JP2011108958A - Semiconductor wafer carrying device and carrying method using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To shorten a stop time in self-diagnosis and automatic correction of a semiconductor wafer carrying device, to simplify maintenance, and to lower the cost of the semiconductor wafer carrying device. <P>SOLUTION: The semiconductor wafer carrying device includes a load port portion where a wafer storage container can be installed, a carrying robot portion which has a hand for gripping a wafer and carries the wafer, and an aligner which determines the direction of the wafer. At least one of the load port portion and aligner has a sensor provided to the load port portion or aligner, and the semiconductor wafer carrying device has a controller which measures the position of the hand with respect to at least one of the load port portion and aligner using the sensor, and corrects the position of the hand on the basis of the measured value thereof. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a semiconductor wafer transfer apparatus and a transfer method using the same.

  In a semiconductor wafer transfer device, there are means such as automatic correction of the transfer position of the robot and self-diagnosis for detecting a deviation from the transfer route in order to guarantee high-precision transfer of the wafer. Conventionally, the following three methods have been proposed for these means.

  (1) A sensor is provided at the tip of the hand, and an automatic teaching target is detected to correct the position.

  (2) The automatic teaching pseudo wafer provided with the sensor is transferred to the target to correct the position.

  (3) The hand position is detected by an apparatus equipped with an optical sensor, and an abnormality is determined from the positional deviation.

  Said (1)-(3) is described in patent documents 1-3, respectively.

  Patent Document 1 discloses a mini-enclosure that forms a wafer transfer chamber between a semiconductor manufacturing apparatus that processes a wafer and a wafer storage cassette that supplies the wafer to the semiconductor manufacturing apparatus and collects the processed wafer. A wafer transfer robot equipped with a wafer handling mechanism is placed in this mini-en housing, a detector provided in the hand of the wafer transfer robot, and a reference slit (automatic teaching target) installed in the mini-en housing And a wafer transfer device that controls the moving direction of the wafer transfer robot based on the position of the reference slit.

  In Patent Document 2, a substrate is transported above a mounting table via a transport arm, the substrate is placed on a plurality of support pins that can be moved up and down, and the transport arm is returned to the outside of the mounting table. In a substrate transfer device that lowers the pins and places the substrate on the mounting table, prepare a disk (automatic teaching pseudo disk) of the same size as the substrate as a jig, and allow the arm to move backward A technique for demanding is disclosed. In this technique, a camera is mounted on the disc so that the lower part can be visually recognized through a through hole formed in a central portion, and among the plurality of insertion holes formed in the disc so that the plurality of support pins are loosely inserted. At least one of these is provided with detection means that can detect the presence or absence of a support pin, the transport arm and support pin are moved relative to each other in a horizontal plane, and the center of the disc is matched with a known center target while monitoring with a camera. The transport arm and the support pin are moved relative to each other in the vertical direction, and the tip of the support pin is detected by the detection means. Then, a position where the transport arm is moved relative to the disk by at least the amount exceeding the thickness of the transport arm from the detection position of the tip of the support pin is obtained by calculation, and is set as a retreat permission position of the transport arm.

  In Patent Document 3, the position of the arm reference point set in the arm of the arm robot is measured in the member transfer system in which the processing member is carried into and out of the chamber by the arm robot, and the arm reference point is set in the chamber. A technique for controlling the arm robot based on the coordinate position of the arm reference point obtained at the time when it matches the chamber reference point is disclosed.

JP 2009-16604 A JP 2003-218186 A JP 11-254359 A

  In the above-described prior art, the self-diagnosis and automatic correction of the transfer device are performed using the automatic teaching device at the time of introduction of the device and at the time of maintenance for stopping the movement of the device. At that time, it was necessary to check the operation accuracy of the robot using a dedicated jig or a dedicated sensor.

  An object of the present invention is to shorten the downtime, simplify the maintenance, and reduce the cost of the semiconductor wafer transfer device in self-diagnosis and automatic correction of the semiconductor wafer transfer device.

  A semiconductor wafer transfer apparatus according to the present invention includes a load port unit on which a wafer storage container can be installed, a hand that holds a wafer, a transfer robot unit that transfers the wafer, and an aligner that determines the orientation of the wafer. A semiconductor wafer transfer apparatus comprising: at least one of the load port unit and the aligner having a sensor provided in the load port unit or the aligner, and using the sensor, at least the load port unit and the aligner. It has a controller which measures the position of the hand with respect to one, and corrects the position of the hand based on this measured value.

