Substrate transport apparatus and substrate transport method

Abstract

This technology contributes to reducing vibration in end effectors. [Solution] The substrate transport device comprises an end effector 21, a transport drive unit 22, a vibration sensor 27, and a vibrator 28. The end effector 21 supports the substrate. The transport drive unit 22 includes a lifting drive unit 24 for raising and lowering the end effector 21, and a reciprocating drive unit 23 for moving the end effector 21 in the forward and backward directions relative to the substrate container. The vibration sensor 27 detects vibrations at the tip of the end effector 21. The vibrator 28 is provided separately from the transport drive unit 22. The vibrator 28 vibrates the end effector 21 vertically based on the detection by the vibration sensor 27, thereby reducing vibrations at the tip of the end effector 21 caused by the drive of the transport drive unit 22.

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 proposed (Patent Document 1). In Patent Document 1, the substrate transfer device includes a hand that holds a substrate, an arm connected to the hand, and a lifting shaft connected to the arm. The lifting shaft raises and lowers the arm and the hand. By driving the arm, the hand moves in the horizontal direction.

[0003] The substrate transfer device is provided with a control system for suppressing the vibration of the hand, and the control system is provided with vibration detection means for detecting the vibration of the hand. The vibration detection means is provided at the base of the hand. In Patent Document 1, when the arm extends immediately before delivering the substrate, the lifting shaft vibrates the arm in the vertical direction so as to reduce the vibration detected by the vibration detection means.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] The lifting shaft needs to raise and lower the substrate within a lifting range in which the substrate can be transferred. For example, it is necessary to raise the hand within a lifting range such that any substrate in the cassette can be lifted by the hand. Such a lifting range for conveyance is larger than the amplitude of the vibration generated in the hand. Therefore, a relatively large-sized drive unit is selected for the lifting shaft. It is difficult to sufficiently reduce the fine vibration generated in the hand by such a large-sized lifting shaft.

[0006] In the following, the part that supports or holds the circuit board will be referred to as the end effector.

[0007] This disclosure aims to provide a technology that contributes to reducing vibration in end effectors. [Means for solving the problem]

[0008] The substrate transport device is a substrate transport device for transporting substrates into and out of a substrate container, and comprises an end effector that supports the substrate, a transport drive unit including a lifting drive unit for raising and lowering the end effector, and a reciprocating drive unit for moving the end effector in the forward and backward directions relative to the substrate container, a vibration sensor for detecting vibration of the tip of the end effector, and a vibrator provided separately from the transport drive unit that vibrates the end effector in the vertical direction based on the detection by the vibration sensor to reduce vibration of the tip of the end effector caused by the drive of the transport drive unit.

[0009] The substrate transport method is a substrate transport method for loading and unloading substrates into and out of a substrate container, wherein a transport drive unit moves an end effector toward the substrate container, a vibration sensor detects vibrations at the tip of the end effector, and a vibrator provided separately from the transport drive unit vibrates the end effector vertically based on the detection by the vibration sensor, thereby reducing vibrations at the tip of the end effector caused by the drive of the transport drive unit. [Effects of the Invention]

[0010] The vibrator does not need to have a substrate transport function. Therefore, a drive unit suitable for reducing vibration at the tip of the end effector can be used as the vibrator. In other words, the substrate transport device and substrate processing method contribute to reducing vibration of the end effector. [Brief explanation of the drawing]

[0011] [Figure 1]This is a schematic plan view showing an example of the configuration of a substrate processing apparatus, including a first transport unit 20, which is an example of a substrate transport apparatus according to an 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 flowchart shows an example of the operation of the first transport unit. [Figure 6] This flowchart shows an example of the operation of the first transport unit. [Figure 7] This is a schematic plan view illustrating an example of an end-effector configuration. [Figure 8] This diagram schematically shows another example of the configuration of the first transport unit. [Modes for carrying out the invention]

[0012] 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.

[0013] 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.

[0014] 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.

[0015] 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.

[0016] <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 first transport unit 20, which is an example of a substrate transport device according to an embodiment. The substrate processing apparatus 100 is a single-wafer processing apparatus that processes substrates W one at a time.

[0017] The substrate W is, for example, a semiconductor wafer, a substrate for a liquid crystal display, a substrate for an organic EL (Electroluminescence), a substrate for an FPD (Flat Panel Display), a substrate for an optical display, a substrate for a magnetic disk, a substrate for an optical disk, a substrate for a magneto-optical disk, a substrate for a photomask, or a substrate for a solar cell. The substrate W has a thin flat plate shape. Hereinafter, 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, not less than about 0.5 mm and not more than about 3 mm.

