JP2008300798A - Substrate conveying method, and substrate conveying device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a substrate conveying method and a substrate conveying device that improve conveyance precision of a substrate without increasing the number of sensors. <P>SOLUTION: The optical axis of a sensor 20 is tilted to a normal direction Z of the substrate S to make a higher detection point PS0 on the optical axis pass one point on an end surface of the substrate S. Further, a hand point is displaced in the normal direction Z to make a lower detection point PS1 on the optical axis pass the other point of the end surface of the substrate S. Then the center of the substrate S is computed using a higher distance based upon a detection result with respect to the higher detection point PS0 and a lower distance based upon a detection result with respect to the lower detection point PS1, and the center of the substrate S is conveyed to a target point. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a substrate transfer method and a substrate transfer apparatus.

  In a manufacturing apparatus for manufacturing a semiconductor device or a liquid crystal display, a system in which a plurality of process chambers are connected to one core chamber, that is, a so-called cluster type system, is widely used in order to improve productivity.

  The core chamber connected to the plurality of process chambers is generally formed in a regular polygonal column shape that connects each of the plurality of process chambers to each side surface, and a transfer robot for transferring the wafer is mounted therein. The transfer robot is disposed on the central axis of the core chamber and transfers the wafer to all the process chambers. The transfer robot has a hand for supporting the wafer, and moves the hand in the circumferential direction and the radial direction of the circumscribed circle of the core chamber. The wafer accommodated in the load lock chamber is supported by the hand of the transfer robot and transferred to the process chamber by the planar movement of the hand.

  In a cluster system, in order to give high reproducibility to the processing state of each process chamber, it is important to repeat accurate wafer conveyance to each process chamber. In order to improve the transfer accuracy, the transfer robot needs a technique for detecting the position of the wafer in the transfer process of the wafer and correcting the transfer state of the wafer based on the detection result. 2. Description of the Related Art Conventionally, in semiconductor device manufacturing apparatuses, proposals have been made to detect the center of a wafer in such a transfer process and improve the wafer transfer accuracy.

  In Patent Document 1, a sensor array including a plurality of sensors (for example, three sensors) is mounted on a core chamber, and each of the plurality of sensors is attached along a direction crossing the R direction. Each sensor of the sensor array is triggered by the end face of the wafer moving in the R direction, and outputs the position of the wafer related to this sensor trigger point. The transfer robot calculates the relative position of the wafer center with respect to the target point in response to the three output signals output from each sensor array, and moves the center of the wafer to the target point via the transfer robot. According to this, since the position of the wafer is detected using the wafer loading / unloading operation, the wafer position information can be obtained accurately without stopping the movement of the transfer robot.

In Patent Document 2, each sensor of the sensor array is attached along a direction crossing the circumferential direction. Each sensor of the sensor array is triggered by the end face of the wafer moving in the circumferential direction, and outputs the position of the wafer related to this sensor trigger point. According to this, it is possible to cause the sensor array to detect the end face of the wafer without separately performing the wafer loading / unloading operation, and the wafer position information can be obtained by a simpler method.
Japanese Patent Publication No. 7-27953 JP-A-6-224284

  In both Patent Documents 1 and 2, since the center position of one wafer is calculated using one sensor array, the number of sensor arrays must be increased in order to improve the wafer transfer accuracy. As a result, in Patent Documents 1 and 2, there is a problem that the number of members of the manufacturing apparatus is remarkably increased, resulting in a complicated apparatus configuration and high cost.

  The present invention has been made to solve the above-described problems, and provides a substrate transport method and a substrate transport apparatus that improve the transport accuracy of a substrate without increasing the number of sensors.

  In order to achieve the above object, the invention described in claim 1 is a substrate transport method for transporting a substrate supported by a hand to a target point, and whether or not the end surface of the substrate is on an optical axis. The optical axis of the sensor to be detected is tilted with respect to the normal direction of the substrate, the substrate is transported along a path through which one point of the end surface passes on the optical axis, and the one path The substrate is transported along another path that is displaced in the normal direction and passes the other point of the end face on the optical axis, and the center of the substrate is determined using the detection result relating to the one point and the other point. The gist is to calculate and transport the center of the substrate to the target point.

  According to the substrate transfer method of the first aspect, a plurality of different detection points on the end face of the substrate can be detected by one optical axis. Therefore, it is possible to improve the substrate transport accuracy without increasing the number of sensors.

  Invention of Claim 2 is the board | substrate conveyance method of Claim 1, Comprising: The said optical path is made to incline in the said normal line direction, and the said one path | route and the said other path | route are seen from the said normal line direction. The gist is to make the optical axes orthogonal to each other.