  According to the present invention, the load port unit and the sensor of the aligner can be used for detecting the position of the hand installed in the transfer robot unit of the semiconductor wafer transfer device, and a special device for self-diagnosis and automatic correction. It is not necessary to install a dedicated jig or the like, and the cost of the apparatus can be reduced.

  Further, according to the present invention, since the self-diagnosis and automatic correction are performed by the semiconductor wafer transfer device alone, the self-diagnosis and automatic correction can be performed during the standby time of the semiconductor wafer transfer device to shorten the maintenance time. .

It is a top view which shows the semiconductor wafer conveyance apparatus which concerns on this invention. It is a side view which shows the semiconductor wafer conveyance apparatus which concerns on this invention. It is a schematic side view which shows the conveyance robot part which concerns on this invention. It is a schematic perspective view which shows the aligner which concerns on this invention. It is a schematic perspective view which shows the load port part which concerns on this invention. It is a schematic rear view which shows the load port part which concerns on this invention. It is a perspective view which shows the position detection operation | movement of the hand by the aligner which concerns on this invention. It is a side view which shows the aligner and light-shielding detection sensor which concern on this invention. It is a side view which shows the position detection operation | movement of the hand by the aligner and shading detection sensor which concern on this invention. It is sectional drawing which shows the position detection operation | movement of the hand by the load port part which concerns on this invention. It is a top view which shows the hand of the Example by this invention. It is a side view which shows the hand of the Example by this invention. It is a block diagram which shows the sensor, control part, etc. of the miniene sample conveyance system of the Example by this invention. It is a flowchart which shows the procedure in the case of performing the self-diagnosis and automatic correction | amendment of a hand in the aligner of the Example by this invention. It is a flowchart which shows the procedure in the case of performing the self-diagnosis and automatic correction | amendment of a hand in the load port part of the Example by this invention.

  Hereinafter, a semiconductor wafer transfer apparatus and a transfer method using the same according to embodiments of the present invention will be described.

  This embodiment is basically configured as follows.

  The semiconductor wafer transfer device includes a load port unit on which a wafer storage container can be installed, a hand that holds the wafer, a transfer robot unit that transfers the wafer, and an aligner that determines the orientation of the wafer, At least one of the load port unit and the aligner includes a sensor provided in the load port unit or the aligner. And it has a controller which measures the position of the hand with respect to at least one of the load port part and the aligner using the sensor, and corrects the position of the hand based on this measured value. In addition, the controller calculates a drive control amount from a predetermined position of the transfer robot unit to the load port unit or the aligner based on the measurement position of the hand, and based on the calculated value, the load A relative position of the hand with respect to the port unit or the aligner is calculated, and the position of the hand is corrected based on the calculated value.

  In the semiconductor wafer transfer apparatus, the sensor is a wafer detection sensor for detecting the presence or absence of the wafer in the aligner, and the transfer robot unit detects a motor for driving the hand and a rotational position of the motor. The controller measures the position of the hand using the wafer detection sensor, and measures the position of the hand relative to the aligner from the drive amount of the motor detected using the encoder. The position of the hand is corrected.

  In the semiconductor wafer transfer apparatus, the sensors are a horizontal light-shielding detection sensor and a vertical light-shielding detection sensor of the load port unit, and the transport robot unit detects a motor that drives the hand and a rotational position of the motor. The controller measures the position of the hand using the horizontal direction light-shielding detection sensor and the vertical direction light-shielding detection sensor, and calculates the load from the driving amount of the motor detected using the encoder. The position of the hand with respect to the port portion is measured, and the position of the hand is corrected.

  In the semiconductor wafer transfer apparatus, the vertical light shielding detection sensor is a wafer jump sensor, and the controller measures the position of the hand using the wafer pop sensor and detects the position of the motor detected using the encoder. The position of the hand with respect to the load port unit is measured from the driving amount, and the position of the hand is corrected.

  The semiconductor wafer conveyance device performs the correction during a standby time during which the wafer is not conveyed.

