Device for transporting a substrate, and method for transporting a substrate

Abstract

To provide a technique for more accurately moving a substrate conveyance module along a preset pathway.SOLUTION: In a device for conveying a substrate, a tile for movement provided in a conveyance region of the substrate comprises: a plurality of first magnets capable of changing states of magnetic fields; and a movement surface. A substrate conveyance module holding the substrate comprises a second magnet which receives actuation of a magnetic force acting between the second magnet and the magnetic fields of the first magnets, and is configured to be movable along the movement surface while being floated from the movement surface. A detection unit detects an index value corresponding to a magnitude of deviation from a preset pathway regarding an actual movement pathway of the substrate conveyance module. A correction parameter calculation unit calculates a correction parameter so as to reduce the magnitude of the deviation. A conveyance control unit performs correction for changing the states of the magnetic fields for moving the substrate conveyance module based on the correction parameter in the subsequent conveyance of the substrate along the preset pathway.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present disclosure relates to an apparatus for transporting a substrate and a method for transporting a substrate.

Background Art

[0002] For example, in an apparatus for performing processing on a semiconductor wafer (hereinafter also referred to as a "wafer") as a substrate, the wafer is transported between a carrier containing the wafer and a wafer processing chamber where the processing is executed. Various configurations of wafer transport mechanisms are used for wafer transport.

[0003] For example, Patent Document 1 describes a substrate transport system that forms a coplanar plane with a first planar motor and a second planar motor provided on a vertically movable first lift, and floats and moves a substrate carrier between these planar motors. According to the description of Patent Document 1, this substrate transport system is configured to smoothly transfer the substrate carrier between the two planar motors by adjusting the arrangement of a plurality of coils provided in the first and second planar motors.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] The present disclosure provides a technique for more accurately moving a substrate transport module along a preset set path.

Means for Solving the Problems

[0006] The present disclosure is an apparatus for transporting a substrate to a substrate processing chamber in which processing of the substrate is performed, A plurality of first magnets provided in a conveyance area of the substrate from a handover position of the substrate to the outside to a processing position of the substrate in the substrate processing chamber and configured to be able to change a magnetic field state, and a moving tile including a moving surface. A substrate conveyance module that holds the substrate and includes a second magnet that receives an action of a magnetic force that is at least one of a repulsive force and an attractive force acting between the magnetic field of the first magnet, and is configured to be movable along the moving surface in a state of floating from the moving surface using the magnetic force. A conveyance control unit that controls a magnetic field formed by the plurality of first magnets so that the substrate conveyance module moves along a preset set path. A detection unit that detects an index value corresponding to a magnitude of a deviation from the set path for an actual movement path of the substrate conveyance module that moves along the moving surface by the control of the magnetic field by the conveyance control unit. A correction parameter calculation unit that calculates a correction parameter for correcting a magnetic force acting on the second magnet based on the index value so that the magnitude of the deviation is reduced, and is provided. The conveyance control unit performs correction to change a state of the magnetic field based on the correction parameter in conveyance of a substrate along the subsequent set path. i The detection unit is composed of a sensor that detects the acceleration of the substrate transfer module, and the index value is the magnitude of the acceleration at which the substrate transfer module moves in a direction intersecting with the direction along the set path. Relates to an apparatus.

Effect of the Invention

[0007] According to the present disclosure, the substrate conveyance module can be moved more accurately along a preset set path.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Embodiments for Carrying Out the Invention

[0009] Hereinafter, the overall configuration of a wafer processing system 100 including an "apparatus for transferring a substrate" according to an embodiment of the present disclosure will be described with reference to FIG. 1. FIG. 1 shows a multi-chamber type wafer processing system 100 including a plurality of wafer processing chambers 110. The wafer processing chamber 110 corresponds to a substrate processing chamber for processing the wafer W. As shown in FIG. 1, the wafer processing system 100 includes a load port 141, an atmospheric transfer chamber 140, a load lock chamber 130, a vacuum transfer chamber 120, and a plurality of wafer processing chambers 110. In the following description, the direction in which the load port 141 is provided is defined as the front side of the wafer processing system 100.

[0010] In the wafer processing system 100, the load port 141, the atmospheric transfer chamber 140, the load lock chamber 130, and the vacuum transfer chamber 120 are arranged in this order in the horizontal direction from the front side. Also, the plurality of wafer processing chambers 110 are provided side by side on the left and right of the vacuum transfer chamber 120 when viewed from the front side. The load port 141 is configured as a mounting table on which a carrier C for accommodating the wafer W to be processed is placed, and four are arranged side by side in the left-right direction when viewed from the front side. As the carrier C, for example, a FOUP (Front Opening Unified Pod) or the like can be used.

[0011] The inside of the atmospheric transfer chamber 140 is at atmospheric pressure (normal pressure), and for example, a downflow of clean air is formed. Also, inside the atmospheric transfer chamber 140, a wafer transfer mechanism 142 for transferring the wafer W is provided. The wafer transfer mechanism 142 transfers the wafer W between the carrier C and the load lock chamber 130. Further, an alignment chamber 150 for aligning the wafer W is provided, for example, on the left side surface of the atmospheric transfer chamber 140.

