiving unit 32B is the same as that of the light-receiving unit 32 according to the first embodiment.

[0088] The sensor movement drive unit 33 may include, for example, a drive source such as a motor and a power transmission unit that transmits the driving force of the drive source to the first light receiving unit 32A and the second light emitting unit 31B. The power transmission unit may include, for example, a ball screw mechanism. The sensor movement drive unit 33 is provided, for example, on the floor surface of the substrate transport device 110. In the examples of Figures 9 and 10, the sensor movement drive unit 33 moves the first light receiving unit 32A and the second light emitting unit 31B together, but they may be moved individually. The sensor movement drive unit 33 is controlled by the control unit 90. In the above example, the sensor movement drive unit 33 raises and lowers the first light receiving unit 32A and the second light emitting unit 31B, so it can also be said to be a lifting drive unit.

[0089] The control unit 90 calculates the position of the first tip of the first elongated portion 211A based on the first detection signal from the first light receiving unit 32A, and calculates the position of the second tip of the second elongated portion 211B based on the second detection signal from the second light receiving unit 32B.

[0090] As described above, in the second embodiment, the control unit 90 can individually obtain the position of the first tip of the first elongated portion 211A and the position of the second tip of the second elongated portion 211B.

[0091] An example of the operation of the substrate transport device 110 according to the second embodiment is the same as in Figure 8. However, in step S2, the sensor movement drive unit 33 moves the first light receiving unit 32A and the second light emitting unit 31B to the first measurement position and the second measurement position, respectively. The first light emitting unit 31A outputs the first measurement light L11, and the second light emitting unit 31B outputs the second measurement light L12. The first light emitting unit 31A and the second light emitting unit 31B may output the first measurement light L11 and the second measurement light L12 in parallel with each other (for example, simultaneously). The first light receiving unit 32A receives the first measurement light L11, and the second light receiving unit 32B receives the second measurement light L12. The control unit 90 calculates the position of the first tip of the first elongated portion 211A based on the first detection signal from the first light receiving unit 32A, and calculates the position of the second tip of the second elongated portion 211B based on the second detection signal from the second light receiving unit 32B.

[0092] In step S3, the control unit 90 calculates the positional displacement of the first tip of the first long section 211A and the positional displacement of the second tip of the second long section 211B, and determines whether each positional displacement is greater than or equal to a fluctuation reference value. If at least one of the positional displacements is greater than or equal to the fluctuation reference value, the control unit 90 performs vibration reduction processing (step S4).

[0093] When both position fluctuation amounts are less than the fluctuation reference value, the control unit 90 calculates the difference between the detected position of the first long section 211A and the reference position, and calculates the difference between the detected position of the second long section 211B and the reference position (step S5). The control unit 90 determines whether each difference is greater than or equal to the difference reference value (step S6), and when at least one of the differences is greater than or equal to the difference reference value, it controls the lifting drive unit 24 to adjust the position of the end effector 21 (step S7). Specifically, the lifting drive unit 24 raises and lowers the end effector 21 so that both the first long section 211A and the second long section 211B (for example, both the first tip and the second tip) are located within a predetermined range. The predetermined range is, for example, a predetermined range that includes the reference position. As an example, the predetermined range is the range between an upper position that is above the reference position by the difference reference value and a lower position that is below the reference position by the difference reference value.

[0094] In step S8, first, the sensor movement drive unit 33 moves the first light receiving unit 32A and the second light emitting unit 31B to the first and second standby positions, respectively. Then, the transport drive unit 22 moves the end effector 21 to remove the substrate W from the substrate housing C.

[0095] As described above, in the second embodiment, the sensor 30 individually detects the position of the first tip of the first long portion 211A and the position of the second tip of the second long portion 211B. Therefore, the control unit 90 can monitor both positions individually. For example, the control unit 90 can more reliably reduce the vibration of the first long portion 211A and the vibration of the second long portion 211B. For example, if the vibrator is provided on the first transport unit 20, the control unit 90 may vibrate the vibrator in the opposite phase to the larger of the vibrations of the first long portion 211A and the second long portion 211B. This allows the vibration of the end effector 21 to be reduced more quickly. Also, for example, after vibration reduction, the control unit 90 can control the lifting drive unit 24 to more reliably bring the detection positions of both the first long portion 211A and the second long portion 211B within a predetermined range.

[0096] Note that the positions of the first light-emitting unit 31A and the first light-receiving unit 32A may be reversed, and the positions of the second light-emitting unit 31B and the second light-receiving unit 32B may be reversed. Here, of the first light-emitting unit 31A and the first light-receiving unit 32A, the one located between the first long portion 211A and the second long portion 211B is called the first inner optical unit, and the other is called the first outer optical unit. Similarly, of the second light-emitting unit 31B and the second light-receiving unit 32B, the one located between the first long portion 211A and the second long portion 211B is called the second inner optical unit, and the other is called the second outer optical unit. The sensor movement drive unit 33 moves the first inner optical unit between the first measurement position and the first standby position, and moves the second inner optical unit between the second measurement position and the second standby position.

[0097] The sensor 30 can detect the position of the first tip of the first elongated portion 211A when the first inner optical unit is in the first measurement position, and can detect the position of the second tip of the second elongated portion 211B when the second inner optical unit is in the second measurement position. Furthermore, the end effector 21 can enter the inside of the substrate housing C when the first inner optical unit and the second inner optical unit are in the first and second standby positions, respectively.

