PCB transport device

Abstract

To provide a substrate transport device that improves transport accuracy. [Solution] A substrate transport device comprising: a transport chamber provided with a tile-shaped unit having a coil and a Hall element; a transport unit having a permanent magnet and moving on the tile-shaped unit to transport a substrate; and a control unit that estimates the position of the transport unit based on the detected value of the Hall element, wherein the transport chamber has a first region for aligning the transport unit and a transport region which is a region other than the first region, the first region including the position of the transport unit when transferring and / or receiving the substrate to and from a mounting table, and an imaging device provided on the ceiling of the transport chamber for detecting the position of the transport unit in the first region by imaging the transport unit in the first region.

Description

Technical Field

[0001] The present invention relates to a substrate transfer device.

Background Art

[0002] Patent Document 1 discloses a substrate transfer device including a transfer unit that levitates on a planar motor provided in a transfer chamber and transfers a substrate.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] On one side, an object is to provide a substrate transfer device that improves transfer accuracy.

Means for Solving the Problems

[0005] To solve the above problems, according to one aspect, there is provided a substrate transfer device including: a tile-shaped unit provided in a transfer chamber and having a coil and a hall element; a transfer unit having a permanent magnet and moving on the tile-shaped unit to transfer a substrate; and a control unit that estimates the position of the transfer unit based on a detection value of the hall element. The transfer chamber has a first region for aligning the position of the transfer unit and a transfer region that is a region other than the first region. The first region includes the position of the transfer unit when delivering and / or receiving the substrate to / from a mounting table, and an imaging device is provided on the ceiling of the transfer chamber to detect the position of the transfer unit in the first region by imaging the transfer unit in the first region.

Effects of the Invention

[0006] From one perspective, it is possible to provide a substrate transport device that improves transport accuracy. [Brief explanation of the drawing]

[0007] [Figure 1] A plan view showing the configuration of an example of a substrate processing system according to one embodiment. [Figure 2] A perspective view showing an example of a transport unit according to one embodiment. [Figure 3] A perspective view illustrating the driving principle of a substrate transport device. [Figure 4] An example of a plan view showing the arrangement of temperature sensors. [Figure 5] An example of a plan view illustrating the arrangement of temperature sensors within a tile in an area requiring high precision. [Figure 6] An example of a functional block diagram of the control unit. [Figure 7] An example of a plan view illustrating the alignment of the transport unit when placing a circuit board on the mounting table. [Figure 8] Another example of a plan view illustrating the alignment of the transport unit when placing a circuit board on a mounting table. [Modes for carrying out the invention]

[0008] The following describes embodiments for implementing this disclosure with reference to the drawings. In each drawing, the same reference numerals are used for identical components, and redundant explanations may be omitted.

[0009] <Substrate processing system 100> An example of the overall configuration of a substrate processing system 100 according to one embodiment will be described with reference to Figure 1. Figure 1 is a plan view showing the configuration of an example of a substrate processing system 100 according to one embodiment.

[0010] The substrate processing system 100 shown in Figure 1 is a cluster structure (multi-chamber type) system. The substrate processing system 100 comprises a plurality of processing chambers 110, a vacuum transport chamber 120, a load lock chamber 130, an atmospheric transport chamber 140, a load port 150, and a control unit 160. In Figure 1, the longitudinal direction of the vacuum transport chamber 120 is defined as the X direction, the short direction (width direction) of the vacuum transport chamber 120 is defined as the Y direction, and the height direction of the vacuum transport chamber 120 is defined as the Z direction.

[0011] The processing chamber 110 is reduced to a predetermined vacuum atmosphere, and within it, a semiconductor wafer (hereinafter also referred to as "substrate W") is subjected to a desired process (etching, film deposition, cleaning, ashing, etc.). The processing chamber 110 is located adjacent to the vacuum transport chamber 120. The processing chamber 110 and the vacuum transport chamber 120 are connected by opening and closing a gate valve 112. The processing chamber 110 has a mounting table 111 on which the substrate W is placed. The operation of each part for processing in the processing chamber 110 is controlled by the control unit 160.