[0012] A plurality of load lock chambers 130 are installed side by side on the left and right between the vacuum transfer chamber 120 and the atmospheric transfer chamber 140. The load lock chamber 130 has a lifting pin 131 that pushes up and holds the loaded wafer W from below. The lifting pins 131 in this example are provided in three at equal intervals in the circumferential direction and are configured to be movable up and down. The load lock chamber 130 is configured to be able to switch between an atmospheric pressure atmosphere and a vacuum atmosphere. The load lock chamber 130 and the atmospheric transfer chamber 140 are connected via a gate valve 133. Also, the load lock chamber 130 and the vacuum transfer chamber 120 are connected via a gate valve 132.

[0013] The vacuum transfer chamber 120 is depressurized to a vacuum atmosphere by a vacuum exhaust mechanism (not shown). In the example shown in FIG. 1, the vacuum transfer chamber 120 in which the wafer W is transferred under a vacuum atmosphere is configured by a rectangular housing that is long in the front-rear direction and rectangular in plan view. In the wafer processing system 100 of this example, a total of four wafer processing chambers 110, two on each of the left and right side wall portions of the vacuum transfer chamber 120, are provided. When the inside of the vacuum transfer chamber 120 shown in FIG. 1 is viewed from the front side and partitioned into two regions, a front stage and a rear stage, the wafer processing chambers 110 are installed so as to face each other across each region from the left and right. An opening for loading and unloading the wafer W is formed in the side wall portion of the vacuum transfer chamber 120 to which each wafer processing chamber 110 is connected, and a gate valve 121 configured to be freely opened and closed is provided at the opening.

[0014] Each wafer processing chamber 110 is connected to the vacuum transfer chamber 120 via a gate valve 121. Each wafer processing chamber 110 is evacuated to a vacuum atmosphere by a vacuum evacuation mechanism (not shown), and a wafer W is placed on a mounting table 111 provided therein, and a predetermined process is performed on the wafer W. The mounting area of the wafer W on the mounting table 111 corresponds to the processing position of the wafer W. The wafer processing chamber 110 has lifting pins 112 that push up and hold the loaded wafer W from below. In this example, three lifting pins 112 are provided at equal intervals in the circumferential direction and are configured to be movable up and down.

[0015] Examples of the processes performed on the wafer W include etching processes, film formation processes, cleaning processes, ashing processes, and the like. The mounting table 111 is provided with a heater (not shown) for heating the wafer W to a preset temperature, for example. When the process performed on the wafer W uses a process gas, the wafer processing chamber 110 is provided with a process gas supply unit (not shown) constituted by a shower head or the like. Further, the wafer processing chamber 110 may be provided with a plasma forming mechanism for plasmaizing the process gas.

[0016] A plurality of transfer modules 20 configured in a rectangular plate shape are accommodated in the vacuum transfer chamber 120. Each transfer module 20 is configured to be movable in the vacuum transfer chamber 120 by magnetic levitation. The transfer module 20 corresponds to the substrate transfer module of the present embodiment. In the wafer processing system 100 of this example, the wafer W is transferred between the load lock chamber 130 and each wafer processing chamber 110 using the transfer module 20.

[0017] The wafer processing system 100 includes a control unit 5. The control unit 5 is composed of a computer including a CPU and a storage unit, and controls each part of the wafer processing system 100. In the storage unit, a program in which a group of steps (instructions) for controlling the operation of the transfer module 20, the wafer processing chamber 110, etc. is assembled is recorded. This program is stored in a storage medium such as a hard disk, a compact disk, a magneto-optical disk, a memory card, etc., and is installed in the computer from there.

[0018] Hereinafter, with reference to FIGS. 2 and 3, the configuration of the equipment related to the transfer of the wafer W using the transfer module 20 will be described. The transfer module 20 includes a stage 2 which is a substrate holding part on which a wafer W having a diameter of 300 mm is placed and held. For example, the stage 2 is formed in a flat square plate shape with a side length of more than 300 mm.

[0019] The transfer module 20 enters the wafer processing chamber 110 and the load lock chamber 130, and performs the transfer of the wafer W with the lifting pins 112 and 131. In the transfer module 20, a slit 21 is formed for performing the transfer of the wafer W while avoiding interference with the lifting pins 112 and 131. The lifting pins 112 and 131 hold the wafer W in a state of protruding from the floor surface of the wafer processing chamber 110 and the load lock chamber 130. The slit 21 is formed along the trajectory through which the lifting pins 112 and 131 pass when the stage 2 enters and exits below the wafer W held by the lifting pins 112 and 131. The slit 21 is also formed so that the entering direction of the stage 2 to the lower position of the wafer W can be reversed by 180°. With the above-described configuration, the transfer module 20 and the lifting pins 112 and 131 do not interfere with each other, and they can be arranged vertically so that the centers of the transfer module 20 and the wafer W are aligned.

[0020] As schematically shown in FIG. 3, a plurality of tiles (moving tiles) 10 are provided on the floor surface sides of the load lock chamber 130, the vacuum transfer chamber 120, and the wafer processing chamber 110. These tiles 10 are provided in the transfer region of the wafer W from the transfer position of the wafer W between the external atmospheric transfer chamber 140 (the position where the lifting pins 131 are arranged) to the processing position of the wafer W in the wafer processing chamber 110. Inside each of the tiles 10, a plurality of moving surface side coils 11 are arranged. The moving surface side coils 11 generate a magnetic field when power is supplied from a power supply unit 53 described later. The moving surface side coils 11 correspond to the first magnets of the present embodiment.