[0098] Figure 11 is a schematic perspective view showing a second example of the configuration of a substrate transport device 110 according to the second embodiment. In the example in Figure 11, the first light-emitting unit 31A and the first light-receiving unit 32A are located to the side of the first long portion 211A of the end effector 21, where the first tip is located directly in front. Specifically, both the first light-emitting unit 31A and the first light-receiving unit 32A are located on the opposite side of the second long portion 211B from the first long portion 211A. The first light-emitting unit 31A outputs the first measurement light L11 toward the first tip of the first long portion 211A. An example of the first light-emitting unit 31A is the same as the light-emitting unit 31 according to the first embodiment. A portion of the first measurement light L11 from the first light-emitting unit 31A is reflected by the side of the tip of the first long portion 211A. The first light-receiving unit 32A receives the first measurement light L11 reflected by the first long portion 211A. An example of the configuration of the first light-receiving unit 32A is the same as that of the light-receiving unit 32 according to the first embodiment.

[0099] As shown in Figure 11, the first light-receiving unit 32A may be adjacent to the first light-emitting unit 31A in a horizontal forward / backward direction Dx perpendicular to the arrangement direction Dy. The first light-emitting unit 31A and the first light-receiving unit 32A may be provided within the same housing. Hereinafter, the first light-emitting unit 31A and the first light-receiving unit 32A formed integrally within the same housing will also be referred to as the first light-emitting and light-receiving unit 30A. Note that the positions of the first light-emitting unit 31A and the first light-receiving unit 32A may be reversed.

[0100] Figure 12 is a schematic diagram illustrating an example of the positional relationship between the first light-emitting unit 31A, the first light-receiving unit 32A, and the first tip of the first elongated portion 211A. In the example of Figure 12, the first measurement light L11 output from the first light-emitting unit 31A is schematically shown with wide diagonal hatching. The light of this first measurement light L11 that incident on the tip of the first elongated portion 211A is reflected by the first elongated portion 211A. In the example of Figure 12, the reflected first measurement light L11 is shown with narrow dashed diagonal hatching. The reflected first measurement light L11 is incident on some of the multiple light-receiving elements of the first light-receiving unit 32A. The portions of the first measurement light L11 from the first light-emitting unit 31A that are above and below the first elongated portion 211A do not incident on the first elongated portion 211A and continue onward. Therefore, the measurement light L1 hardly enters any of the photodetectors in the first light-receiving unit 32A other than the aforementioned some photodetectors. Consequently, the spatial distribution of the intensity of the first measurement light L11 received by the first light-receiving unit 32A reflects the position of the first tip of the first elongated portion 211A. Specifically, the region with high intensity corresponds to the position of the first tip of the first elongated portion 211A.

[0101] Therefore, the control unit 90 calculates the position of the first tip of the first elongated portion 211A based on the first measurement light L11 received by the first light receiving unit 32A (i.e., the first detection signal of the first light receiving unit 32A). For example, the control unit 90 may determine the height position of the first tip of the first elongated portion 211A as the region of the first detection signal that is greater than a predetermined reference value. As described above, the sensor 30 (control unit 90) can detect the position of the portion of the tip of the end effector 21 that reflects the first measurement light L11.

[0102] The second light-emitting unit 31B and the second light-receiving unit 32B are located to the side of the second elongated portion 211B of the end effector 21, where the second tip is located directly in front. Specifically, both the second light-emitting unit 31B and the second light-receiving unit 32B are located on the opposite side of the second elongated portion 211B from the first elongated portion 211A. The second light-emitting unit 31B outputs the second measurement light L12 toward the second tip of the second elongated portion 211B. An example of the configuration of the second light-emitting unit 31B is the same as that of the light-emitting unit 31 in the first embodiment. A portion of the second measurement light L12 from the second light-emitting unit 31B is reflected by the tip of the second elongated portion 211B. The second light-receiving unit 32B receives the second measurement light L12 reflected by the second elongated portion 211B. An example of the configuration of the second light-receiving unit 32B is the same as that of the light-receiving unit 32 in the first embodiment.

[0103] As shown in Figure 11, the second light-receiving unit 32B may be adjacent to the second light-emitting unit 31B in the forward / backward direction Dx. The second light-emitting unit 31B and the second light-receiving unit 32B may be provided within the same housing. Hereinafter, the second light-emitting unit 31B and the second light-receiving unit 32B formed integrally within the same housing will also be referred to as the second light-emitting and light-receiving unit 30B. Note that the positions of the second light-emitting unit 31B and the second light-receiving unit 32B may be reversed.

[0104] The control unit 90 calculates the position of the second tip of the second long portion 211B based on the second measurement light L12 received by the second light receiving unit 32B (i.e., the second detection signal of the second light receiving unit 32B), similar to the first long portion 211A.

[0105] Incidentally, the first measurement light L11 from the first light-emitting unit 31A acts as noise for the second light-receiving unit 32B. Therefore, the first light-emitting unit 31A may be positioned so that the first measurement light L11 hardly enters the second light-receiving unit 32B. This can reduce the generation of noise in the second detection signal. Similarly, the second light-emitting unit 31B may be positioned so that the second measurement light L12 hardly enters the first light-receiving unit 32A.

[0106] Alternatively, the wavelength of the first measurement light L11 output by the first light-emitting unit 31A may differ from the wavelength of the second measurement light L12 output by the second light-emitting unit 31B. The wavelength difference may be, for example, 1 nm or more, 10 nm or more, or 100 nm or more. Furthermore, the wavelength band that the first light-receiving unit 32A can receive includes the wavelength of the first measurement light L11 from the first light-emitting unit 31A, but does not include the wavelength of the second measurement light L12 from the second light-emitting unit 31B. Similarly, the wavelength band that the second light-receiving unit 32B can receive includes the wavelength of the second measurement light L12 from the second light-emitting unit 31B, but does not include the wavelength of the first measurement light L11 from the first light-emitting unit 31A. This also helps to reduce noise generation. This point is the same for the first example and the other examples described later.