[0012] The vacuum transport chamber 120 is connected to a plurality of chambers (processing chamber 110, load lock chamber 130) via gate valves 112 and 132, and is depressurized to a predetermined vacuum atmosphere. Inside the vacuum transport chamber 120, a substrate transport device 125 for transporting substrates W is provided. The substrate transport device 125 has a planar motor 10 positioned in the vacuum transport chamber 120, and a plurality of transport units 30 (30A, 30B) that can move on the planar motor 10. Each transport unit 30 has a mover 31 that can move on the planar motor 10, and an arm 32 configured to hold the substrates W. The substrate transport device 125 loads and unloads substrates W between the processing chamber 110 and the vacuum transport chamber 120 in accordance with the opening and closing of gate valve 112. The substrate transport device 125 also loads and unloads substrates W between the load lock chamber 130 and the vacuum transport chamber 120 in accordance with the opening and closing of gate valve 132. The operation of the substrate transport device 125 and the opening and closing of the gate valves 112 and 132 are controlled by the control unit 160. The substrate transport device 125 (planar motor 10, transport unit 30) will be described later with reference to Figures 2 to 4.

[0013] Furthermore, the vacuum transport chamber 120 has a precision requirement area 200 (shown by a dashed line in Figure 1) where high alignment accuracy is required when the transport unit 30 moves. For example, the position of the transport unit 30 when it transfers the substrate W to the mounting table 111 in the processing chamber 110 and / or receives the substrate W from the mounting table 111 is within the precision requirement area 200 where high alignment accuracy is required. The position of the transport unit 30 when it transfers the substrate W to the mounting table 131 in the load lock chamber 130 and / or receives the substrate W from the mounting table 111 may also be within the precision requirement area 200.

[0014] On the other hand, within the vacuum transport chamber 120, the transport area 210 (an area within the vacuum transport chamber 120 other than the precision requirement area 200) that connects the precision requirement area 200 with other precision requirement areas 200 is an area where the alignment precision of the transport unit 30 is not required to be as high as that of the precision requirement area 200.

[0015] The load lock chamber 130 is located between the vacuum transport chamber 120 and the atmospheric transport chamber 140. The load lock chamber 130 has a mounting table 131 on which the substrate W is placed. The load lock chamber 130 is capable of switching between an atmospheric atmosphere and a vacuum atmosphere. The load lock chamber 130 and the vacuum transport chamber 120, which is in a vacuum atmosphere, are connected by opening and closing a gate valve 132. The load lock chamber 130 and the atmospheric transport chamber 140, which is in an atmospheric atmosphere, are connected by opening and closing a door valve 133. The switching between the vacuum atmosphere and the atmospheric atmosphere in the load lock chamber 130 is controlled by the control unit 160.

[0016] The atmospheric transfer chamber 140 has an atmospheric environment, and for example, a downflow of clean air is formed. Inside the atmospheric transfer chamber 140, a transfer device (not shown) for transferring the substrate W is provided. The transfer device (not shown) transfers the substrate W in and out between the load lock chamber 130 and the atmospheric transfer chamber 140 according to the opening and closing of the door valve 133. Note that the operation of the transfer device (not shown) and the opening and closing of the door valve 133 are controlled by the control unit 160.

[0017] Also, a load port 150 is provided on the wall surface of the atmospheric transfer chamber 140. The load port 150 is attached with a carrier (not shown) in which the substrate W is accommodated or an empty carrier. As the carrier, for example, a FOUP (Front Opening Unified Pod) or the like can be used.

[0018] The transfer device (not shown) can take out the substrate W accommodated in the carrier attached to the load port 150 and place it on the mounting table 131 of the load lock chamber 130. Also, the transfer device (not shown) can take out the substrate W placed on the mounting table 131 of the load lock chamber 130 and accommodate it in the carrier attached to the load port 150.

[0019] The control unit 160 includes a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), and an HDD (Hard Disk Drive). The control unit 160 may have other storage areas such as an SSD (Solid State Drive) instead of the HDD. In the storage areas such as the HDD and the RAM, a recipe in which the procedure of the process, the conditions of the process, and the transfer conditions are set is stored.

[0020] The CPU controls the processing of the substrate W in each processing chamber 110 according to a recipe, and controls the transport of the substrate W. The HDD or RAM may store programs for executing the processing of the substrate W and the transport of the substrate W in each processing chamber 110. The programs may be provided by being stored on a storage medium, or they may be provided by an external device via a network.