[0021] On the other hand, inside the transfer module 20, a plurality of module side magnets 23 made of, for example, permanent magnets are arranged. A repulsive force (magnetic force) acts between the module side magnets 23 and the magnetic field generated by the moving surface side coils 11. By this action, the transfer module 20 can be magnetically levitated (magnetically floated) with respect to the moving surface on the upper surface side of the tile 10. Further, the tile 10 can adjust the position where the magnetic field is generated and the strength of the magnetic force by the plurality of moving surface side coils 11, and change the state of the magnetic field. By controlling this magnetic field, the transfer module 20 can be moved in a desired direction on the moving surface, the floating distance from the moving surface can be adjusted, and the orientation of the transfer module 20 can be adjusted.

[0022] The module side magnets 23 provided in the transfer module 20 correspond to the second magnets of the present embodiment. Note that the plurality of module side magnets 23 may be configured by coils that are supplied with power from a battery provided in the transfer module 20 and function as electromagnets, or may be configured by providing both permanent magnets and coils. In the wafer processing system 100 of this example, the tile 10 and the transfer module 20 schematically shown in FIG. 3 constitute a device (wafer transfer device 101) for transferring the wafer W.

[0023] FIG. 4 is a block diagram showing the electrical configuration of the wafer transfer device 101. DC power is supplied from the power supply unit 53 to each moving surface side coil 11 provided on the tile 10. The power supply unit 53 is connected to the aforementioned control unit 5 that controls the entire wafer processing system 100 via the bus 51. The control unit 5 has a function as a transfer control unit 501 that controls the operation of the transfer module 20 by controlling the magnetic field formed by the moving surface side coil 11 provided on the tile 10.

[0024] The control of the magnetic field of the moving surface side coil 11 is carried out using, as operating variables, the selection of the moving surface side coil 11 to which power is to be supplied, the amount of power supplied to the selected moving surface side coil 11, the switching of the power supply direction (the switching of the magnetic poles), etc. By adjusting these operating variables, the transfer module 20 can be moved along a preset set path.

[0025] The control unit 5 has a function as a transfer control unit 501 that controls the magnetic field formed by the moving surface side coil 11 so as to move the transfer module 20 along a preset set path in the wafer transfer device 101.

[0026] For example, when the carrier C is placed on the load port 141, a process recipe that defines the content of the process set for each of the plurality of wafers W accommodated therein is read out. Based on this process recipe, the transfer control unit 501 identifies the wafer processing chamber 110 capable of executing the process defined in the process recipe, and creates a transfer schedule for these plurality of wafers W. The transfer schedule includes, for example, information identifying the load lock chamber 130 used when loading and unloading the wafer W taken out from the carrier C into the vacuum transfer chamber 120, and the wafer processing chamber 110 that processes the wafer W. Further, the transfer schedule includes information identifying the transfer module 20 used when transferring the wafer W in the vacuum transfer chamber 120, and information identifying the path (set path) through which the wafer W passes when being transferred between the load lock chamber 130 and the wafer processing chamber 110.

[0027] The transfer control unit 501 controls the supply of power to each moving surface side coil 11 provided on the tile 10 based on the above-described transfer schedule. As a result, the magnetic field formed by the moving surface side coil 11 is adjusted. Then, by changing the magnetic force applied to the module side magnet 23 of the transfer module 20, the transfer module 20 can be moved along a preset set path.

[0028] In the wafer transfer apparatus 101 having the above-described configuration, if the transfer control unit 501 performs power supply control to each moving surface side coil 11 and can apply a magnetic force as designed to the transfer module 20, the transfer module 20 can be accurately moved along the set path. On the other hand, the arrangement positions of the moving surface side coils 11 in the tile 10, the module side magnets 23 in the transfer module 20, and the detectors (for example, Hall sensors) for detecting the position of the transfer module 20 may be displaced from the designed positions within the tolerance range. This also applies to the arrangement positions of the tiles 10 arranged in large numbers on the floor surface sides of the load lock chamber 130, the vacuum transfer chamber 120, and the wafer processing chamber 110. Also, characteristics such as the winding uniformity of each moving surface side coil 11 and the magnetic force of the module side magnet 23 vary for each individual device.

[0029] The inventor of the present application has found that when attempting to move the transfer module 20 along the set path 40 indicated by the broken line in FIGS. 5 and 6 due to the above-described various error factors, etc., the transfer module 20 may actually move in a vibrating manner along a movement path 41 deviated from the set path 40. When attempting to increase the moving speed of the transfer module 20, it is preferable to reduce such vibrations as much as possible in order to avoid contact between the moving transfer module 20 and other transfer modules 20 or devices.

[0030] Therefore, the wafer transfer apparatus 101 of the present disclosure includes a mechanism for detecting the magnitude of the deviation from the set path 40 for the actual movement path 41 of the transfer module 20 that moves along the moving surface of the tile 10 and correcting this deviation.

[0031] Regarding a mechanism for performing deviation correction, the transfer module 20 includes a known acceleration sensor 22 for detecting an index value corresponding to the magnitude of the force acting on the transfer module 20. The acceleration sensor 22 has a function of detecting the direction and magnitude of the acceleration of the moving transfer module 20. The acceleration sensor 22 corresponds to the detection unit in this example.

[0032] The acceleration sensor 22 in this example can detect the acceleration in each direction of the secondary coordinate system (the X'-Y'-Z' orthogonal coordinate system shown together in FIGS. 2, 3, 5, and 6) set for each transfer module 20. Note that the detection unit provided in the transfer module 20 may be constituted by a torque sensor that detects the angular acceleration applied to the transfer module 20. In this case, by decomposing the torque applied to the transfer module 20 in the direction along the secondary coordinate system, the magnitude of the acceleration acting in each direction can be specified.