[0018] In the example of FIG. 1, the substrate processing apparatus 100 includes an index block 110, a processing block 120, and a control unit 90. The processing block 120 is a part mainly for processing the substrate W. In the example of FIG. 1, the index block 110 is a part mainly for transferring the substrate W between the outside of the substrate processing apparatus 100 and the processing block 120.

[0019] The index block 110 includes a first transfer unit 20. As shown in FIG. 1, a load port \alpha may be provided in the index block 110. A substrate container C carried in from the outside is placed on the load port 10. That is, the load port 10 includes a mounting table on which the substrate container C is placed. A holding mechanism (not shown) for holding the substrate container C may be provided on the mounting table. In the example of FIG. 1, a plurality of load ports 10 are arranged along a horizontal arrangement direction Dy. A plurality of substrates W are accommodated in the substrate container C. As an example, the plurality of substrates W are accommodated in the substrate container C in a state of being arranged at intervals in the vertical direction. A specific configuration example of the substrate container C will be described in detail later.

[0020] 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.

[0021] 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.

[0022] 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.

[0023] 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.

[0024] 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.

[0025] The control unit 90 comprehensively controls the substrate processing apparatus 100. More specifically, the control unit 90 controls the first transport unit 20, 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.

[0026] 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, vibration data D1 is stored in the storage unit 94. The vibration data D1 will be described in detail later.

[0027] <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.

[0028] 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.

[0029] 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.

[0030] 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 (hereinafter referred to as "substrate spacing") 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 substrate spacing increases the risk of the end effector 21 colliding with the substrate W.

[0031] <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, a transport drive unit 22, a vibration sensor 27, and a vibrator 28.

[0032] <End effector> 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 with its thickness direction 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 with its longitudinal direction aligned with the horizontal direction. The second elongated portion 211B has an elongated plate-like shape and is installed with its longitudinal direction 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 (for example, aluminum or carbon). The connecting portion 212 corresponds to the base end of the end effector 21.

[0033] <Transport drive unit> 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.

[0034] 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 or a cam mechanism. The vertical movement range (i.e., lifting range) of the end effector 21 by the lifting drive unit 24 can be set to, for example, a range from the inner bottom surface to the ceiling surface of the substrate housing C. This allows the lifting drive unit 24 to raise and lower the end effector 21 to a height position corresponding to any substrate W in the substrate housing C. As a specific example, the lifting range may be set to 100 mm or more, 200 mm or more, or 300 mm or more.

[0035] 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 with the vertical direction. The rotary drive unit 25 rotates the end effector 21 between a first rotation position where the tip of the end effector 21 faces the substrate housing C side and a second 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. With the end effector 21 in the first rotation position, the forward / backward drive unit 23 can move the end effector 21 in the forward / backward direction relative to the substrate housing C. The forward / backward direction is the horizontal direction in which the end effector 21 can enter the substrate housing C.

[0036] 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 to be 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 indexer block 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.

[0037] When the transport drive unit 22 moves the end effector 21, vibration occurs in the end effector 21. In other words, vibration occurs in the end effector 21 due to the drive of the transport drive unit 22. For example, the end effector 21 vibrates so that the tip of the end effector 21 moves back and forth vertically relative to the base of the end effector 21. If the amplitude of the swing of the tip of the end effector 21 due to this vibration becomes large, the end effector 21 may collide with the substrate W when it enters the substrate housing C.

[0038] <Sensor> The vibration sensor 27 is a sensor for detecting vibrations generated in the end effector 21. The vibration sensor 27 detects, for example, vertical vibrations generated in the end effector 21. The vibration sensor 27 outputs an electrical signal indicating the detection result to the control unit 90. The vibration sensor 27 includes, for example, an acceleration sensor. The acceleration sensor detects the acceleration generated in itself and outputs an electrical signal indicating the detection result to the control unit 90. For example, the acceleration sensor detects the vertical component of the acceleration generated in itself. The acceleration sensor may be, for example, a strain gauge type, a capacitive type, or a piezoelectric type acceleration sensor. In the example in Figure 4, the vibration sensor 27 is provided at the tip of the end effector 21. Therefore, the vibration sensor 27 detects the acceleration (vertical component) at the tip of the end effector 21.

[0039] The tip portion on which the vibration sensor 27 is provided may be a part of the end effector 21 that is one-quarter of the length of the end effector 21 from the tip, or a part of the end effector 21 that is one-eighth of the length. For example, the tip portion may be a part of the end effector 21 that is within 10 mm from the tip, a part of the end effector 21 that is within 5 mm or less, or a part of the end effector 21 that is within 3 mm. The vibration sensor 27 may be provided at the tip of the end effector 21. In the example in Figure 1, the end effector 21 is provided with a first long portion 211A and a second long portion 211B. The vibration sensor 27 may be provided at the tip of the first long portion 211A, or at the tip of the second long portion 211B.