[0021] Next, an example of the operation of the substrate processing system 100 will be described. Here, as an example of the operation of the substrate processing system 100, the process of processing a substrate W housed in a carrier attached to the load port 150 in the processing chamber 110 and then housing it in an empty carrier attached to the load port 150 will be described. At the start of the operation, the gate valves 112, 132 and the door valve 133 are closed, and the load lock chamber 130 is in an atmospheric environment.

[0022] The control unit 160 opens the door valve 133. The control unit 160 controls the transport device in the atmospheric transport chamber 140 to remove the substrate W from the carrier in the load port 150 and place it on the mounting table 131 in the load lock chamber 130. Once the substrate W is placed on the mounting table 131 in the load lock chamber 130 and the transport device retracts from the load lock chamber 130, the control unit 160 closes the door valve 133.

[0023] The control unit 160 controls the exhaust device (not shown) of the load lock chamber 130 to exhaust the air inside the chamber, switching the load lock chamber 130 from an atmospheric environment to a vacuum environment.

[0024] Next, the substrate W placed on the mounting table 131 in the load lock chamber 130 is transported to the processing chamber 110 and placed on the mounting table 111. Specifically, the control unit 160 opens the gate valve 132. The control unit 160 controls the substrate transport device 125, which will be described later, to insert the arm 32 into the load lock chamber 130 to a preset transfer position, hold the substrate W placed on the mounting table 131 in the load lock chamber 130, and transport it to the vacuum transport chamber 120. When the arm 32 retracts from the load lock chamber 130, the control unit 160 closes the gate valve 132.

[0025] The control unit 160 opens the gate valve 112 of the processing chamber 110 to which the substrate is being transported. The control unit 160 controls the substrate transport device 125 to insert the arm 32 into the processing chamber 110 to a preset transfer position and place the substrate W being held onto the mounting table 111 of the processing chamber 110. When the arm 32 retracts from the processing chamber 110, the control unit 160 closes the gate valve 112.

[0026] The control unit 160 controls the processing chamber 110 to perform the desired processing on the substrate W.

[0027] When the processing of the substrate W is complete, the substrate W placed on the mounting table 111 in the processing chamber 110 is transported to the load lock chamber 130 and placed on the mounting table 131. Specifically, the control unit 160 opens the gate valve 112. The control unit 160 controls the substrate transport device 125 to insert the arm 32 into the processing chamber 110 to a preset transfer position, holds the substrate W placed on the mounting table 111 in the processing chamber 110, and transports it to the vacuum transport chamber 120. When the arm 32 retracts from the processing chamber 110, the control unit 160 closes the gate valve 112.

[0028] The control unit 160 opens the gate valve 132. The control unit 160 controls the substrate transport device 125 to insert the arm 32 into the load lock chamber 130 to a preset transfer position and place the held substrate W onto the mounting table 131 in the load lock chamber 130. When the arm 32 retracts from the load lock chamber 130, the control unit 160 closes the gate valve 132.

[0029] The control unit 160 controls the gas supply device (not shown) for the load lock chamber 130 to supply, for example, clean air into the chamber, and switches the load lock chamber 130 from a vacuum atmosphere to an atmospheric atmosphere.

[0030] The control unit 160 opens the door valve 133. The control unit 160 controls the transport device (not shown) to remove the substrate W placed on the mounting table 131 of the load lock chamber 130 and place it in the carrier of the load port 150. Once the substrate W has been removed from the mounting table 131 of the load lock chamber 130 and the transport device (not shown) has moved away from the load lock chamber 130, the control unit 160 closes the door valve 133.

[0031] In the substrate processing system 100, the substrate transport device 125 was described as transporting substrates W placed on the loading platform 131 of the load lock chamber 130 to the loading platform 111 of the processing chamber 110, and then transporting the processed substrates W from the loading platform 111 of the processing chamber 110 to the loading platform 131 of the load lock chamber 130, but the system is not limited to this configuration. The substrate transport device 125 may also be configured to transport substrates W placed on the loading platform 111 of one processing chamber 110 to the loading platform 111 of another processing chamber 110.

[0032] <Substrate transport device 125> Next, the substrate transport device 125 will be described further. The substrate transport device 125 includes a planar motor 10 located in the vacuum transport chamber 120 and a transport unit 30 that can move on the planar motor 10. As shown in Figure 4, which will be described later, the planar motor 10 is formed by arranging a plurality of tile-shaped units 11 (see Figure 3) within the vacuum transport chamber 120.