[0033] The acceleration detected by the acceleration sensor 22 or the torque sensor increases or decreases corresponding to the force acting on the moving transfer module 20. Further, as will be described later with reference to FIG. 7, the acceleration of the transfer module 20 facing a predetermined direction is an index value corresponding to the magnitude of the deviation from the set path 40 with respect to the actual movement path 41 of the transfer module 20.

[0034] The information indicating the magnitude of the acceleration in each direction detected by the acceleration sensor 22 is output to the communication unit 52, for example, by wireless communication (FIG. 4). Furthermore, as shown in FIG. 4, the control unit 5 is provided with the function of a correction parameter calculation unit 502. The correction parameter calculation unit 502 has a function of obtaining a correction parameter for correcting the magnetic force acting on the module-side magnet 23 of the transfer module 20 so that the above-described deviation magnitude is reduced in the transfer of the wafer W along the set path 40. Based on this correction parameter, the control content of the magnetic field by the transfer control unit 501 is corrected. The specific method of correction will be described in the description of the operation of the wafer processing system 100 (wafer transfer device 101) described later.

[0035] For the wafer processing system 100 having the configuration described above, an example of the operation of transporting the wafer W using the transfer module 20 and processing the wafer W in the wafer processing chamber 110 will be described. First, when the carrier C containing the wafer W to be processed is placed on the load port 141, the processing recipe set for the wafer W in the carrier C is read out, and the transfer schedule for each wafer W is created. The transfer operation of the wafer W described below is performed based on this transfer schedule.

[0036] The wafer W accommodated in the carrier C is taken out by the wafer transfer mechanism 142 in the atmospheric transfer chamber 140. Next, the wafer W is transferred to the alignment chamber 150 for alignment. Further, when the wafer W is taken out from the alignment chamber 150 by the wafer transfer mechanism 142, the gate valve 133 of the load lock chamber 130 selected in the transfer schedule is opened.

[0037] Next, the wafer transfer mechanism 142 enters the load lock chamber 130 where the gate valve 133 is opened, and receives the wafer W by pushing it up with the lift pin 131 provided in the load lock chamber 130. Thereafter, when the wafer transfer mechanism 142 retreats from the load lock chamber 130, the gate valve 133 is closed. Further, the inside of the load lock chamber 130 is switched from the atmospheric pressure atmosphere to the vacuum atmosphere.

[0038] When the inside of the load lock chamber 130 becomes a vacuum atmosphere, the gate valve 132 on the vacuum transfer chamber 120 side is opened. Thereafter, the selected transfer module 20 in the transfer schedule is levitated magnetically and made to enter from the vacuum transfer chamber 120 into the load lock chamber 130. Next, the transfer module 20 is positioned below the wafer W supported by the lift pin 131, and the lift pin 131 is lowered to transfer the wafer W to the transfer module 20. Thereafter, the transfer module 20 holding the wafer W exits from the load lock chamber 130.

[0039] The transfer module 20 that has returned to the vacuum transfer chamber 120 moves within the vacuum transfer chamber 120 in a magnetically levitated state. Then, it moves toward the wafer processing chamber 110 selected in the transfer schedule among the four wafer processing chambers 110. At this time, the transfer module 20 moves along a preset path based on the transfer schedule.

[0040] When the transfer module 20 reaches a position facing the selected wafer processing chamber 110, the gate valve 121 of the wafer processing chamber 110 is opened. The transfer module 20 enters the wafer processing chamber 110 in a magnetically levitated state and moves to the area where the lifting pins 112 are arranged. Then, by raising the lifting pins 112, the wafer W held by the transfer module 20 is pushed up from below and received.

[0041] The transfer module 20 that has transferred the wafer W retreats from the wafer processing chamber 110 and then closes the gate valve 121. On the other hand, inside the wafer processing chamber 110, the lifting pins 112 are lowered to the lower side to transfer the wafer W to the mounting table 111. The wafer W placed on the mounting table 111 is heated by a heater, a processing gas is supplied through the processing gas supply unit, and if necessary, the processing gas is plasmaized to execute a predetermined process.

[0042] After executing the process of the wafer W for a preset period in this way, the heating of the wafer W is stopped and the supply of the processing gas is stopped. Also, if necessary, a cooling gas may be supplied into the wafer processing chamber 110 to cool the wafer W. Then, in a procedure reverse to that at the time of loading, the transfer module 20 is made to enter the wafer processing chamber 110, and the wafer W is returned from the wafer processing chamber 110 to the load lock chamber 130 through the vacuum transfer chamber 120. Furthermore, after switching the atmosphere of the load lock chamber 130 to the atmospheric pressure atmosphere, the wafer transfer mechanism 142 on the atmospheric transfer chamber 140 side takes out the wafer W in the load lock chamber 130 and returns it to a predetermined carrier C.

[0043] In the processing of the wafer W described above, regarding the actual movement path 41 of the transfer module 20, an example of a method for detecting the magnitude of the deviation from the set path 40 and correcting the deviation will be described with reference to FIGS. 5 to 8. FIG. 5 is a plan view showing an enlarged view of the vacuum transfer chamber 120 provided in the wafer processing system 100 shown in FIG. 1. In this vacuum transfer chamber 120, it is assumed that a set path 40 indicated by a broken line is set for the transfer module 20 arranged with the opening of the slit 21 facing the load lock chamber 130 side.