[0040] The control unit 90 obtains time-series data of the position of the vibration sensor 27, that is, the position of the tip of the end effector 21, by performing time integration on the time-series data of acceleration input from the vibration sensor 27. This time-series data represents the vibration of the tip of the end effector 21. The functional unit of the control unit 90 that generates the time-series data of position can be said to belong to the vibration sensor 27. However, this functional unit does not necessarily have to be implemented in the control unit 90. If the control unit is built into the vibration sensor 27, this functional unit may be implemented in the control unit.

[0041] <Vibrator 28> The vibrator 28 vibrates the end effector 21 vertically, reducing vibrations at the tip of the end effector 21 caused by the drive of the transport drive unit 22. In the example shown in Figure 4, the vibrator 28 is located between the base end of the end effector 21 and the transport drive unit 22. Specifically, the vibrator 28 is located between the connecting portion 212 of the end effector 21 and the tip of the joint of the arm 231. The vibrator 28 causes the base end of the end effector 21 to reciprocate vertically relative to the arm 231. This reciprocating movement allows the vibrator 28 to impart vertical vibrations to the end effector 21. The vibrator 28 imparts vibrations to the end effector 21 in opposite phase to the vibrations caused by the drive of the transport drive unit 22. As a result, vibrations caused by the transport drive unit 22 are canceled out by vibrations caused by the vibrator 28, reducing vibrations at the tip of the end effector 21. The vibrator 28 is connected to the control unit 90 and is driven by a drive signal generated by the control unit 90.

[0042] Incidentally, since the vibrator 28 reciprocates along the vertical direction of the base end of the end effector 21, its function in terms of direction of movement is the same as that of the lifting drive unit 24. However, the resolution of the vibrator 28 (hereinafter referred to as position resolution) is smaller than that of the lifting drive unit 24. Position resolution is an indicator of the reproducibility of positioning and shows the variation in the actual position due to control at the target position. For example, the position resolution of the vibrator 28 may be 1 μm or less, 0.5 μm or less, 0.1 μm or less, or 0.01 μm or less. As a result, the vibrator 28 can apply more precise vibrations to the end effector 21, and vibrations of the end effector 21 caused by the transport drive unit 22 can be reduced with higher precision.

[0043] The vertical movement range of the end effector 21 due to the vibrator 28 (i.e., the amplitude range of vibration of the vibrator 28) is narrower than the vertical movement range of the end effector 21 due to the lifting drive unit 24. The movement range of the end effector 21 due to the vibrator 28 may be 10 mm or less, 5 mm or less, or 1 mm or less. This allows for the use of a smaller vibrator 28. As a result, the vibrator 28 can be made lighter, and the increase in vibration of the end effector 21 caused by the weight of the vibrator 28 can be suppressed. Also, if the vibrator 28 is small, the backlash of the vibrator 28 can be made smaller than the backlash of the lifting drive unit 24. This allows the vibrator 28 to apply more precise vibrations to the end effector 21, and the vibration of the end effector 21 caused by the transport drive unit 22 can be reduced with higher precision.

[0044] For example, the vibrator 28 includes a piezo actuator. The piezo actuator includes, for example, a piezo motor (or ultrasonic motor). The piezo motor includes, for example, a stator having a piezoelectric element and a moving element that moves due to friction associated with a small displacement of the stator. The moving element may be a stator that rotates around a predetermined axis of rotation. The vibrator 28 includes a power transmission unit that converts the rotational motion of the piezo motor into vertical motion. The power transmission unit may be, for example, an eccentric mechanism or a Z-axis stage mechanism.

[0045] <Operation of the substrate transport device> Figures 5 and 6 are flowcharts illustrating an example of the operation of the first transport unit 20. This operation can be achieved by the control unit 90 controlling the transport drive unit 22, vibration sensor 27, and vibrator 28 of the first transport unit 20. Figure 5 shows the pre-vibration acquisition operation. The pre-vibration acquisition operation is the operation of acquiring vibration data D1 of the end effector 21 generated by the drive of the transport drive unit 22 while the vibrator 28 is not vibrating. Figure 6 shows the substrate W unloading operation. Below, an example of the pre-vibration acquisition operation will be described, followed by an example of the unloading operation.

[0046] The pre-vibration acquisition operation is performed in advance, for example, before loading or unloading the substrate W. For example, the pre-vibration acquisition operation is performed when the substrate processing device 100 is installed. First, the control unit 90 instructs the transport drive unit 22 to move the end effector 21 to a position facing the substrate container C (step S11). Specifically, the control unit 90 instructs the movement drive unit 26 to move the end effector 21 along the arrangement direction Dy, the rotation drive unit 25 to rotate the end effector 21 to a first rotation position where the tip of the end effector 21 faces the substrate container C, and the lifting drive unit 24 to raise or lower the end effector 21 to a height position from which the substrate W can be removed.