[0107] According to the second example of the second embodiment, the first light-emitting unit 31A, the first light-receiving unit 32A, the second light-emitting unit 31B, and the second light-receiving unit 32B are arranged to avoid the movement path of the end effector 21. Therefore, the sensor 30 does not obstruct the movement of the end effector 21. Thus, unlike the first example of the second embodiment, it is unnecessary for the sensor 30 to move forward and backward for the end effector 21. As a result, the throughput of the substrate transport device 110 can be improved, and manufacturing costs can be reduced.

[0108] Figure 13 is a schematic perspective view showing a third example of the configuration of a substrate transport device 110 according to the second embodiment. In the example in Figure 13, a plurality of first light-emitting units 31A and a plurality of first light-receiving units 32A are provided. Specifically, the first light-emitting units 31A and the first light-receiving units 32A are provided in a one-to-one correspondence. In the example in Figure 13, the first light-emitting units 31A and the first light-receiving units 32A that correspond to each other form a first light-emitting and light-receiving unit 30A. The plurality of first light-emitting and light-receiving units 30A are arranged vertically along the side of the first elongated portion 211A of the end effector 21 located directly in front of it.

[0109] Each first light-emitting and light-receiving unit 30A is provided according to the height position of the substrate W to be loaded and unloaded. Figure 14 is a schematic diagram showing an example of the positional relationship between the first light-emitting and light-receiving unit 30A and the substrate housing C. In the example of Figure 14, the positions of the first long portion 211A and the second long portion 211B when each substrate W is removed are shown by dashed lines. In the example of Figure 14, nine substrates W are shown for simplicity. In the example of Figure 14, the uppermost first light-emitting and light-receiving unit 30A is provided in a position capable of detecting the position of the first tip of the first long portion 211A when the uppermost substrate W in the substrate housing C is loaded and unloaded. In the example of Figure 14, the uppermost first light-emitting and light-receiving unit 30A can detect the position of the first tip of each of the multiple (three in the figure) substrates W when they are loaded and unloaded. The detectable height range of the first light-emitting and light-receiving unit 30A is adjusted by the width (vertical width) of the light-emitting surface 31s of the first light-emitting unit 31A and the width (vertical width) of the light-receiving surface 32s of the first light-receiving unit 32A. In the example shown in Figure 14, three first light-emitting and light-receiving units 30A are provided. The uppermost first light-emitting and light-receiving unit 30A corresponds to the top three substrates W, the middle first light-emitting and light-receiving unit 30A corresponds to the middle three substrates W, and the lowermost first light-emitting and light-receiving unit 30A corresponds to the bottom three substrates W. The position of the first leading edge of the first long portion 211A when each substrate W is loaded or unloaded is detected by one of the first light-emitting and light-receiving units 30A.

[0110] In the examples shown in Figures 13 and 14, multiple second light-emitting units 31B and multiple second light-receiving units 32B are also provided. The multiple second light-emitting units 31B and multiple second light-receiving units 32B are similar to the multiple first light-emitting units 31A and multiple first light-receiving units 32A, respectively.

[0111] According to the third example of the second embodiment, the vertical size of the first light-emitting unit 31A and the second light-receiving unit 32B is smaller. Now, in order for the first light-receiving unit 32A to properly receive the first measurement light L11 from the first light-emitting unit 31A, the first light-emitting unit 31A and the first light-receiving unit 32A must be installed so that the longitudinal direction of the light-emitting surface 31s of the first light-emitting unit 31A is parallel to the longitudinal direction of the light-receiving surface 32s of the first light-receiving unit 32A. If the vertical size of the first light-emitting unit 31A and the first light-receiving unit 32A is smaller, the required precision for mounting the first light-emitting unit 31A and the first light-receiving unit 32A can be reduced. Therefore, the manufacturing cost of the substrate transport device 110 can be reduced. The same applies to the second light-emitting unit 31B and the second light-receiving unit 32B.

[0112] Figure 15 is a schematic perspective view showing a fourth example of the configuration of a substrate transport device 110 according to the second embodiment. In the example of Figure 15, a single first light-emitting unit 31A and a single first light-receiving unit 32A are provided. The width of the first measurement light L11 from the first light-emitting unit 31A (the vertical size of the light-emitting surface 31s) is wider than the thickness of the first tip of the first elongated portion 211A. The width of the first measurement light L11 may be 10 times or less the thickness of the first tip, 5 times or less, or 3 times or less. The vertical size of the light-receiving surface 32s of the first light-receiving unit 32A is the same as the size of the light-emitting surface 31s of the first light-emitting unit 31A. In the example of Figure 15, the first light-emitting unit 31A and the first light-receiving unit 32A form a first light-emitting and light-receiving unit 30A.

[0113] The substrate transport device 110 further includes a sensor lifting drive unit 34. The sensor lifting drive unit 34 is controlled by a control unit 90 to raise and lower the first light-emitting unit 31A and the first light-receiving unit 32A (for example, the first light-emitting and light-receiving unit 30A). The sensor lifting drive unit 34 includes a drive source such as a motor and a power transmission unit that transmits the driving force of the drive source to the first light-emitting and light-receiving unit 30A. The power transmission unit includes, for example, a ball screw mechanism.