[0044] The set path 40 illustrated in FIG. 5 goes straight backward from the position P1 facing the load lock chamber 130 arranged in the center, and at the position P2 where the wafer processing chamber 110 (gate valve 121) on the subsequent stage side is arranged, the traveling direction is set to change to the left. Then, when it has moved to the position P3 facing the wafer processing chamber 110 on the left hand side of the subsequent stage side, the transfer module 20 is rotated 90° clockwise around the central axis indicated by the dashed-dotted line in FIG. 6 and stopped with the opening of the slit 21 facing the wafer processing chamber 110 side.

[0045] Regarding the above-described set path 40, actually, it is assumed that it passes through the movement path 41 indicated by the solid arrow in FIG. 5 and moves while vibrating left and right with respect to the traveling direction. For the sake of simplicity of explanation, in the transfer module 20, the vertical vibration indicated by the solid arrow in FIG. 6 and the rotational movement of the main body of the transfer module 20 around each of the X'-Y'-Z' axes are not considered.

[0046] The horizontal axis in FIGS. 7(a) to (e) indicates each position on the set path 40 leading to the positions P1 to P2 to P3 in FIG. 5. The vertical axis in FIG. 7(a) indicates the deviation width Δg in the direction orthogonal to the traveling direction of the actual movement path 41 with respect to the set path 40. Also, the vertical axis in FIG. 7(b) indicates the speed v in the X' axis direction of the sub-coordinates set for the transfer module 20 X’ and the vertical axis in FIG. 7(c) indicates the acceleration a X’ in the X' axis direction. Further, the vertical axis in FIG. 7(d) indicates the speed v Y’is shown, and the vertical axis in Fig. 7(e) is the acceleration a in the Y’-axis direction Y’ is shown. In addition, in these figures, the rotational operation of the transfer module 20 at the position P3 is not shown.

[0047] According to Fig. 7(b), in the movement from the position P1 to P2, in the direction along the traveling direction (X’-axis direction), the transfer module 20 accelerates at a substantially constant acceleration, then moves at a constant speed, and decelerates at an acceleration of approximately the same magnitude as that during acceleration when decelerating. As a result, as shown in Fig. 7(c), in the acceleration sensor 22 provided in the transfer module 20, the accelerations acting on the transfer module 20 during acceleration and deceleration in the traveling direction are detected.

[0048] On the other hand, the deviation of the actual movement path 41 from the set path 40 appears as a change in the speed of the transfer module 20 in the direction intersecting the traveling direction (Y’-axis direction), as shown in Fig. 7(d). Further, this change in speed is detected by the acceleration sensor 22 as a change in acceleration in the direction intersecting the traveling direction (Fig. 7(e)).

[0049] Furthermore, also in the movement from the position P2 to P3, in the direction along the traveling direction (Y’-axis direction), the accelerations acting on the transfer module 20 during acceleration and deceleration in the traveling direction are detected by the acceleration sensor 22 (Fig. 7(e)). Also, the influence of the deviation of the actual movement path 41 is detected by the acceleration sensor 22 as a change in acceleration in the direction intersecting the traveling direction (X’-axis direction) (Fig. 7(c)).

[0050] Thus, in straight-line movement, the deviation of the actual movement path 41 from the set path 40 can be detected by the acceleration sensor 22 as a change in acceleration in the direction intersecting the traveling direction. This acceleration is an index value indicating the magnitude of an external force, which is a force acting in a direction intersecting the direction along the set path 40. This external force includes those generated based on various error factors of the devices constituting the tile 10 and the transfer module 20 as described above.

[0051] Therefore, the correction parameter calculation unit 502 of this example obtains an external force F (= ma) based on the weight m of the transfer module 20 while holding the wafer W and the acceleration a in the direction intersecting the traveling direction. Further, the correction parameter calculation unit 502 calculates a correction force having a magnitude corresponding to the external force as a correction parameter and outputs it to the transfer control unit 501. The transfer control unit 501 corrects the state of the magnetic field formed by the moving surface side coil 11 so that the magnetic force acting on the module side magnet 23 of the transfer module 20 becomes larger by the amount of the correction force in the direction canceling the aforementioned deviation as compared with the time when the aforementioned acceleration a was acquired.

[0052] Specifically, compared with the magnetic field formed when the transfer module 20 is moved along the set path 40 on the premise that there is no influence of the external force, at each position of the movement path 41, a magnetic field is formed in which the magnetic force acting on the module side magnet 23 becomes larger by the amount of the correction force in the direction canceling the deviation. The magnetic field is adjusted by adjusting the various operation variables described above (selection of the moving surface side coil 11 to which power is supplied, power supply amount, switching of the power supply direction, etc.).

[0053] FIG. 8 shows an example of a method for calculating correction parameters. The horizontal axis in FIG. 8 indicates each position of the set path 40 of the transfer module 20. Further, the vertical axis in FIG. 8(a) indicates the acceleration a acting in the direction intersecting the traveling direction of the set path 40, and FIG. 8(b) indicates the correction force F'. In the example of FIG. 8(a), the positions Q1 to Q4 where the direction of the acceleration a (the direction of the external force) changes are specified, and the average accelerations a av (1) to a av (3) during the period of passing through these positions are obtained. Then, from these average accelerations a av and the weight m of the transfer module 20, a correction force F' (= ma av ) acting in the direction canceling the deviation is calculated. Also, the average value of the acceleration a may be obtained at shorter position intervals or time intervals than the example shown in FIG. 8 to improve the resolution of the correction force F'.