[0047] Next, while the vibration sensor 27 detects vibrations at the tip of the end effector 21, the control unit 90 instructs the forward / backward drive unit 23 to move the end effector 21 horizontally toward the substrate housing C (step S12). The control unit 90 instructs the forward / backward drive unit 23 to move the end effector 21 to a position directly below the substrate W to be removed. During this movement, the vibration sensor 27 continues to detect vibrations. If the vibration sensor 27 includes an acceleration sensor, the vibration sensor 27 continues to detect the vertical component of acceleration generated at the tip of the end effector 21. In other words, the vibration sensor 27 generates time-series data of acceleration. The vibration sensor 27 (control unit 90) integrates the time-series data of acceleration twice over time to generate time-series data of position. The time-series data of position indicates the vibrations at the tip of the end effector 21.

[0048] The vibration sensor 27 begins detecting vibrations at least before the tip of the end effector 21 enters the board housing C. In other words, the vibration sensor 27 begins detecting vibrations before the tip of the end effector 21 enters the board housing C. As a specific example, the vibration sensor 27 begins detecting vibrations when the reciprocating drive unit 23 starts moving the end effector 21. The vibration sensor 27 may continue detecting vibrations until the end effector 21 stops directly below the board W. Alternatively, the vibration sensor 27 may continue detecting vibrations until the tip of the end effector 21 enters the board housing C. In other words, the vibration sensor 27 may stop detecting vibrations after the tip of the end effector 21 enters the board housing C.

[0049] Next, the control unit 90 stores the vibration data D1, which represents the vibration of the end effector 21 acquired in step S12, in the storage unit 94 (step S13). The vibration data D1 may be time-series data of acceleration, time-series data of position, or, as described later, frequency component data that represents the frequency components of vibration. Steps S12 and S13 may be performed in parallel.

[0050] Figure 7 is a schematic plan view showing an example of the configuration of the end effector 21. In Figure 7, the total length L1 of the end effector 21 and the lengths L2 of the first long section 211A and the second long section 211B are shown. Here, the lengths L2 of the first long section 211A and the second long section 211B are assumed to be equal.

[0051] The tip of the end effector 21 vibrates, for example, accompanied by the bending of the end effector 21. Specifically, the end effector 21 bends so that its tip is above or below its base. Therefore, the vibration of the tip of the end effector 21 includes multiple frequency components corresponding to the lengths of each part. For example, the vibration of the tip of the end effector 21 includes a first frequency component corresponding to the total length L1 of the end effector 21 and a second frequency component corresponding to the lengths L2 of the first long section 211A and the second long section 211B. Since the total length L1 of the end effector 21 is relatively long, the frequency of the first frequency component is relatively low, and the magnitude (i.e., amplitude) of the first frequency component is large. On the other hand, since the lengths L2 of the first long section 211A and the second long section 211B are shorter than the total length L1, the frequency of the second frequency component is higher than the frequency of the first frequency component, and the magnitude (i.e., amplitude) of the second frequency component is smaller than the magnitude of the first frequency component. In addition to the first and second frequency components, the vibration may contain various other frequency components.

[0052] The control unit 90 may perform a Fourier transform on the time-series position data to generate frequency component data. The control unit 90 may also perform a Fast Fourier Transform. The frequency component data shows the relationship between the frequency and magnitude of each frequency component included in the time-series position data. The control unit 90 may store this frequency component data as vibration data D1 in the storage unit 94.

[0053] As described above, vibration data D1 is stored in the storage unit 94 by the pre-vibration acquisition operation. This vibration data D1 indicates the vibration of the tip of the end effector 21 during the period when the end effector 21 is moving along the forward and backward direction toward the substrate housing C.

[0054] Next, an example of the unloading operation will be described with reference to Figure 6. First, similar to step S11, the control unit 90 instructs the transport drive unit 22 to move the end effector 21 to a position facing the substrate container C (step S21). Here, the control unit 90 instructs the lifting drive unit 24 to raise and lower the end effector 21 to a height position corresponding to the substrate W to be unloaded from the substrate container C.

[0055] Next, the control unit 90 instructs the first transport unit 20 to move the end effector 21 horizontally toward the substrate holder C while reducing vibration at the tip of the end effector 21, and to stop it directly beneath the substrate W (step S22). Here, the control unit 90 controls the reciprocating drive unit 23 to move at the same speed (target value) as the movement speed (target value) of the end effector 21 in step S11. In this case, the reciprocating drive unit 23 moves the end effector 21 toward the substrate holder C at a speed approximately the same as the movement speed of the end effector 21 in step S11.