  In the semiconductor wafer transfer device, the controller is configured to measure the aligner or the position of the hand relative to the aligner or the load port unit measured using the sensor and the drive amount of the motor detected using the encoder. When the difference between the position of the hand with respect to the load port unit exceeds an abnormal value, it is determined as abnormal.

  In the semiconductor wafer transfer apparatus, the hand has a through hole for allowing light emitted from the light projector to the light receiver of the sensor in the aligner or load port section to pass therethrough.

  In the transfer method using the semiconductor wafer transfer device, the semiconductor wafer transfer device is used to perform the correction, determine a transfer route, and transfer the wafer.

  Embodiments of the present invention will be described below with reference to the drawings.

  In the semiconductor wafer transfer apparatus for supplying and discharging the wafer to the semiconductor manufacturing apparatus, the main transfer is that the wafer is taken out from the FOUP (Front Opening Unified Pod), supplied to the semiconductor manufacturing apparatus, and discharged from the semiconductor manufacturing apparatus. The wafer is taken out and stored in the FOUP. Such a semiconductor wafer transfer device is referred to as a mini-ene sample transfer system. The FOUP may be called a wafer storage container.

  FIG. 1 is a plan view showing a miniene sample transport system according to the present invention.

  FIG. 2 is a side view showing a miniene sample transport system according to the present invention.

  A mini-ene sample transport system (hereinafter referred to as EFEM (Equipment Front End Module)) includes a mini-en housing 101, an FFU unit 102 (Fan Filter Unit), load port units 103, 104, and 105, a transport robot unit 107, and an aligner 108. And a controller 112. A semiconductor manufacturing apparatus 106 (also referred to as a semiconductor inspection apparatus) is a higher-level apparatus of EFEM.

  The mini-en housing 101 includes an FFU unit 102, a transfer robot unit 107, an aligner 108, and a controller 112. The mini-en housing 101 covers the outside of the system with a fixing plate (exterior cover) and provides a space isolated from the outside. The mini-en housing 101 also has a function of a connection unit that supplies a wafer from the load port units 103, 104, and 105 to the semiconductor manufacturing apparatus 106.

  The FFU unit 102 includes a blower fan and a filter, is installed on the top of the mini-en housing 101, and realizes a clean environment in the mini-en housing 101 by down-flowing clean air.

  The load port units 103, 104, and 105 include a FOUP fixing base and a FOUP lid opening / closing mechanism. The load port portions 103, 104, and 105 are connected to the mini-en housing 101 and serve as sample transport ports for the semiconductor manufacturing apparatus 106 and the mini-en housing 101.

  The transfer robot unit 107 includes a hand 109 for gripping a wafer, and can perform a movement in the horizontal direction (horizontal movement), a movement in the vertical direction (vertical movement), and a turning operation. The transfer robot unit 107 transfers the wafer between the load port units 103, 104, and 105 and the semiconductor manufacturing apparatus 106.

  The controller 112 communicates with the semiconductor manufacturing apparatus 106 (high-order apparatus), controls each mechanism, and controls the mini-en conveying system.

  Hereinafter, an outline of a wafer transfer sequence using EFEM which is an embodiment of the present invention will be shown.

  In FIG. 1, the transfer robot unit 107 takes out the wafer 111 from the FOUP 110 installed in the load port units 103, 104, and 105 via the arm 302 and the hand 109, and moves horizontally (X direction movement) as necessary. The ascending operation is performed and conveyed to the aligner 108. After the orientation of the wafer 111 is determined by the aligner 108, the wafer 111 is transferred again to the connection portion (not shown) of the semiconductor manufacturing apparatus 106 by handling of the transfer robot 107. In addition, the transfer robot unit 107 collects the wafer 111 that has been subjected to the predetermined processing by the semiconductor manufacturing apparatus 106 from the connection unit, and transfers the wafer 111 to the FOUP 110 installed in the load port units 103, 104, and 105 for storage.

  FIG. 3 is a schematic side view showing the transfer robot unit according to the present invention.

  The transfer robot unit 107 includes a main body 301, an upper arm 302 of the robot main body 301, and a hand 109 installed at the tip of the arm 302. The transfer robot unit 107 holds the wafer with the hand 203 and transfers the wafer by the lifting / lowering operation, the horizontal movement and the turning operation of the robot body 301, and the horizontal expansion / contraction of the arm 202. All of these operations are performed by transmitting the rotation of the motor. The rotational position of the motor can be detected using an encoder.