[0114] The sensor lifting drive unit 34 raises and lowers the first light-emitting and light-receiving unit 30A according to the position of the substrate W to be moved in and out of the substrate housing C. Specifically, the sensor lifting drive unit 34 raises and lowers the first light-emitting and light-receiving unit 30A to a position where it can detect the position of the tip of the end effector 21 located in the position immediately before the substrate W to be moved in and out. For example, when the end effector 21 moves the top substrate W in the substrate housing C, the end effector 21 passes the position immediately before the top substrate W. The sensor lifting drive unit 34 raises and lowers the first light-emitting and light-receiving unit 30A to a position where it can irradiate the tip of the end effector 21 located in the position immediately before with the first measuring light L11. This position is set in advance and stored, for example, in the storage unit 94. In this state, the first light-emitting unit 31A outputs the first measurement light L11, the first light-receiving unit 32A receives the first measurement light L11 reflected by the first long portion 211A, and the control unit 90 calculates the position of the first tip of the first long portion 211A based on the first detection signal from the first light-receiving unit 32A. When loading or unloading substrates W other than the top layer, the sensor lifting drive unit 34 raises and lowers the first light-emitting and light-receiving unit 30A in the same manner.

[0115] In the example shown in Figure 15, a single second light-emitting unit 31B and a single second light-receiving unit 32B are provided. The second light-emitting unit 31B and the second light-receiving unit 32B are the same as the first light-emitting unit 31A and the first light-receiving unit 32A, respectively. The sensor lifting and lowering drive unit 34 also lifts and lowers the second light-emitting unit 31B and the second light-receiving unit 32B in the same way as the first light-emitting unit 31A and the first light-receiving unit 32A.

[0116] According to the fourth example of the second embodiment, a smaller first light-emitting unit 31A and a smaller first light-receiving unit 32A can be used. This further reduces the required precision for mounting the first light-emitting unit 31A and the first light-receiving unit 32A. Also, the number of first light-emitting units 31A and first light-receiving units 32A is reduced. Consequently, the manufacturing cost of the substrate transport device 110 can be reduced. The same applies to the second light-emitting unit 31B and the second light-receiving unit 32B.

[0117] Figure 16 is a schematic perspective view showing a fifth example of the configuration of a substrate transport device 110 according to the second embodiment. In the example of Figure 16, the first light-emitting unit 31A and the first light-receiving unit 32A are provided above the first elongated portion 211A of the end effector 21, where the first tip is located in the immediate front position. The first light-emitting unit 31A and the first light-receiving unit 32A are fixed, for example, to the chamber of the substrate transport device 110. The first light-emitting unit 31A and the first light-receiving unit 32A may be provided above the movement path of the end effector 21 when loading and unloading the uppermost substrate W in the substrate container C. With this configuration, the first light-emitting unit 31A and the first light-receiving unit 32A do not obstruct the movement of the end effector 21.

[0118] The first light-emitting unit 31A outputs the first measurement light L11 toward the first tip of the first elongated portion 211A of the end effector 21 located directly in front of it. The first light-emitting unit 31A may also cause the first measurement light L11 to incident on the upper surface of the first elongated portion 211A in a spot or line shape. The first light-emitting unit 31A emits the first measurement light L11 diagonally downward. The first measurement light L11 reflected from the upper surface of the first elongated portion 211A is received by the first light-receiving unit 32A.

[0119] The first light-receiving unit 32A may be adjacent to the first light-emitting unit 31A in the horizontal direction. In the example shown in Figure 16, the first light-receiving unit 32A is adjacent to the first light-emitting unit 31A in the forward / backward direction Dx. The first light-receiving unit 32A may be housed in the same housing as the first light-emitting unit 31A to form the first light-emitting and light-receiving unit 30A.

[0120] Since the measurement light L1 travels diagonally downward, the incident region in which the measurement light L1 enters the upper surface of the first long section 211A changes according to the height of the first long section 211A. Therefore, the position in which the first measurement light L11 reflected by the first long section 211A enters the first light receiving section 32A also changes according to the height of the first long section 211A. For example, when the first long section 211A is at its highest position, almost all of the first measurement light L11 enters the light receiving surface 32s of the first light receiving section 32A, and as the first long section 211A descends, a portion of the first measurement light L11 moves away from the light receiving surface 32s of the first light receiving section 32A. In this case, the intensity (amount of light) of the first measurement light L11 received by the first light receiving section 32A changes according to the height of the first long section 211A.

[0121] Therefore, the sensor 30 (control unit 90) may calculate the position of the first tip of the first elongated portion 211A according to the intensity of the first measuring light L11 received by the first light receiving unit 32A. For example, the correspondence between the intensity of the first measuring light L11 and the position of the first tip of the first elongated portion 211A may be set in advance by simulation or experiment, and correspondence relationship data showing this correspondence may be stored in, for example, the storage unit 94. The control unit 90 may calculate the position of the first tip of the first elongated portion 211A based on the intensity of the first measuring light L11 received by the first light receiving unit 32A and the correspondence relationship data.

[0122] Alternatively, regardless of the height position of the first elongated portion 211A, almost all of the first measurement light L11 may be incident on the light-receiving surface 32s of the first light-receiving unit 32A. However, the incident position on the light-receiving surface 32s changes according to the height position of the first elongated portion 211A. Such an incident position corresponds, for example, to a region of high intensity on the light-receiving surface 32s. Therefore, the correspondence between the incident position of the first measurement light L11 and the position of the first tip of the first elongated portion 211A is set in advance by simulation or experiment, and correspondence relationship data showing this correspondence is stored, for example, in the storage unit 94. The control unit 90 may calculate the position of the first tip of the first elongated portion 211A based on the incident position of the first measurement light L11 received by the first light-receiving unit 32A and the correspondence relationship data.

[0123] The second light-emitting section 31B and the second light-receiving section 32B are positioned above the second elongated portion 211B of the end effector 21, where the second tip is located in the immediate front position. The positional relationship between the second light-emitting section 31B, the second light-receiving section 32B, and the second elongated portion 211B of the end effector 21 is the same as that between the first light-emitting section 31A, the first light-receiving section 32A, and the first elongated portion 211A of the end effector 21. Furthermore, the method for calculating the position of the second tip of the second elongated portion 211B is the same as the method for calculating the position of the first tip of the first elongated portion 211A.