[0056] Furthermore, in step S21, the vibration sensor 27 detects vibration at the tip of the end effector 21. The vibration sensor 27 begins detecting vibration at least before the tip of the end effector 21 enters the substrate housing C. As a specific example, the vibration sensor 27 begins detecting vibration as soon as the reciprocating drive unit 23 starts moving the end effector 21.

[0057] The control unit 90 vibrates the vibrator 28 with a frequency and amplitude based on the vibration data D1, and in the opposite phase to the phase of the vibration detected by the vibration sensor 27. Specifically, first, the control unit 90 reads the vibration data D1 from the storage unit 94. Here, it is assumed that the vibration data D1 includes frequency components. The control unit 90 identifies one or more target frequency components that include the frequency component with the largest amplitude among the multiple frequency components included in the vibration data D1. Based on the vibration detected by the vibration sensor 27, the control unit 90 determines the phase of the vibration of the end effector 21 (for example, the phase of each frequency component) and vibrates the vibrator 28 with a vibration pattern that includes the frequency and the opposite phase of the target frequency component.

[0058] The vibrations applied to the end effector 21 by the vibrator 28 are canceled out by the vibrations applied to the end effector 21 by the drive of the transport drive unit 22. In other words, the amplitude of vibration at the tip of the end effector 21 can be reduced. Conversely, the control unit 90 vibrates the vibrator 28 at a magnitude (for example, the amplitude of each target frequency component of the vibration pattern) that reduces the amplitude of vibration at the tip of the end effector 21. As a result, the end effector 21 enters the inside of the substrate housing C with reduced vibration at its tip. In other words, the end effector 21 enters the area of ​​the gap between the substrates W with reduced vibration at its tip. Therefore, the possibility of collision between the end effector 21 and the substrates W inside the substrate housing C can be appropriately reduced.

[0059] The control unit 90 causes the vibrator 28 to start vibrating at least before the tip of the end effector 21 enters the substrate housing C. In other words, the control unit 90 causes the vibrator 28 to start vibrating while the tip of the end effector 21 has not yet entered the substrate housing C. As a specific example, the control unit 90 starts vibrating the vibrator 28 immediately after vibration detection by the vibration sensor 27. The control unit 90 may continue to vibrate the vibrator 28 until the end effector 21 stops directly below the substrate W. This allows the vibrator 28 to continue reducing the vibration of the end effector 21 caused by the transport drive unit 22 until the end effector 21 stops directly below the substrate W.

[0060] Next, the control unit 90 instructs the lifting drive unit 24 to raise the end effector 21, causing the end effector 21 to lift the substrate W (step S23). Next, the control unit 90 instructs the retraction drive unit 23 to retract the end effector 21 from the substrate housing C (step S24). As a result, the substrate W is removed from the substrate housing C.

[0061] As described above, in this embodiment, the vibrator 28, which is provided separately from the transport drive unit 22, vibrates the end effector 21, thereby reducing the vibration of the tip of the end effector 21 caused by the drive of the transport drive unit 22. In other words, the transport drive unit 22 does not need to have a vibration reduction function, and a drive unit suitable for transporting the substrate W can be used as the transport drive unit 22. Conversely, the vibrator 28 does not need to have a substrate W transport function, and a drive unit suitable for reducing vibration of the tip of the end effector 21 can be used as the vibrator 28.

[0062] In the example described above, the transducer 28 is one having a position resolution smaller than that of the lifting drive unit 24. Therefore, the transducer 28 can reduce the vibration of the end effector 21 with higher precision.

[0063] In the example described above, the vibrator 28 is one that has a narrower range of motion than the range of motion of the lifting drive unit 24. In other words, a smaller vibrator 28 is used. As a result, the vibrator 28 can be made lighter, and the vibration of the end effector 21 can be reduced with greater precision. In addition, the backlash that occurs in the small vibrator 28 is smaller than the backlash that occurs in the large lifting drive unit 24. As a result, the vibrator 28 can reduce the vibration of the end effector 21 with greater precision.

[0064] In the example described above, the transducer 28 includes a piezo actuator (specifically, a piezo motor or ultrasonic motor). Because the position resolution of the piezo actuator is very small, the transducer 28 can reduce the vibration of the end effector 21 with greater precision.