[0054] The calculation of the correction parameter (correction force) described above and the correction for changing the state of the magnetic field formed by the moving surface side coil 11 are applicable not only to the displacements in the X' and Y' axis directions of the sub-coordinates described with reference to FIGS. 5 and 7. For example, with respect to the displacement of the moving path 41 directed in the Z' axis direction shown in FIG. 6, the correction parameter can be calculated based on the change in acceleration directed in the Z' axis direction intersecting the traveling direction of the transport module 20.

[0055] Also, it is possible to calculate the correction parameter for the change in the moving speed along the traveling direction of the transport module 20, such as a longitudinal wave. For example, the difference value Δa between the change in acceleration when accelerating and decelerating as set along the set path 40 and the change in acceleration detected on the actual moving path 41 is obtained. Then, the correction force F' (= mΔa) is calculated from this difference value and the weight m of the transport module 20.

[0056] Furthermore, the above-described method can be applied not only to the case of linearly moving the transport module 20 but also to the correction of the displacement when the transport module 20 is moving in a curved motion. In this case, at each position of the set path 40 of the curve, the change in acceleration acting in the normal direction orthogonal to the tangent direction of the curve is detected. However, in the case of curved motion, even in the transport module 20 moving along the set path 40, the acceleration acting in the normal direction is detected. Therefore, at each position of the set path 40, the difference value Δa between the acceleration detected by the acceleration sensor 22 and the acceleration assumed to be detected when the transport module 20 moves along the set path 40 is obtained. Then, the correction force F' (= mΔa) is calculated from this difference value and the weight m of the transport module 20.

[0057] Furthermore, regarding the rotational operation of the transfer module 20 around each sub-coordinate shown in FIG. 6, it is also possible to detect the magnitude of the deviation from the set path 40 and correct the deviation for the actual movement path 41 of the transfer module 20 related to the rotational operation. As an example of the set path 40, a 90° rotation orbit R around the position P3 in FIG. 5 can be cited. In this case, for example, a plurality of acceleration sensors 22 are provided at different positions of the tile 10, and from the magnitude and direction of the acceleration detected by each acceleration sensor 22, the position of the rotation axis of the transfer module 20 and the angular velocity around the rotation axis can be obtained.

[0058] Then, the plurality of acceleration sensors 22 detect, as an index value, the angular acceleration in the direction intersecting the set path 40 (in the case of the rotation orbit R, the angular acceleration related to the rotational movement around the X' axis or Y' axis orthogonal to the Z' axis). Then, the correction parameter calculation unit 502 can calculate the magnitude N (= Iα) of the correction moment force N for correcting the deviation based on the angular acceleration α in the intersecting direction and the moment of inertia I determined from the shape of the transfer module 20, the density distribution of the constituent members, and the position of the rotation axis. The transfer control unit 501 performs correction to change the state of the magnetic field formed by the moving surface side coil 11 so that the magnetic force acting on the module side magnet 23 becomes larger by the amount of the correction moment force in the direction canceling out the aforementioned deviation as compared with the time when the aforementioned angular acceleration α is acquired.

[0059] Next, an example of the timing for performing the above correction will be described. First, an example can be cited where a trial period is provided in which only the movement operation of the transfer module 20 along the set path 40 is executed before starting the processing of the wafer W in the wafer processing chamber 110. During the trial period, in the set path 40, the transfer module 20 may be moved while actually transferring the wafer W.

[0060] In this case, regarding the movement operation of the transfer module 20 during the trial operation period, the acceleration sensor 22 detects index values (acceleration and angular acceleration). The correction parameter calculation unit 502 calculates correction parameters by the method described above based on the index values detected during the trial operation period. Then, based on the calculated correction parameters, the transfer control unit 501 performs correction to change the magnetic field state so that the correction of the deviation described above is performed during the processing period, which is the period when the trial operation period ends and the wafer W is processed in the wafer processing chamber 110.

[0061] Second, an example can be given of the case where, during the processing period, which is the period when the wafer W is processed in the wafer processing chamber 110, the acceleration sensor 22 detects index values during a movement operation of moving the transfer module 20 along the set path 40. The correction parameter calculation unit 502 calculates correction parameters by the method described above based on the index values detected during the movement operation. At this time, the index values may be detected during a plurality of movement operations, and the average value thereof may be adopted as the index value of the movement operation. Based on the calculated correction parameters, the correction parameter calculation unit 502 performs correction to change the magnetic field state so that the correction of the deviation described above is performed during another movement operation of moving the transfer module 20 along the same set path 40 after the movement operation described above.

[0062] According to the wafer transfer device 101 according to the present embodiment, the transfer module 20 can be moved more accurately along the preset set path. As a result, when the transfer module 20 is moved at high speed, contact with other transfer modules 20 and devices can be avoided.