[0033] Figure 2 is a perspective view showing an example of a transport unit 30 according to one embodiment. The transport unit 30 includes a mover 31 and an arm 32. The mover 31 is configured to move by magnetic levitation on a planar motor 10. One end of the arm 32 is fixed to the mover 31, and the other end is configured to hold the substrate W. Multiple transport units 30 may be provided in the vacuum transport chamber 120.

[0034] The tile-shaped unit 11 of the planar motor 10 and the mover 31 of the transport unit 30 will be further explained with reference to Figure 3. Figure 3 is a perspective view illustrating the driving principle of the substrate transport device 125.

[0035] The tile-shaped unit 11 of the planar motor 10 has multiple coils 15 arranged within a housing 14 made of a non-magnetic metal or resin. The coils 15 generate a magnetic field when current is supplied to them. The control unit 160 (see Figure 1) is configured to individually control the current value supplied to each coil 15.

[0036] The mover 31 has multiple permanent magnets 35 arranged in a row. The magnetic field generated by the coil 15 allows the mover 31 to magnetically levitate on the tile-shaped unit 11. Furthermore, the magnetic field generated by the coil 15 allows the mover 31 to move on the tile-shaped unit 11 and on the planar motor 10 formed by multiple tile-shaped units 11.

[0037] With this configuration, the control unit 160 (see Figure 1) is configured to control the position (horizontal position (X-axis direction, Y-axis direction), height (Z-axis direction) position (levitation amount)) and orientation (tilt around the X-axis, tilt around the Y-axis, tilt around the Z-axis) of the transport unit 30 (mover 31) by controlling the current values ​​of each coil 15 of the planar motor 10 (tile-shaped unit 11).

[0038] Furthermore, the tile-shaped unit 11 is provided with multiple Hall elements (position detection sensors) 16 within the housing 14. The Hall elements 16 are an example of magnetic sensors and are sensors for detecting the position and orientation of the mover 31. Specifically, the Hall elements 16 detect a detected value (Hall voltage) corresponding to the magnetic flux density formed by the permanent magnet 35 of the mover 31. The detected value of the Hall elements 16 is input to the control unit 160 (see Figure 1). The control unit 160 calculates the magnetic flux density at the position (magnetic flux measurement position) of each Hall element 16 based on the detected values ​​of the multiple Hall elements 16, and estimates the position and orientation of the mover 31 based on the calculated magnetic flux densities at the multiple magnetic flux measurement positions.

[0039] Here, multiple coils 15 and Hall elements 16 are provided inside the housing 14 of the tile-shaped unit 11. When the transport unit 30 is levitated and moved on the planar motor 10, the coil 15 corresponding to the position of the transport unit 30 is energized. When the coil 15 is energized, it generates heat, and the heat from the coil 15 is transferred to the Hall elements 16. The heat from the coil 15 is also transferred to the Hall elements 16 in adjacent tile-shaped units 11. As a result, a temperature difference may occur in the Hall elements 16.

[0040] The Hall element 16 loses sensitivity as its temperature rises. Therefore, if a temperature difference occurs between multiple Hall elements 16, a difference in sensitivity will occur between them. This may cause the position and orientation of the mover 31 estimated based on the magnetic flux density detected by the Hall element 16 to deviate from the actual position and orientation of the mover 31. This may reduce the alignment accuracy of the transport unit 30.

[0041] In this embodiment, the planar motor 10 has a temperature sensor 17 provided inside the housing 14 of the tile-shaped unit 11. For example, a thermocouple can be used as the temperature sensor 17. The value detected by the temperature sensor 17 is input to the control unit 160 (see Figure 1).

[0042] Next, the arrangement of the temperature sensors 17 (17A, 17B) will be explained using Figures 4 and 5. Figure 4 is an example of a plan view showing the arrangement of the temperature sensors 17.

[0043] In this embodiment, the planar motor 10 is formed by arranging a plurality of tile-shaped units 11. A precision requirement area 200 is provided on the planar motor 10. A temperature sensor 17A is provided in the precision requirement area 200 of the planar motor 10.