[0124] According to the fifth example of the second embodiment, a compact first light-emitting unit 31A and a compact first light-receiving unit 32A can be used. The same applies to the second light-emitting unit 31B and the second light-receiving unit 32B.

[0125] Incidentally, when the first transport unit 20 loads the substrate W into the substrate housing C, the substrate W is placed on the end effector 21, whose leading edge is located in the immediate front position. For this reason, the first light-emitting unit 31A and the second light-emitting unit 31B output measurement light L1 to the upper surface of the substrate W. The first measurement light L11 from the first light-emitting unit 31A is reflected in the first incident region on the upper surface of the substrate W and received by the first light-receiving unit 32A. The first incident region is the area directly above the first long portion 211A. The second measurement light L12 from the second light-emitting unit 31B is reflected in the second incident region on the upper surface of the substrate W and received by the second light-receiving unit 32B. The second incident region is the area directly above the second long portion 211B. Since the intensity and incident position of the first measurement light L11 received by the first light receiving unit 32A change according to the height position of the first incident region of the substrate W, the control unit 90 can calculate the height position of the first incident region of the substrate W based on the first detection signal. Similarly, the control unit 90 can calculate the height position of the second incident region of the substrate W based on the second detection signal.

[0126] However, since the reflectivity of the upper surface of the substrate W may differ from that of the end effector 21, the correspondence between intensity and position will differ from the correspondence when the measurement light L1 is incident on the end effector 21. The correspondence data for when the measurement light L1 is incident on the substrate W is set in advance and stored, for example, in the storage unit 94. When the substrate W is loaded into the substrate housing C, the control unit 90 reads out the correspondence data for loading the substrate W, and when the substrate W is unloaded from the substrate housing C, it reads out the correspondence data for unloading the substrate W.

[0127] Figure 17 is a schematic perspective view showing a sixth example of the configuration of a substrate transport device 110 according to the second embodiment. In the example of Figure 17, the first light-emitting unit 31A and the first light-receiving unit 32A are provided below the first long portion 211A of the end effector 21, where the first tip is located in the immediate front position, and the second light-emitting unit 31B and the second light-receiving unit 32B are provided below the second long portion 211B of the end effector 21, where the second tip is located in the immediate front position. Therefore, the first light-emitting unit 31A outputs a first measurement light L11 toward the lower surface of the first long portion 211A, and the second light-emitting unit 31B outputs a second measurement light L12 toward the lower surface of the second long portion 211B. The first measuring light L11 is reflected from the lower surface of the first elongated portion 211A and received by the first light receiving unit 32A, and the control unit 90 calculates the position of the first tip of the first elongated portion 211A based on the first detection signal of the first light receiving unit 32A. The second measuring light L12 is reflected from the lower surface of the second elongated portion 211B and received by the second light receiving unit 32B, and the control unit 90 calculates the position of the second tip of the second elongated portion 211B based on the second detection signal of the second light receiving unit 32B.

[0128] According to the sixth example of the second embodiment, regardless of whether the end effector 21 supports the substrate W, the measurement light L1 from the first light-emitting unit 31A and the second light-emitting unit 31B is incident on the lower surface of the end effector 21. Therefore, the control unit 90 can use common correspondence data regardless of whether the substrate W is being loaded or unloaded.

[0129] Figures 18 and 19 are schematic perspective views showing a seventh example of the configuration of a substrate transport device 110 according to the second embodiment. The seventh example of the substrate transport device 110 further includes a sensor lifting drive unit 34 compared to the fifth example of the substrate transport device 110. The sensor lifting drive unit 34 raises and lowers the sensor 30. Specifically, the sensor lifting drive unit 34 raises and lowers the sensor 30 (first light-emitting unit 31A, first light-receiving unit 32A, second light-emitting unit 31B, and second light-receiving unit 32B) according to the height position of the substrate W to be transported. In short, the sensor lifting drive unit 34 raises and lowers the sensor 30 according to the height position of the position directly in front of the end effector 21 so that the vertical distance between the end effector 21 and the sensor 30 is within a predetermined distance range. More specifically, the sensor 30 is moved to a height position a predetermined height above the position directly in front of the end effector 21 (specifically, the reference position) when loading and unloading the substrate W. The predetermined height is set in advance and stored, for example, in the memory unit 94.

[0130] In the example in Figure 18, the end effector 21 is positioned directly in front of the substrate W which is located relatively high above, while in the example in Figure 19, the end effector 21 is positioned directly in front of the substrate W which is located relatively low below. The sensor lifting drive unit 34 moves the sensor 30 to a height position corresponding to the reference position for each substrate W. For this reason, the sensor 30 shown in Figure 18 is positioned higher than the sensor 30 shown in Figure 19.

[0131] The sensor lifting drive unit 34 allows the distance between the sensor 30 and the end effector 21 to be kept within a certain range. In other words, the first light receiving unit 32A and the second light receiving unit 32B can each be made to follow the end effector 21. Therefore, the range of variation in the incident position of the measurement light L1 in each of the first light receiving unit 32A and the second light receiving unit 32B can be narrowed compared to the fifth example. Since the tip can be made to follow the end effector located in the immediate front position, smaller first light receiving unit 32A and smaller second light receiving unit 32B can be used. Also, since the optical path of the first measurement light L11 from the first light emitting unit 31A to the first light receiving unit 32A is shortened, the sensor 30 (control unit 90) can detect the position of the first tip of the first long portion 211A with higher accuracy. The same applies to the second light emitting unit 31B and the second light receiving unit 32B. Note that the seventh example of the second embodiment can be applied to the sixth example of the second embodiment.