[0063] Here, it is not limited to the case where the magnitude of the acceleration in the direction in which the transfer module 20 moves in a direction intersecting the direction along the set path 40 is detected as the index value corresponding to the magnitude of the force acting on the transfer module 20. For example, the deviation width between the actual movement path 41 from the set path 40 may be detected and used as an index value. In this case, as the sensor constituting the detection unit, a camera that images the position of the transfer module 20 within the movement plane, or a Hall sensor that detects the position of the transfer module 20 from the tile 10 side may be employed. Also, the detection unit may be constituted by a laser displacement meter that detects the position of the transfer module 20 based on the distance from the irradiation position of the laser light. By detecting the position of the transfer module 20, the actual movement path 41 can be specified, and the deviation width from the set path 40 can be obtained.

[0064] At this time, the transfer control unit 501 obtains the acceleration, which is the second-order time derivative value of the time change of the detected deviation width. Further, based on this acceleration, the transfer control unit 501 calculates a correction force having a magnitude corresponding to the external force acting on the transfer module 20 in the intersecting direction and uses it as a correction parameter. Then, the correction parameter calculation unit 502 performs the above-described correction so that the magnetic force acting on the module-side magnet 23 becomes larger by the amount of the correction force in the direction canceling the deviation as compared with the time when the deviation width is acquired.

[0065] Here, the transfer module 20 can also be configured to be capable of moving in a floating state by changing the distance from the movement plane of the tile 10. In this case, the detection of the various above-described index values may be performed a plurality of times by changing the distance from the movement plane of the transfer module 20. The correction parameter calculation unit 502 can estimate the index value at the distance from the preset movement plane by interpolation or extrapolation based on the change in the index value detected under conditions with different distances from the movement plane. The correction parameter calculation unit 502 can calculate the correction parameter corresponding to the distance from the preset movement plane based on this estimation result.

[0066] In addition to transporting the wafer W as described above, the transfer module 20 can also be configured to transport objects to be transferred with different weights from the wafer W, such as replacement parts in the wafer processing chamber 110. In this case, the detection of the various index values described above may be performed multiple times by changing the load applied to the transfer module 20. Based on the changes in the index values detected under these conditions with different loads, the correction parameter calculation unit 502 can estimate the index values of the weight of the object to be transferred by the transfer module 20 by interpolation or extrapolation. Based on this estimation result, the correction parameter calculation unit 502 can calculate a correction parameter corresponding to the weight of the object to be transferred by the transfer module 20.

[0067] In the embodiment described with reference to FIGS. 1 to 6, an example of the configuration in which the tiles 10 are arranged on the floor surface sides of the load lock chamber 130, the vacuum transfer chamber 120, and the wafer processing chamber 110, and the transfer module 20 is magnetically levitated on a horizontal moving surface has been described. However, the moving surface is not limited to being horizontal, and may be an inclined surface or a vertical surface. Also in this case, the acceleration sensor 22 of the transfer module 20 is subjected to the action of at least one of the repulsive force and the attractive force, which is a magnetic force, between the magnetic field of the moving surface side coil 11 on the tile 10 side, and can move in a state of floating from the moving surface. For the transfer module 20 moving on these inclined surfaces and vertical surfaces as well, it is possible to perform correction to change the state of the magnetic field formed by the moving surface side coil 11 based on the detection of index values such as the acceleration of the transfer module 20 by the detection unit and the deviation width from the set path 40, the calculation of the correction parameter by the correction parameter calculation unit 502, and the correction parameter by the transfer control unit 501.

[0068] Furthermore, the configuration of the transfer module 20 to which the technology of the present disclosure can be applied is not limited to those described in FIGS. 2 and 3. For example, instead of the square plate-shaped appearance, a transfer module 20 having a disk-shaped appearance may be used. Alternatively, a fork may be provided so as to extend laterally from the main body of the rectangular plate-shaped or disc-shaped transfer module 20 provided with the module-side magnet 23, and the wafer W may be held on this fork. In this case, even if the tile 10 is not provided in the wafer processing chamber 110 or the load lock chamber 130, it is possible to enter the fork and transfer the wafer W.

[0069] The embodiments disclosed this time should be considered as illustrative in all respects and not restrictive. The above embodiments may be omitted, replaced, or changed in various forms without departing from the scope and gist of the appended claims.

Explanation of Reference Numerals

[0070] W Wafer 10 Tile 11 Moving Surface Side Coil 101 Wafer Transfer Device 100 Wafer Processing System 110 Wafer Processing Chamber 120 Vacuum Transfer Chamber 20 Transfer Module 22 Acceleration Sensor 23 Module-Side Magnet 501 Transfer Control Unit 502 Correction Parameter Calculation Unit

Claims

1. An apparatus for transporting a substrate to a substrate processing chamber where substrate processing is performed, comprising: a plurality of first magnets provided in a substrate transport region from a substrate delivery position between the apparatus and the outside to a substrate processing position in the substrate processing chamber, the plurality of first magnets being configured to be able to change a magnetic field state; and a moving tile having a moving surface; a substrate transport module that holds the substrate and includes a second magnet that is subjected to an action of a magnetic force that is at least one of a repulsive force and an attractive force acting between the second magnet and the magnetic field of the first magnet, and is configured to be movable along the moving surface in a state of floating from the moving surface by using the magnetic force; a transport control unit that controls the magnetic field formed by the plurality of first magnets so that the substrate transport module moves along a preset set path; a detection unit that detects an index value corresponding to a magnitude of a deviation from the set path for an actual movement path of the substrate transport module that moves along the moving surface by control of the magnetic field by the transport control unit; a correction parameter calculation unit that calculates a correction parameter for correcting the magnetic force acting on the second magnet based on the index value so that the magnitude of the deviation is reduced; and the transport control unit performs correction to change the state of the magnetic field based on the correction parameter in subsequent substrate transport along the set path; the detection unit is configured by a sensor that detects an acceleration of the substrate transport module, and the index value is a magnitude of an acceleration with which the substrate transport module moves in a direction intersecting a direction along the set path. The apparatus.