[0044] Figure 5 is an example of a plan view illustrating the arrangement of temperature sensors 17A within a tile-shaped unit 11 in the accuracy requirement region 200.

[0045] As shown in Figure 5(a), the temperature sensor 17A may be provided individually for each Hall element 16. This allows for accurate detection of the temperature of each Hall element 16 in the accuracy requirement region 200.

[0046] Furthermore, as shown in Figure 5(b), the temperature sensor 17A may have multiple Hall elements 16 provided within the tile-shaped unit 11. For example, in a rectangular tile-shaped unit 11, temperature sensors 17A may be provided at the corners and the center. This allows for the estimation of the temperature distribution within the tile-shaped unit 11 in the accuracy requirement region 200 based on the temperature detected by the temperature sensors 17A, and the estimation of the temperature of each Hall element 16 in the accuracy requirement region 200. In addition, the cost of the tile-shaped unit 11 can be reduced by reducing the number of temperature sensors 17A.

[0047] Returning to Figure 4, the planar motor 10 is equipped with a temperature sensor 17B for measuring the temperature distribution of the entire planar motor 10. For example, in a planar motor 10 formed in a rectangular shape by arranging multiple tile-shaped units 11, multiple temperature sensors 17B may be provided along the outer edge, or a temperature sensor 17B may be provided on the central side of the planar motor 10. This makes it possible to estimate the temperature distribution within the planar motor 10 based on the temperature detected by the temperature sensor 17B, and to estimate the temperature of each Hall element 16 in the accuracy requirement region 200.

[0048] Next, the control unit 160, which estimates the position of the transport unit 30, will be explained using Figure 6. Figure 6 is an example of a functional block diagram of the control unit 160. The control unit 160 includes a temperature acquisition unit 161, a Hall element temperature estimation unit 162, a magnetic flux density calculation unit 163, and a position estimation unit 164. The memory unit of the control unit 160 stores the positions of the temperature sensors 17 (17A, 17B) (temperature measurement positions) and the positions of the Hall elements 16 (magnetic flux measurement positions).

[0049] The temperature acquisition unit 161 receives the detection value from the temperature sensor 17 and acquires the temperature at each temperature measurement location detected by the temperature sensor 17.

[0050] The Hall element temperature estimation unit 162 estimates the temperature of each Hall element 16 based on the temperature at each temperature measurement location acquired by the temperature acquisition unit 161. For example, when estimating the temperature of a Hall element 16 within the accuracy requirement area 200, the Hall element temperature estimation unit 162 estimates the temperature distribution of the tile-shaped units 11 within the accuracy requirement area 200 based on the temperature at each temperature measurement location detected by the temperature sensor 17A, and then estimates the temperature of each Hall element 16 based on the estimated temperature distribution of the tile-shaped units 11. Also, when estimating the temperature of a Hall element 16 within the transport area 210 (see Figure 1), the Hall element temperature estimation unit 162 estimates the temperature distribution of the planar motor 10 based on the temperature at each temperature measurement location detected by the temperature sensor 17B, and then estimates the temperature of each Hall element 16 based on the estimated temperature distribution of the planar motor 10.

[0051] The magnetic flux density calculation unit 163 receives the temperature of each Hall element 16 and the detected value (Hall voltage) of each Hall element 16, which are estimated by the Hall element temperature estimation unit 162, and calculates the magnetic flux density at each magnetic flux measurement position detected by the Hall element 16. Here, the magnetic flux density calculation unit 163 compensates the detected value of the Hall element 16 based on the temperature of the Hall element 16 estimated by the Hall element temperature estimation unit 162 and the temperature characteristics of the Hall element 16. As a result, the magnetic flux density calculation unit 163 calculates the magnetic flux density at each magnetic flux measurement position in which the temperature characteristics of the Hall element 16 have been compensated.

[0052] The position estimation unit 164 estimates the position and orientation of the transport unit 30 (permanent magnet 35) based on the magnetic flux density calculated by the magnetic flux density calculation unit 163.

[0053] Figure 7 is an example of a plan view illustrating the alignment of the transport unit 30 when placing the substrate W on the mounting table 111.