[0132] As described above, the substrate transport device 110 and the substrate transport method have been explained in detail, but the above explanation is illustrative in all respects, and this disclosure is not limited thereto. Furthermore, the various modifications described above can be applied in combination as long as they do not contradict each other. And it is understood that a number of modifications not illustrated can be conceivable without falling outside the scope of this disclosure.

[0133] For example, in the second embodiment, the second light-emitting unit 31B and the second light-receiving unit 32B may be omitted, and the first light-emitting unit 31A and the first light-receiving unit 32A may be provided instead. Conversely, the first light-emitting unit 31A and the first light-receiving unit 32A may be omitted, and the second light-emitting unit 31B and the second light-receiving unit 32B may be provided instead.

[0134] Furthermore, although the substrate housing C in the above example is a portable housing, it is not necessarily limited to this. The substrate housing C may also be a stationary housing (shelf) set up on the substrate processing device 100.

[0135] This disclosure includes the following aspects:

[0136] The first embodiment is a substrate transport device comprising: a transport unit that includes an end effector and moves the end effector into the interior of a substrate container from the tip of the end effector to transport substrates into and out of the substrate container; a light-emitting unit that outputs measuring light toward the tip of the end effector located immediately before it enters the substrate container; and a light-receiving unit that receives the measuring light from the light-emitting unit, and a sensor that detects the position of the tip of the end effector based on the measuring light received by the light-receiving unit.

[0137] A second embodiment is a substrate transport apparatus according to the first embodiment, comprising a control unit for controlling the transport unit, wherein the control unit performs vibration reduction processing to reduce the vibration of the end effector when the amount of positional fluctuation of the end effector obtained based on the measurement light received by the light receiving unit is greater than a predetermined fluctuation reference value.

[0138] A third embodiment is a substrate transport device according to the second embodiment, wherein the control unit does not drive the transport unit as a vibration reduction process until the amount of position fluctuation becomes less than the fluctuation reference value.

[0139] A fourth embodiment is a substrate transport device according to any one of the first to third embodiments, comprising a control unit for controlling the transport unit, wherein the control unit controls the transport unit so that the position of the end effector obtained based on the measurement light received by the light receiving unit falls within a predetermined range.

[0140] The fifth embodiment is a substrate transport apparatus according to any one of the first to fourth embodiments, wherein the light-emitting unit and the light-receiving unit are provided laterally with respect to the end effector located in the immediate front position.

[0141] A sixth embodiment is a substrate transport apparatus according to the fifth embodiment, wherein the light-emitting unit and the light-receiving unit are provided on opposite sides of the end effector located directly in front of the end effector, the light-emitting unit outputs the measurement light which is wider than the thickness of the end effector, and the light-receiving unit receives the measurement light which has passed outside the end effector.

[0142] The seventh embodiment is a substrate transport apparatus according to the fifth embodiment, wherein the light-emitting unit and the light-receiving unit are provided on the same side of the end effector located directly in front of the end effector, the light-emitting unit outputs the measurement light which is wider than the thickness of the end effector, and the light-receiving unit receives the measurement light which has been reflected by the end effector.

[0143] The eighth aspect is a substrate transport device according to any one of the fourth to seventh aspects, wherein a plurality of substrates are housed in a substrate container arranged vertically, the measuring light is output from the light-emitting surface of the light-emitting unit and received by the light-receiving surface of the light-receiving unit, the upper end of the light-emitting surface and the upper end of the light-receiving surface are above the uppermost substrate among the plurality of substrates, and the lower end of the light-emitting surface and the lower end of the light-receiving surface are below the lowermost substrate among the plurality of substrates.

[0144] The ninth embodiment is a substrate transport device according to any one of the fourth to seventh embodiments, wherein a plurality of substrates are housed in the substrate housing in a vertically aligned manner, and a plurality of light-emitting units and a plurality of light-receiving units are provided in a vertically aligned manner.

[0145] The tenth embodiment is a substrate transport apparatus according to any one of the first to third embodiments, wherein the light-emitting unit and the light-receiving unit are provided on the same side in a vertical direction with respect to the tip of the end effector located in the immediate front position, and the light-receiving unit receives the measurement light reflected by the end effector.

[0146] The eleventh embodiment is a substrate transport apparatus according to the tenth embodiment, wherein the light-emitting unit and the light-receiving unit are provided below the tip of the end effector located in the immediate front position.

[0147] The twelfth embodiment is a substrate transport device according to any one of the first to eleventh embodiments, wherein a plurality of substrates are housed in the substrate container, and the device further comprises a sensor lifting drive unit that raises and lowers the light-emitting unit and the light-receiving unit according to the position of the substrates to be loaded and unloaded by the end effector.

[0148] The thirteenth embodiment is a substrate transport device according to any one of the first to twelfth embodiments, wherein the end effector has a first elongated portion, a second elongated portion spaced apart from the first elongated portion, and a connecting portion connecting the base ends of the first elongated portion and the second elongated portion, and the sensor includes a first light-emitting unit that outputs a first measurement light toward the first tip of the first elongated portion, a first light-receiving unit that receives the first measurement light, a second light-emitting unit that outputs a second measurement light toward the second tip of the second elongated portion, and a second light-receiving unit that receives the second measurement light.