  FIG. 4 is a schematic perspective view showing an aligner according to the present invention.

  The aligner 108 includes an aligner main body 401, a wafer gripping unit 402 using, for example, an electrostatic chuck or a vacuum chuck, a light shielding detection sensor 403, and a light shielding amount detection sensor 404. After the transfer robot unit 107 places the wafer 111 on the wafer gripping unit 402, the aligner 108 checks the presence or absence of the wafer 111 with the light shielding detection sensor 403, and after confirming that the wafer 111 is present, grips the wafer 111. The wafer gripper 402 is rotated. The edge of the rotating wafer 111 is monitored by the light shielding amount detection sensor 404, the notch of the edge of the wafer 111 is detected, and the wafer 111 is rotated and stopped so that the direction of the notch becomes a predetermined direction. The light shielding detection sensor 403 may be called a wafer detection sensor.

  FIG. 5 is a schematic perspective view showing a load port portion according to the present invention, and FIG. 6 is a schematic rear view showing the load port portion according to the present invention.

  The load port unit 500 corresponds to the load port units 103, 104, and 105 in FIG. 1, and includes a load port main body 501, a FOUP mounting unit 502, a FOUP lid opening / closing unit 503, a horizontal light shielding detection sensor 601, and the like. , And a vertical direction light shielding detection sensor 602. The load port unit 500 opens the lid of the supplied FOUP 110 so that the transfer robot unit 107 can access the wafer 111 inside the FOUP 110. Further, the horizontal light shielding detection sensor 601 detects the number of wafers 111 and the storage position of the wafer 111 inside the FOUP 110, and transmits the information to the semiconductor wafer transfer device. If the wafer 111 has jumped out of the FOUP 110, it is detected by the vertical light shielding detection sensor 602, and information that the wafer 111 is abnormal is transmitted to the semiconductor wafer transfer device. The vertical light shielding detection sensor 602 may be called a wafer pop-out sensor.

  Optical axes 603 and 604 are formed by light emitted from the projectors of the horizontal direction light shielding detection sensor 601 and the vertical direction light shielding detection sensor 602 toward the light receiver.

  The horizontal light shielding detection sensor 601 may be configured to be able to move in the vertical direction and detect the number and storage position of the wafers 111 stored in the FOUP 110. In this case, the horizontal light shielding detection sensor 601 may be called a wafer mapping sensor. The wafer mapping sensor detects (measures) the quantity and the storage position of the wafer 111 by detecting a state where the wafer 111 blocks the optical axis 603 in the process of moving up and down. The position of the hand may be measured using this wafer mapping sensor.

  Also in this case, the position of the hand can be corrected by the controller using the measured position of the hand and the driving amount of the transfer robot unit.

  Prior to the operation of the EFEM, the transfer robot unit 107 is taught, and the relative positions of the transfer robot unit 107, the aligner, and the load port unit 500 are obtained.

  The method will be described below.

  FIGS. 7A, 7B, and 7C show an embodiment in which the position of the hand is detected using the aligner sensor.

  First, the hand 109 approaches the aligner 108 until the hand 109 interferes with the optical axis 701 of the light shielding detection sensor 403 and the light shielding is detected, and is stopped when the light is shielded. In the stopped state, the horizontal relative position between the transfer robot unit 107 and the aligner 108 is calculated from the horizontal drive control amount of the transfer robot unit 107 until the hand 109 shields light. Here, the optical axis 701 is formed by light emitted from the light projector of the light blocking detection sensor 403 toward the light receiver.

  FIG. 8 shows a configuration for detecting the hand position using the sensor of the load port unit.

  The hand 109 is entered until the vertical light shielding detection sensor 602 detects light shielding, and is stopped when the light is shielded. In the stopped state, the horizontal relative position between the hand 109 (conveying robot unit) and the FOUP lid opening / closing unit 503 (load port unit) is calculated from the horizontal drive control amount of the conveying robot unit until the hand 109 is shielded from light. Can do.

  Further, the hand 109 of the horizontal light shielding detection sensor 601 and the transport robot unit is moved to the measurement position, the main body is raised or lowered until the hand 109 is shielded from light, and is stopped when the light is shielded. In the stopped state, the vertical relative position between the transfer robot unit and the load port unit can be calculated from the ascending drive control amount of the transfer robot unit until the hand 109 shields light.