2. The correction parameter calculation unit calculates, as the correction parameter, a correction force having a magnitude corresponding to an external force acting on the substrate transport module in the intersecting direction based on the acceleration, and the transport control unit compares with when the index value is acquired, and performs the correction so that the magnetic force acting on the second magnet becomes larger by the correction force in a direction canceling the deviation. The apparatus according to claim 1.

3. The detection of the index value by the detection unit is performed during a trial period, which is a period during which the substrate transport module is moved along the set path before starting substrate processing in the substrate processing chamber. The apparatus according to claim 1 or 2, wherein the conveyance control unit performs correction to change the state of the magnetic field during a processing period, which is a period for processing a substrate in the substrate processing chamber after the trial period, based on the correction parameter.

4. The detection of the index value by the detection unit is performed by a first moving operation of moving the substrate transfer module along the set path during a processing period, which is a period for processing a substrate in the substrate processing chamber. The apparatus according to claim 1 or 2, wherein the conveyance control unit performs correction to change the state of the magnetic field in another moving operation of moving the substrate transfer module along the set path after the first moving operation, based on the correction parameter.

5. The substrate transfer module is configured to be able to change the distance from the moving surface when moving in a floating state. The detection of the index value is performed a plurality of times by changing the distance from the moving surface of the substrate transfer module. The apparatus according to any one of claims 1 to 4, wherein the correction parameter calculation unit calculates the correction parameter corresponding to the preset distance from the moving surface based on the index values detected under conditions where the distances from the moving surface are different.

6. The substrate transfer module is configured to be able to transfer a transfer object having a weight different from that of the substrate. The detection of the index value is performed a plurality of times by changing the load applied to the substrate transfer module. The apparatus according to any one of claims 1 to 5, wherein the correction parameter calculation unit calculates the correction parameter corresponding to the weight of the transfer object conveyed by the substrate transfer module based on the index values detected under conditions where the loads are different.

7. A method for transferring a substrate to a substrate processing chamber in which substrate processing is performed. A plurality of first magnets provided in a conveyance region of the substrate from a handover position of the substrate to the outside to a processing position of the substrate in the substrate processing chamber, and configured to be able to change a magnetic field state, and a moving tile including a moving surface, and a substrate holding member including a second magnet that holds the substrate and is subjected to an action of a magnetic force that is at least one of a repulsive force and an attractive force acting between the second magnet and the magnetic field of the first magnet, and using a substrate conveyance module configured to be movable along the moving surface in a floating state from the moving surface by using the magnetic force, a step of controlling a magnetic field formed by the plurality of first magnets to move the substrate conveyance module along a preset set path; a step of detecting an index value corresponding to a magnitude of a deviation from the set path for an actual movement path of the substrate conveyance module moving along the moving surface by the control of the magnetic field; a step of calculating a correction parameter for correcting a magnetic force acting on the second magnet based on the index value so that the magnitude of the deviation is reduced; a step of performing a correction of changing a state of the magnetic field based on the correction parameter in conveyance of the substrate along the set path after the step of moving the substrate conveyance module, including: In the step of detecting the index value, a method of using a sensor that detects an acceleration of the substrate conveyance module and detecting, as the index value, a magnitude of an acceleration in a direction intersecting a direction along the set path in which the substrate conveyance module moves.

8. In the step of calculating the correction parameter, as the correction parameter, a correction force having a magnitude corresponding to an external force acting on the substrate conveyance module in the intersecting direction is calculated based on the acceleration, and in the step of performing the correction, the correction is performed such that the magnetic force acting on the second magnet becomes larger by the correction force in a direction canceling the deviation as compared with when the index value is acquired. The method according to claim 7.

9. The step of detecting the index value is performed during a trial period which is a period of moving the substrate conveyance module along the set path before starting processing of the substrate in the substrate processing chamber, The step of performing the correction is performed so as to change a state of the magnetic field during a processing period which is a period of processing the substrate in the substrate processing chamber after the trial period. The method according to claim 7 or 8.

10. The step of detecting the index value is performed by a first moving operation of moving the substrate transfer module along the set path during a processing period which is a period of processing the substrate in the substrate processing chamber. The step of performing the correction is performed so as to change the state of the magnetic field in another moving operation of moving the substrate transfer module along the set path after the first moving operation. The method according to claim 7 or 8.

11. The substrate transfer module is configured to be able to change the distance from the moving surface when moving in a floating state. The step of detecting the index value is performed a plurality of times by changing the distance from the moving surface of the substrate transfer module. The step of calculating the correction parameter calculates the correction parameter corresponding to the preset distance from the moving surface based on the index values detected under conditions where the distances from the moving surfaces are different. The method according to any one of claims 7 to 10.

12. The substrate transfer module is configured to be able to transfer a transfer object having a weight different from that of the substrate. The step of detecting the index value is performed a plurality of times by changing the load applied to the substrate transfer module. The step of calculating the correction parameter calculates the correction parameter corresponding to the weight of the transfer object transferred by the substrate transfer module based on the index values detected under conditions where these loads are different. The method according to any one of claims 7 to 11.

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