[0065] In the example described above, the vibrator 28 is located between the base end of the end effector 21 and the reciprocating drive unit 23. In other words, the vibrator 28 is located at the connection point between the base end of the end effector 21 and the reciprocating drive unit 23. The base end of the end effector 21 is located above the reciprocating drive unit 23, and the vibrator 28 is located below the base end of the end effector 21 and above the lifting drive unit 24. For example, the upper surface of the vibrator 28 is in contact with the lower surface of the connecting portion 212 of the end effector 21, and the lower surface of the vibrator 28 is in contact with the upper surface of the reciprocating drive unit 23 (specifically, the upper surface of the arm 231). To put it another way, the vibrator 28 is located closer to the tip of the end effector 21 than to the lifting drive unit 24. In other words, the vibrator 28 is located closer to the vibration reduction target (end effector 21). Therefore, the transducer 28 can reduce vibrations at the tip of the end effector 21 with higher precision and responsiveness.

[0066] In the example described above, the vibration sensor 27 is an acceleration sensor located at the tip of the end effector 21. Therefore, the vibration sensor 27 can directly detect vibrations at the tip of the end effector 21. Thus, the vibration sensor 27 can detect vibrations at the tip of the end effector 21 with higher accuracy.

[0067] In the example described above, vibration data D1 is stored in the storage unit 94 in advance, and the control unit 90 controls the vibrator 28 based on the vibration data D1. In other words, the control unit 90 vibrates the vibrator 28 in a predetermined vibration pattern. Therefore, the control unit 90 can control the vibrator 28 with simpler control.

[0068] The control unit 90 does not necessarily have to control the vibrator 28 with a predetermined vibration pattern. For example, the control unit 90 may use the vibration detected by the vibration sensor 27 to perform feedback control on the vibrator 28. Specifically, in step S22, the vibration sensor 27 detects vibration at predetermined intervals, and the control unit 90 determines the vibration pattern of the vibrator 28 at predetermined intervals based on the detection results of the vibration sensor 27, and vibrates the vibrator 28 with the determined vibration pattern. This also reduces vibration at the tip of the end effector 21.

[0069] <Another example> The indexer block 110 may be provided with a substrate sensor (not shown) for detecting the spacing between substrates in the substrate container C. The substrate sensor may be a mapping sensor provided at each load port 10 of the indexer block 110. Alternatively, the substrate sensor may be provided on the end effector 21. Figure 8 is a schematic diagram showing another example of the configuration of this first transport unit 20. In the example of Figure 8, the first transport unit 20 includes an optical sensor 29 as a substrate sensor. The optical sensor 29 is a sensor that detects substrates W in the substrate container C. For example, the optical sensor 29 is a camera. In the example of Figure 8, the optical sensor 29 is provided at the base end of the end effector 21. Specifically, the optical sensor 29 is provided on the upper surface of the connecting portion 212 of the end effector 21. The optical sensor 29 may also be provided near the connection portion with the arm 231 of the end effector 21.

[0070] Since the optical sensor 29 is located on the end effector 21, the optical sensor 29 moves together with the end effector 21. In other words, the transport drive unit 22 moves the end effector 21 and the optical sensor 29 together.

[0071] The optical sensor 29 captures an image of the area in front of the end effector 21 in the direction of movement and generates image data. Specifically, with the transport drive unit 22 moving the optical sensor 29 to a position facing the substrate holder C, the optical sensor 29 captures an image of the substrate holder C and generates image data. The optical sensor 29 outputs the image data to the control unit 90.

[0072] The lifting drive unit 24 lowers the optical sensor 29 from a first height position to a second height position, as described below, while the optical sensor 29 is capturing images. The first height position may be a position where the optical sensor 29 is directly in front of the uppermost substrate W in the substrate housing C, or a position above that position. The second height position may be a position where the optical sensor 29 is directly in front of the lowermost substrate W in the substrate housing C, or a position below that position. While the optical sensor 29 is being lowered by the lifting drive unit 24, it captures images of the substrate housing C at a predetermined frame rate and generates multiple image data. These multiple image data may correspond to frames of moving image data. Since the optical sensor 29 captures images of the substrate housing C while being lowered, images captured at the same height as each substrate W in the substrate housing C are included in any of the multiple image data. Alternatively, the lifting drive unit 24 may raise the optical sensor 29 from the second height position to the first height position while the optical sensor 29 captures images of the substrate housing C.

[0073] The control unit 90 detects the substrates W inside the substrate housing C by image processing of each captured image data. For example, the control unit 90 may detect the presence or absence of the substrate W based on captured image data including a front view of the substrate W, detect the shape of the top or bottom surface of the substrate W, or detect the shape of the gap between the substrate W and the substrate W directly below it.

[0074] The control unit 90 may set an allowable value for the amplitude of vibration at the tip of the end effector 21 based on the gap area between the substrates W. The control unit 90 may set a larger allowable value for vibration the wider the gap.