[0149] The 14th embodiment is a substrate transport apparatus according to the 13th embodiment, comprising a sensor movement drive unit that moves a first inner optical unit, which is one of the first light-emitting unit and the first light-receiving unit, between a first measurement position and a first standby position, and moves a second inner optical unit, which is one of the second light-emitting unit and the second light-receiving unit, between a second measurement position and a second standby position, wherein the first measurement position is a position between the first elongated portion and the second elongated portion of the end effector located in the immediate forward position, the first elongated portion of the end effector located in the immediate forward position is located between the first outer optical unit, which is the other of the first light-emitting unit and the first light-receiving unit, and the first inner optical unit located in the first measurement position, and the first light-emitting unit has a first measurement light wider than the thickness of the first tip portion The first light receiving unit outputs the first measurement light that has passed outside the first tip, the first standby position is a position that avoids the movement path of the end effector, the second measurement position is a position between the first and second long portions of the end effector located in the immediate forward position, the second long portion of the end effector located in the immediate forward position is located between the second outer optical unit, which is the other of the second light emitting unit and the second light receiving unit, and the second inner optical unit located in the second measurement position, the second light emitting unit outputs the second measurement light which is wider than the thickness of the second tip, the second light receiving unit receives the second measurement light that has passed outside the second tip, and the second standby position is a position that avoids the movement path of the end effector.

[0150] The 15th embodiment is a substrate transport apparatus according to the 13th embodiment, wherein the first light-emitting unit and the first light-receiving unit are provided on the side opposite to the second long portion with respect to the first long portion, and the first light-receiving unit receives the first measurement light reflected at the first tip, and the second light-emitting unit and the second light-receiving unit are provided on the side opposite to the first long portion with respect to the second long portion, and the second light-receiving unit receives the second measurement light reflected at the second tip.

[0151] The sixteenth embodiment is a substrate transport apparatus according to any one of the thirteenth to fifteenth embodiments, wherein the wavelength of the first measurement light and the wavelength of the second measurement light are different from each other.

[0152] The 17th aspect is a substrate transport method comprising the steps of moving the end effector of a transport unit toward a substrate container containing a substrate, and emitting a measurement light from a light-emitting unit toward the tip of the end effector located immediately in front of the substrate container, and detecting the position of the tip based on the measurement light received by a light-receiving unit.

[0153] According to the first and seventeenth embodiments, the position of the tip of the end effector is detected. This makes it possible to determine with higher accuracy whether or not the tip of the end effector will collide with the substrate. In other words, the first embodiment contributes to avoiding collisions between the end effector and the substrate.

[0154] According to the second embodiment, the control unit performs vibration reduction processing, which further reduces the possibility of collision between the end effector and the substrate.

[0155] According to the third embodiment, vibration of the end effector can be reduced with simple control.

[0156] According to the fourth embodiment, the possibility of collision between the end effector and the substrate can be further reduced.

[0157] According to the fifth embodiment, since the light-emitting unit and the light-receiving unit are provided on the side of the end effector, the vertical position of the tip of the end effector can be detected with high accuracy.

[0158] According to the sixth embodiment, the position of the tip of the end effector can be detected on average.

[0159] According to the seventh embodiment, the position of the part of the end effector tip that reflects the measurement light can be detected.

[0160] According to the eighth aspect, the light-emitting unit can output measurement light to the tip of the end effector whenever the first transport unit picks up any substrate W. Therefore, the sensor can detect the position of the tip of the end effector.

[0161] According to the ninth aspect, the required precision for mounting the light-emitting unit and the light-receiving unit can be reduced.

[0162] According to the tenth embodiment, the position of the tip of the end effector that reflects the measurement light can be detected.

[0163] According to the eleventh embodiment, regardless of whether the end effector supports the substrate or not, the light-emitting unit can output measurement light to the lower surface of the end effector, and the light-receiving unit can receive the measurement light reflected from the lower surface of the end effector.

[0164] According to the twelfth embodiment, since the light-emitting unit and the light-receiving unit can be made to follow the end effector located directly in front of them, the position of the end effector can be detected more appropriately.

[0165] According to the 13th aspect, the position of the first tip of the first elongated portion and the position of the second tip of the second elongated portion can be obtained individually.

[0166] According to the 14th embodiment, the sensor can detect the position of the first tip of the first elongated portion when the first inner optical unit is in a first measurement position, and can detect the position of the second tip of the second elongated portion when the second inner optical unit is in a second measurement position. Furthermore, the end effector can enter the inside of the substrate housing when the first inner optical unit and the second inner optical unit are in a first standby position and a second standby position, respectively.

[0167] According to the 15th embodiment, the first light-emitting unit, the first light-receiving unit, the second light-emitting unit, and the second light-receiving unit are arranged to avoid the movement path of the end effector, so that the movement of the end effector is not obstructed.

[0168] According to the 16th aspect, noise can be reduced. [Explanation of Symbols]

[0169] 110 Substrate transport device 20. Transport Unit (First Processing Unit) 21 End Effectors 211A 1st long part 211B 2nd long part 212 Connecting part 30 sensors 31 Light-emitting part 31A First light-emitting section 31B Second light-emitting section 31s luminescent surface 32 Light receiving part 32A 1st light receiving section 32B Second light-emitting section 32s light receiving surface 33 Sensor movement drive unit 34 Sensor Lifting Drive Unit 90 Control Unit C board housing L1 Measurement light L11 First measurement light L12 2nd measurement light

Claims

1. A transport unit including an end effector, which moves the end effector into the inside of the substrate container from the tip of the end effector and loads and unloads substrates into and out of the substrate container, A light-emitting unit that outputs measurement light toward the tip of the end effector located immediately before it enters the substrate housing, and a light-receiving unit that receives the measurement light from the light-emitting unit, and a sensor that detects the position of the tip of the end effector based on the measurement light received by the light-receiving unit. A substrate transport device equipped with the following features.