  According to the second aspect of the present invention, the positional relationship between the end surface of the substrate in the transport process and the optical axis can be made simpler. Therefore, the positions of a plurality of different detection points can be defined by simpler calculation.

  Invention of Claim 3 is a board | substrate conveyance method of Claim 1 or 2, Comprising: The said board | substrate is conveyed on the said optical axis along the said one path | route, and the said board | substrate on the said optical axis is said said The gist is that the sheet is transported along the other path by being displaced in the normal direction.

According to the invention described in claim 3, since the substrate is displaced on the optical axis, a plurality of different detection points can be continuously detected.
Invention of Claim 4 is a board | substrate conveyance method as described in any one of Claims 1-3, Comprising: The said other point is a several different point, and makes it a summary.

According to the fourth aspect of the present invention, the substrate transfer accuracy can be further improved by the number of other points.
In order to achieve the above-mentioned object, the invention according to claim 5 includes a transfer robot having a hand for supporting the substrate to transfer the substrate to a target point, and whether or not the end surface of the substrate is on the optical axis. A sensor for detecting whether or not, and a control means for driving and controlling the transfer robot in response to a detection result of the sensor, the sensor having an optical axis inclined with respect to a normal direction of the substrate, The control means relates to one path for passing one point of the end face on the optical axis, and another path for moving the other point of the end face on the optical axis by displacing from the one path in the normal direction. Generate route data, drive and control the transfer robot using the route data, calculate the center of the substrate in response to the detection result regarding the one point and the other point, and transfer the center of the substrate to the target point The gist is to make it.

  According to the substrate transfer apparatus of the fifth aspect, a plurality of different detection points on the end face of the substrate can be detected by one optical axis. Therefore, it is possible to improve the substrate transport accuracy without increasing the number of sensors.

A sixth aspect of the present invention is the substrate transfer apparatus according to the fifth aspect, wherein the optical axis is orthogonal to the one path and the other path as seen from the normal direction. And
According to the substrate transfer apparatus of the sixth aspect, the positional relationship between the end surface of the substrate in the transfer process and the optical axis can be made a simpler configuration. Therefore, the positions of a plurality of different detection points can be defined by simpler calculation.

  A seventh aspect of the present invention is the substrate transfer apparatus according to the fifth or sixth aspect, comprising a calibration substrate having a through hole in the center, and the transfer robot has the through hole at a reference position of a hand. The sensor detects whether or not the through hole is on the optical axis, and the control means drives the transport robot to cause the hand to repeat a plane motion and a lifting motion, and the sensor The gist is to associate the optical axis with the reference position of the hand in response to the detection result.

  According to the seventh aspect of the present invention, the optical axis can be associated with the reference position of the hand based on the detection result of the sensor. Therefore, the center of the substrate can be related to the reference position of the hand, and the center of the substrate can be transported to the target point with higher accuracy.

  As described above, according to the present invention, it is possible to provide a substrate transport method and a substrate transport apparatus that improve the substrate transport accuracy without increasing the number of sensors.

  Hereinafter, an embodiment embodying the present invention will be described below. First, a semiconductor device manufacturing apparatus 10 as a substrate transfer apparatus will be described. FIG. 1 is a plan view schematically showing the manufacturing apparatus 10 viewed from the normal direction of the substrate. 2A and 2B are a plan view and a side sectional view, respectively, showing the hand of the transfer robot.

  In FIG. 1, a manufacturing apparatus 10 is a cluster type system, and is connected to a core chamber 11, a pair of load lock chambers (hereinafter simply referred to as LL chambers) 12 connected to the core chamber 11, and the core chamber 11. And six process chambers 13.

  The core chamber 11 has a bottomed cylindrical chamber main body 11a formed in a regular octagonal columnar shape, and a regular octagonal columnar internal space (centered around the transfer center C of the chamber main body 11a) inside the chamber main body 11a ( Hereinafter, simply referred to as a transfer chamber 11s) is formed. The chamber body 11a is covered with a chamber lid (not shown) and maintains the vacuum state of the transfer chamber 11s.

  Each LL chamber 12 has an internal space (hereinafter simply referred to as a storage chamber 12s) in which a vacuum state can be maintained. Each storage chamber 12s has a cassette 12c that can store a plurality of substrates S, and a plurality of substrates S are stored in each slot of the cassette 12c. As the substrate S, for example, a circular substrate such as a silicon wafer or a ceramic substrate having a known diameter can be used. Each LL chamber 12 allows the transfer chamber 11s and the storage chamber 12s to communicate with each other in a releasable manner, and allows the substrate S to be transferred into and out of the transfer chamber 11s.