[0054] A temperature sensor 17A (see Figures 4 and 5) is provided in the accuracy requirement region 200. This allows for accurate detection of the transport unit 30's position in the accuracy requirement region 200 by correcting the temperature of the Hall element 16. This improves the positioning accuracy of the transport unit 30. Furthermore, it allows for accurate placement of the substrate W onto the mounting table 111.

[0055] Although a thermocouple installed within the tile-shaped unit 11 was used as an example of a temperature sensor 17 for detecting the temperature of the Hall element 16, it is not limited to this. As a temperature sensor 17 for detecting the temperature of the Hall element 16, for example, a thermal camera installed on the ceiling of the vacuum transport chamber 120 and imaging the tile-shaped unit 11 within the accuracy requirement area 200 may be used. The Hall element temperature estimation unit 162 estimates the temperature of each Hall element 16 based on the temperature distribution of the tile-shaped unit 11 imaged by the thermal camera.

[0056] Furthermore, the Hall element temperature estimation unit 162 may estimate the amount of heat generated by each coil 15 based on the amount of current supplied to each coil 15. Then, the Hall element temperature estimation unit 162 may estimate the temperature distribution of the tile-shaped unit 11 (planar motor 10) based on the estimated amount of heat generated by each coil 15 and the temperature at each temperature measurement position detected by the temperature sensor 17, and estimate the temperature of each Hall element 16 based on the estimated temperature distribution of the tile-shaped unit 11 (planar motor 10). This makes it possible to estimate the temperature distribution of the tile-shaped unit 11 (planar motor 10) while taking into account the amount of heat generated by the coils 15, so that the temperature of each Hall element 16 can be estimated with greater accuracy. Therefore, the position and orientation of the transport unit 30 can be estimated with even greater accuracy.

[0057] Next, other configurations for improving alignment accuracy in the accuracy requirement region 200 will be explained using Figure 8. Figure 8 is another example of a plan view illustrating the alignment of the transport unit 30 when placing the substrate W on the mounting table 111.

[0058] A position detection sensor 18 is provided to detect the position of the transport unit 30 within the accuracy requirement area 200. The position detection sensor 18 is, for example, a laser displacement sensor provided on the side wall of the vacuum transport chamber 120. The position detection sensor 18 has two position detection sensors 18A provided on the side wall where the gate valve 112 of the vacuum transport chamber 120 is located, and two position detection sensors 18B provided on the other side wall of the vacuum transport chamber 120, and detects the position and orientation of the transport unit 30 (mover 31). This improves the alignment accuracy of the transport unit 30. In addition, the substrate W can be accurately placed on the mounting table 111.

[0059] In addition, while a laser displacement sensor installed on the side wall of the vacuum transport chamber 120 was described as an example of a position detection sensor 18 for detecting the position of the transport unit 30 within the accuracy requirement area 200, it is not limited to this. As a position detection sensor 18 for detecting the position of the transport unit 30 within the accuracy requirement area 200, for example, an imaging device (e.g., a CCD camera) installed on the ceiling of the vacuum transport chamber 120 to image the transport unit 30 within the accuracy requirement area 200 may be used.

[0060] Although the substrate processing system 100 has been described above, this disclosure is not limited to the embodiments described above, and various modifications and improvements are possible within the scope of the gist of this disclosure as described in the claims. [Explanation of Symbols]

[0061] 10 Planar motors 11 tile-shaped units 15 coils 16 Hall elements 17 Temperature sensor 18 Position detection sensor 30, 30A~30C Conveyor Unit 31 Mover 32 Arms 35 Permanent Magnets 100 substrate processing systems 110 Processing Room 120 Vacuum Conveying Chamber (Conveying Chamber) 130 Load Lock Room 140 Atmospheric Convection Chamber 150 Load Ports 160 Control Unit 200 Accuracy required area 210 Transport Area

Claims

[Claim 1] A tile-shaped unit having a coil and a Hall element is provided in the transport chamber, A transport unit having a permanent magnet and moving on the tile-shaped unit to transport the substrate, The system includes a control unit that estimates the position of the transport unit based on the detected value of the Hall element, The transport chamber has a first area for aligning the transport unit and a transport area which is an area other than the first area. The first region includes the position of the transport unit when transferring and / or receiving the substrate to and from the mounting table, The transport chamber is provided with an imaging device that is mounted on the ceiling and detects the position of the transport unit within the first region by imaging the transport unit within the first region. PCB transport device.

Images