  With the above method, the relative positions of the transfer robot unit, the aligner, and the load port unit are obtained, and the drive amount (control amount) of the transfer robot unit in the wafer transfer sequence can be obtained using the data of the relative positions.

  Hereinafter, the self-diagnosis of the transfer robot unit after the EFEM is operated will be described.

  The self-diagnosis of the transfer robot unit uses the sensors of the aligner and load port unit during the standby time of the semiconductor wafer transfer device and the time previously set as self-diagnosis, using the same method as the calculation of the relative position described above. , Detect the position of the hand. In this case, the drive amount of the transfer robot unit when the relative position between the transfer robot unit and the load port unit and aligner in the self-diagnosis performed last time is calculated, and the drive amount of the transfer robot unit in the current self-diagnosis Compare.

  When a difference occurs in the drive amount, the drive control amount of the transfer robot unit in the transfer sequence is corrected based on the difference, and an error that occurs in the transfer accuracy can be prevented. Further, by setting a threshold value in advance for the difference in drive amount and transmitting information indicating that the abnormality is present to the arithmetic unit when a change equal to or greater than the threshold value occurs, it is possible to detect an abnormality in the transport robot unit.

  FIG. 9A is a top view showing a hand of an embodiment according to the present invention, and FIG. 9B is a side view showing a hand of an embodiment according to the present invention.

  In part of the hand 109, through holes 901, 902, and 903 are provided for passing through the light shielding detection sensor 403 shown in FIG. 7B and the optical axes of the horizontal light shielding detection sensor 601 and the vertical light shielding detection sensor 602 shown in FIG. The hand 109 may be stopped at the center position of the through holes 901, 902, and 903, and the position of the hand 109 may be detected.

  Thereby, the accuracy of position detection can be improved.

  FIG. 10 is a configuration diagram showing sensors, a control unit, and the like of the miniene sample transport system according to the embodiment of the present invention.

  In this figure, a robot 1002 includes a motor 1003 and an encoder 1004, and the operation of the hand 109 is controlled by a motor control unit 1001. The motor 1003 is a drive source for the robot 1002, and the encoder 1004 detects the rotational position of the motor 1003.

  The aligner 1005 is provided with a light shielding detection sensor 403 and a light shielding amount detection sensor 404. The load port unit 1006 is provided with a horizontal light shielding detection sensor 601 and a vertical light shielding detection sensor 602.

  The motor control unit 1001, aligner 1005, and load port unit 1006 are connected to the controller 112 via signal lines 1007, 1008, 1009. The controller 112 performs self-diagnosis and automatic correction of the hand 109 based on information from the encoder 1004, the light shielding detection sensor 403, the light shielding amount detection sensor 404, the horizontal light shielding detection sensor 601, and the vertical light shielding detection sensor 602.

  FIG. 11 is a flowchart showing a procedure for performing hand self-diagnosis and automatic correction in the aligner according to the embodiment of the present invention.

  In this figure, first, the hand is moved to the aligner (S1101), and the hand is moved to the detection position (S1102). And it is discriminate | determined based on the information from an encoder, a light-shielding detection sensor, and a light-shielding amount detection sensor whether there exists any deviation (difference) in the position of a hand (S1103).

  When there is a deviation (when the deviation is equal to or greater than the threshold), the amount of deviation is transmitted from the controller to the motor control unit (S1104), and the deviation is corrected (corrected) (S1105). Here, the amount of deviation is defined as a correction value.

  When there is no deviation (when the deviation is less than the threshold value), the hand self-diagnosis and automatic correction are terminated.

  FIG. 12 is a flowchart showing a procedure when hand self-diagnosis and automatic correction are performed in the load port unit according to the embodiment of the present invention.

  In this figure, first, the hand is moved to the load port section (S1201), and the hand is moved to the detection position (S1202). Then, it is determined whether the position of the hand is misaligned based on information from the encoder, the horizontal light shielding detection sensor, and the vertical light shielding detection sensor (S1203).

  When there is a deviation (when the deviation is equal to or greater than the threshold value), the amount of deviation is transmitted from the controller to the motor control unit (S1204), and the deviation is corrected (corrected) (S1205).