[0075] In step S22, the control unit 90 may control the vibrator 28 so that the vibration of the tip of the end effector 21 detected by the vibration sensor 27 falls below an allowable amplitude. This makes it possible to reduce the amplitude of the vibration of the end effector 21 to an allowable value corresponding to the gap area (spacing) between the substrates W.

[0076] As described above, the substrate transport apparatus (first transport unit 20) and the substrate transport method have been described in detail, but the above description 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.

[0077] This disclosure includes the following aspects:

[0078] The first embodiment is a substrate transport device for transporting substrates into and out of a substrate container, comprising: an end effector for supporting the substrate; a transport drive unit including a lifting drive unit for raising and lowering the end effector and a reciprocating drive unit for moving the end effector in the forward and backward directions relative to the substrate container; a vibration sensor for detecting vibration of the tip of the end effector; and a vibrator provided separately from the transport drive unit for vibrating the end effector in the vertical direction based on the detection by the vibration sensor to reduce vibration of the tip of the end effector caused by the drive of the transport drive unit.

[0079] A second embodiment is a substrate transport device according to the first embodiment, wherein the vibrator is provided between the base end of the end effector and the transport drive unit.

[0080] A third embodiment is a substrate transport device according to the first or second embodiment, wherein the vertical position resolution of the vibrator is smaller than the position resolution of the lifting drive unit.

[0081] A fourth embodiment is a substrate transport device according to any one of the first to third embodiments, wherein the amplitude range of the vertical vibration of the vibrator is narrower than the range of movement of the end effector by the lifting drive unit.

[0082] The fifth embodiment is a substrate transport device according to any one of the first to fourth embodiments, wherein the vibrator includes a piezo actuator.

[0083] The sixth embodiment is a substrate transport device according to any one of the first to fifth embodiments, wherein the vibration sensor includes an acceleration sensor provided at the tip of the end effector.

[0084] The seventh embodiment is a substrate transport device according to any one of the first to sixth embodiments, comprising a storage unit and a control unit, wherein the storage unit stores vibration data indicating the vibration of the end effector caused by the transport drive unit, and the control unit vibrates the vibrator at a frequency and amplitude based on the vibration data, and in the opposite phase to the phase of the vibration of the end effector detected by the vibration sensor.

[0085] The eighth aspect is a substrate transport apparatus according to the seventh aspect, wherein the control unit obtains the frequency components of the vibration of the end effector by Fourier transform and vibrates the vibrator based on the frequency components.

[0086] A ninth aspect is a substrate transport device according to the seventh aspect, further comprising a substrate sensor for detecting the area of ​​gaps between substrates in the substrate container, wherein the control unit sets an allowable amplitude for vibration of the tip of the end effector based on the area of ​​gaps between substrates detected by the substrate sensor, and controls the vibrator so that the vibration of the tip of the end effector detected by the vibration sensor falls below the allowable amplitude.

[0087] A tenth aspect is a substrate transport method, which involves transporting a substrate into and out of a substrate container, wherein a transport drive unit moves an end effector toward the substrate container, a vibration sensor detects vibrations at the tip of the end effector, and a vibrator provided separately from the transport drive unit vibrates the end effector vertically based on the detection by the vibration sensor, thereby reducing vibrations at the tip of the end effector caused by the drive of the transport drive unit.

[0088] The eleventh aspect is a substrate transport method according to the tenth aspect, wherein the storage unit stores vibration data indicating the vibration of the end effector caused by the transport drive unit before the substrate is loaded or unloaded, and the vibrator is vibrated at a frequency and amplitude based on the vibration data, and in the opposite phase to the phase of the vibration of the end effector detected by the vibration sensor.

[0089] A twelfth aspect is a substrate transport method according to the eleventh aspect, wherein a substrate sensor detects the area of ​​gap between substrates in the substrate container, a tolerance value for the amplitude of vibration of the tip of the end effector is set based on the area of ​​gap between substrates detected by the substrate sensor, and the transport drive unit controls the vibrator so that the vibration of the tip of the end effector detected by the vibration sensor falls below the tolerance value when the end effector moves toward the substrate container.

[0090] According to the first and tenth embodiments, the vibrator does not need to have a substrate transport function. Therefore, a drive unit suitable for reducing vibration at the tip of the end effector can be used as the vibrator. In other words, this embodiment contributes to reducing vibration of the end effector.

[0091] According to the second embodiment, since the vibrator is positioned closer to the tip of the end effector, vibrations at the tip of the end effector can be reduced with higher precision.

[0092] According to the third embodiment, since the positional resolution of the oscillator is small, vibration at the tip of the end effector can be reduced with higher precision.

[0093] According to the fourth embodiment, a small vibrator can be used, thereby suppressing the increase in vibration of the end effector caused by the weight of the vibrator.