2. A substrate transport apparatus according to claim 1, The system includes a control unit that controls the transport unit, A substrate transport device in which the control unit performs vibration reduction processing to reduce the vibration of the end effector when the amount of positional fluctuation of the end effector obtained based on the measurement light received by the light receiving unit is greater than a predetermined fluctuation reference value.

3. A substrate transport apparatus according to claim 2, The control unit, as part of the vibration reduction process, does not drive the transport unit until the amount of positional fluctuation falls below the fluctuation reference value, in this substrate transport device.

4. A substrate transport device according to any one of claims 1 to 3, The system includes a control unit that controls the transport unit, A substrate transport device in which the control unit controls the transport unit so that the position of the end effector, obtained based on the measurement light received by the light receiving unit, falls within a predetermined range.

5. A substrate transport device according to any one of claims 1 to 3, A substrate transport device wherein the light-emitting unit and the light-receiving unit are provided laterally to the end effector located directly in front of the substrate transport device.

6. A substrate transport apparatus according to claim 5, The light-emitting unit and the light-receiving unit are provided on opposite sides of the end effector located in the immediate vicinity. The light-emitting unit outputs the measurement light which is wider than the thickness of the end effector. The light-receiving unit is a substrate transport device that receives the measurement light that has passed outside the end effector.

7. A substrate transport apparatus according to claim 5, The light-emitting unit and the light-receiving unit are provided on the same side relative to the end effector located in the immediate vicinity. The light-emitting unit outputs the measurement light which is wider than the thickness of the end effector. The light receiving unit is a substrate transport device that receives the measurement light reflected by the end effector.

8. A substrate transport apparatus according to claim 4, The substrate housing houses a plurality of substrates arranged vertically. The measurement light is output from the light-emitting surface of the light-emitting unit and received by the light-receiving surface of the light-receiving unit. The upper end of the light-emitting surface and the upper end of the light-receiving surface are located above the uppermost substrate among the plurality of substrates. A substrate transport device wherein the lower end of the light-emitting surface and the lower end of the light-receiving surface are located below the lowest substrate among the plurality of substrates.

9. A substrate transport apparatus according to claim 4, The substrate housing houses a plurality of substrates arranged vertically. A substrate transport device in which a plurality of the light-emitting units and a plurality of light-receiving units are arranged in the vertical direction.

10. A substrate transport device according to any one of claims 1 to 3, The light-emitting portion and the light-receiving portion are provided on the same side in the vertical direction with respect to the tip portion of the end effector located in the immediate vicinity. The light receiving unit is a substrate transport device that receives the measurement light reflected by the end effector.

11. A substrate transport apparatus according to claim 10, A substrate transport device wherein the light-emitting unit and the light-receiving unit are provided below the tip of the end effector located in the immediate front position.

12. A substrate transport device according to any one of claims 1 to 3, The aforementioned substrate housing contains a plurality of the aforementioned substrates, A substrate transport device further comprising a sensor lifting drive unit that raises and lowers the light-emitting unit and the light-receiving unit according to the position of the substrate to be transported in and out of the end effector.

13. A substrate transport device according to any one of claims 1 to 3, The aforementioned end effector is, The first long section and, A second long portion is provided at a distance from the first long portion, A connecting portion that connects the base ends of the first and second long portions. It has, The aforementioned sensor is The first light-emitting unit emits the first measurement light toward the first tip of the first elongated portion, The first light receiving unit that receives the first measurement light, The second light-emitting unit outputs the second measurement light toward the second tip of the second elongated portion, The second light receiving unit that receives the second measurement light and A substrate transport device, including a substrate transport device.

14. A substrate transport apparatus according to claim 13, The sensor movement drive unit moves the first inner optical unit, which is one of the first light-emitting unit and the first light-receiving unit, between a first measurement position and a first standby position, and moves the second inner optical unit, which is one of the second light-emitting unit and the second light-receiving unit, between a second measurement position and a second standby position. The first measurement position is located between the first and second long portions of the end effector at the immediate preceding position. The first long portion of the end effector located in the immediate vicinity is positioned between the first outer optical section, which is the other of the first light-emitting section and the first light-receiving section, and the first inner optical section located at the first measurement position. The first light-emitting unit outputs the first measurement light which is wider than the thickness of the first tip, The first light-receiving unit receives the first measurement light that has passed outside the first tip portion, The first standby position is a position that avoids the movement path of the end effector. The second measurement position is located between the first and second long portions of the end effector at the immediate preceding position. The second long portion of the end effector located in the immediate vicinity is positioned between the second outer optical section, which is the other of the second light-emitting section and the second light-receiving section, and the second inner optical section located at the second measurement position. The second light-emitting unit outputs the second measurement light which is wider than the thickness of the second tip, The second light-receiving unit receives the second measurement light that has passed outside the second tip, The substrate transport device wherein the second standby position is a position that avoids the movement path of the end effector.

15. A substrate transport apparatus according to claim 13, The first light-emitting portion and the first light-receiving portion are provided on the side opposite to the second long portion with respect to the first long portion. The first light receiving unit receives the first measurement light reflected at the first tip, The second light-emitting portion and the second light-receiving portion are provided on the side opposite to the first long portion with respect to the second long portion. The substrate transport device includes a second light-receiving unit that receives the second measurement light reflected from the second tip.

16. A substrate transport apparatus according to claim 13, A substrate transport device wherein the wavelength of the first measurement light and the wavelength of the second measurement light are different from each other.

17. The process involves moving the end effector of the transport unit toward the board holder containing the board, A step of outputting measurement light from the light-emitting unit toward the tip of the end effector located immediately in front of the substrate housing, and detecting the position of the tip based on the measurement light received by the light-receiving unit. A substrate transport method comprising the above.

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