  When there is no deviation (when the deviation is less than the threshold value), the hand self-diagnosis and automatic correction are terminated.

  11 and 12, when the amount of deviation (correction value) is large and exceeds an abnormal value (referred to as an abnormal value), the controller determines that it is abnormal and stops the semiconductor wafer transfer device, and the operator A signal (sound (buzzer, etc.), light (lamp lighting, flashing, etc.) etc. is emitted to perform maintenance by.

  101: Mini-en housing, 102: FFU unit, 103, 104, 105: Load port unit, 106: Semiconductor manufacturing apparatus, 107: Transfer robot unit, 108: Aligner, 109: Hand, 110: FOUP, 111: Wafer, 112 : Controller, 301: Robot body, 302: Arm, 303: Hand, 401: Aligner body, 402: Wafer gripping part, 403: Light shielding detection sensor, 404: Light shielding amount detection sensor, 501: Load port body, 502: FOUP installed Part, 503: FOUP lid opening / closing part, 601: horizontal shading detection sensor, 602: vertical shading detection sensor, 701: optical axis, 901, 902, 903: through-hole.

Claims (10)

  A semiconductor wafer transfer apparatus including a load port part capable of installing a wafer storage container, a hand holding a wafer, a transfer robot part for transferring the wafer, and an aligner for determining the direction of the wafer, At least one of the load port unit and the aligner has a sensor provided in the load port unit or the aligner, and measures the position of the hand with respect to at least one of the load port unit and the aligner using the sensor. And a controller for correcting the position of the hand based on the measured value.   The controller calculates a drive control amount from a predetermined position of the transfer robot unit to the load port unit or the aligner based on the measurement position of the hand, and based on the calculated value, the load port unit 2. The semiconductor wafer transfer apparatus according to claim 1, wherein a relative position of the hand with respect to the aligner is calculated, and the position of the hand is corrected based on the calculated value.   The sensor is a wafer detection sensor for detecting the presence or absence of the wafer in the aligner, and the transfer robot unit includes a motor for driving the hand and an encoder for detecting a rotational position of the motor, The controller measures the position of the hand using the wafer detection sensor, measures the position of the hand relative to the aligner from the driving amount of the motor detected using the encoder, and corrects the position of the hand The semiconductor wafer transfer apparatus according to claim 1, wherein:   The sensors are a horizontal direction shading detection sensor and a vertical direction shading detection sensor of the load port unit, and the transfer robot unit includes a motor that drives the hand and an encoder that detects a rotational position of the motor, The controller measures the position of the hand using the horizontal light-shielding detection sensor and the vertical light-shielding detection sensor, and determines the position of the hand relative to the load port unit from the driving amount of the motor detected using the encoder. The semiconductor wafer transfer apparatus according to claim 1, wherein the position of the hand is corrected.   The horizontal light-shielding detection sensor is a wafer mapping sensor for measuring the quantity and storage position of the wafer stored in the wafer storage container so as to be movable in the vertical direction, and using the wafer mapping sensor 5. The semiconductor wafer transfer apparatus according to claim 4, wherein the position of the hand is measured, and the controller corrects the position of the hand using the position of the hand and the driving amount of the transfer robot unit.   The vertical light shielding detection sensor is a wafer pop-out sensor, and the controller measures the position of the hand using the wafer pop-out sensor and calculates the load port from the driving amount of the motor detected using the encoder. 5. The semiconductor wafer transfer apparatus according to claim 4, wherein the position of the hand with respect to a part is measured and the position of the hand is corrected.   The semiconductor wafer transfer apparatus according to claim 1, wherein the correction is performed during a standby time during which the transfer of the wafer is not performed.   The controller is configured to measure the position of the hand relative to the aligner or the load port unit measured using the sensor and the hand relative to the aligner or the load port unit measured from the driving amount of the motor detected using the encoder. The semiconductor wafer transfer device according to claim 1, wherein when the difference from the position exceeds an abnormal value, it is determined as abnormal.   The said hand has a through-hole for allowing the light emitted toward the light receiver from the light projector of the sensor of an aligner or a load port part to pass through. Semiconductor wafer transfer device.   A transfer method comprising: performing the correction using the semiconductor wafer transfer apparatus according to claim 1, determining a transfer route, and transferring the wafer.

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