[0094] According to the fifth embodiment, since the position resolution of the piezo actuator is very small, the oscillator can reduce the vibration of the end effector with greater precision.

[0095] According to the sixth embodiment, vibrations at the tip of the end effector can be detected more directly. Therefore, vibrations at the tip of the end effector can be detected with higher accuracy.

[0096] According to the seventh and eleventh embodiments, the control unit vibrates the vibrator based on vibration data stored in the memory unit. In other words, the control unit vibrates the vibrator in a predetermined vibration pattern. Therefore, the control unit can control the vibrator with simpler control.

[0097] According to the embodiments of Figure 8 and Figure 11, vibrations at the tip of the end effector can be reduced depending on the area of ​​the gap between the substrates.

[0098] According to the ninth and twelfth embodiments, vibrations at the tip of the end effector can be reduced more effectively. [Explanation of Symbols]

[0099] 20. Substrate transport device (first processing unit) 21 End Effectors 22 Conveyor drive unit 23 Reverse drive unit 25 Lifting drive unit 27 Vibration Sensor 28. Oscillator 90 Control Unit C board housing

Claims

1. A substrate transport device for loading and unloading substrates into and from a substrate container, An end effector that supports the circuit board, A transport drive unit including a lifting drive unit for raising and lowering the end effector, and a reciprocating drive unit for moving the end effector in the forward and backward direction relative to the substrate housing, A vibration sensor for detecting vibrations at the tip of the end effector, A vibrator, provided separately from the transport drive unit, vibrates the end effector vertically based on the detection of the vibration sensor, thereby reducing vibrations at the tip of the end effector caused by the drive of the transport drive unit. A substrate transport device equipped with the following features.

2. A substrate transport apparatus according to claim 1, The vibrator is provided between the base end of the end effector and the transport drive unit in a substrate transport device.

3. A substrate transport apparatus according to claim 1 or claim 2, A substrate transport device wherein the vertical position resolution of the vibrator is smaller than the position resolution of the lifting drive unit.

4. A substrate transport apparatus according to claim 1 or claim 2, A substrate transport device wherein the amplitude range of the vertical vibration of the vibrator is narrower than the range of movement of the end effector by the lifting drive unit.

5. A substrate transport apparatus according to claim 1 or claim 2, The vibrator is a substrate transport device that includes a piezo actuator.

6. A substrate transport apparatus according to claim 1 or claim 2, The vibration sensor includes an acceleration sensor provided at the tip of the end effector, in a substrate transport device.

7. A substrate transport apparatus according to claim 1 or claim 2, It comprises a storage unit and a control unit, The storage unit stores vibration data indicating the vibration of the end effector caused by the drive by the transport drive unit. A substrate transport device wherein the control unit vibrates the vibrator at a frequency and amplitude based on the vibration data, and in the opposite phase to the phase of the vibration of the end effector detected by the vibration sensor.

8. A substrate transport apparatus according to claim 7, The control unit determines the frequency components of the vibration of the end effector using a Fourier transform, and vibrates the vibrator based on these frequency components, in a substrate transport device.

9. A substrate transport apparatus according to claim 7, The substrate sensor further comprises a substrate sensor that detects the area of ​​the gap between the substrates within the substrate housing, A substrate transport device comprising: a control unit which sets an allowable amplitude for the vibration of the tip of the end effector based on the region of the gap between the substrates detected by the substrate sensor, and controls the vibrator such that the vibration of the tip of the end effector detected by the vibration sensor falls below the allowable amplitude.

10. A method for transporting substrates in and out of a substrate container, A substrate transport method comprising: a transport drive unit moving an end effector toward the substrate container; a vibration sensor detecting vibrations at the tip of the end effector; and a vibrator, provided separately from the transport drive unit, vibrating the end effector vertically based on the detection by the vibration sensor, thereby reducing vibrations at the tip of the end effector caused by the drive of the transport drive unit.

11. A substrate transport method according to claim 10, A substrate transport method comprising: a memory unit storing vibration data indicating the vibration of the end effector caused by the transport drive unit before the substrate is loaded or unloaded; and vibrating the vibrator at a frequency and amplitude based on the vibration data, and in the opposite phase to the phase of the vibration of the end effector detected by the vibration sensor.

12. A substrate transport method according to claim 11, The substrate sensor detects the area of ​​the gap between the substrates within the substrate housing, Based on the region of the gap between the substrates detected by the substrate sensor, the allowable amplitude of the vibration at the tip of the end effector is set. A substrate transport method comprising controlling the vibrator such that the vibration of the tip of the end effector detected by the vibration sensor falls below the allowable amplitude when the transport drive unit moves the end effector toward the substrate container.

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