  Each process chamber 13 has an internal space (hereinafter simply referred to as a process chamber 13s) that can maintain a vacuum state. Each process chamber 13 has a substrate stage (not shown) in the processing chamber 13s, and performs various processes such as a cleaning process, a film forming process, and a heat treatment on the substrate S placed on the substrate stage. Each process chamber 13 allows releasable communication between the transfer chamber 11s and the processing chamber 13s to allow the substrate S to be loaded, and allows the substrate S to be transferred to the transfer chamber 11s after performing a predetermined process.

  A transfer point P is defined for each storage chamber 12s and each processing chamber 13s. Each transport point P is a target point for arranging the center of the substrate S, and is a point in a cylindrical coordinate system having the transport center C as an origin. In each process chamber 13, the center of the substrate S is arranged at the corresponding transfer point P, so that high reproducibility can be given to the corresponding processing operation.

  A transfer robot 15 for transferring the substrate S is mounted substantially at the center of the transfer chamber 11s. The transfer robot 15 is connected to the turning axis A that moves up and down in the normal direction of the substrate S, the arm 16 that turns around the turning axis A and moves straight in the radial direction D of the turning axis A, and the arm 16. And a hand 17.

  The arm 16 is drivably coupled to the output shaft of a pair of horizontal motors M1 (see FIG. 7) via a turning axis A. When each horizontal motor M1 rotates in the same direction, the arm 16 causes the hand 17 to linearly move along the radial direction D of the swivel axis A according to the circular coordinates with the conveyance center C as the origin. Further, when each horizontal motor M1 rotates in the opposite direction, the arm 16 turns the hand 17 in the turning direction θ of the turning axis A according to the circular coordinates with the conveyance center C as the origin.

  The turning axis A is drivingly connected to the output shaft of the lifting motor M2 (see FIG. 7). The swing axis A moves the swing axis A up and down along the normal direction Z of the substrate S when the lifting motor M2 rotates forward or reverse. That is, when the lifting motor M2 is driven to rotate, the arm 16 displaces the position of the hand 17 in the normal direction Z to a predetermined position, and executes the planar movement of the hand 17 at the position of the predetermined normal direction Z. Let

  In the present embodiment, the position in the normal direction Z is referred to as a height position. In the present embodiment, the radial direction D is a reciprocating direction along the diameter of the turning axis A, and the turning direction θ is a reciprocating direction along the circumference of the turning axis A.

  In FIG. 2, the hand 17 is formed in a hawk shape extending in the radial direction D, and four guide portions 17 b each having a substantially arc shape protruding from the upper surface 17 a are formed on the upper surface 17 a. Each guide portion 17b is formed on the same circle as viewed from the normal direction, guides the end surface of the substrate S to a predetermined region, and suppresses the positional deviation of the substrate S.

  Here, the center of the concentric circle drawn by each guide part 17b is called hand point 17P. A region of the upper surface 17a surrounded by each guide portion 17b is called a pocket. When the hand 17 accommodates the substrate S in the pocket and places the center of the substrate S at the hand point 17P, the hand 17 stabilizes the relative position of the substrate S with respect to the hand 17 and suppresses the positional deviation of the substrate S in the transport process. .

  An arcuate notch 18 that penetrates the hand 17 in the normal direction is formed on the pocket conveyance center C side. The notch 18 makes the end surface of the substrate S visible from the normal direction when the pocket supports the substrate S. As a result, the hand 17 exposes all the regions corresponding to the radial direction D and the turning direction θ in the end surface of the substrate S.

  The transfer robot 15 is taught the transfer center C and the transfer points P using the calibration substrate CS shown in FIG. The calibration substrate CS has a through hole CH having a predetermined inner diameter (for example, 1 mm) at the center, and when supported by the hand 17, the through hole CH is virtually associated with the hand point 17P. The position of the defined hand point 17P is physically defined.

The transport robot 15 moves the hand 17 in the radial direction D and the turning direction θ while supporting the calibration substrate CS, and moves the through hole CH directly above the teaching portion T. As the teaching portion T, a convex portion or a concave portion of the core chamber 11 that uniquely defines the conveyance center C, or a convex portion or a concave portion on the conveyance point P can be used. The transfer robot 15 stores the number of steps of each motor M1 as the posture of the arm 16 when the through hole CH is immediately above the teaching portion T, that is, when the hand point 17P is associated with the transfer center C. This teaches the transport center C, that is, the origin of polar coordinates. Further, when the hand point 17P coincides with the transfer point P, the transfer robot 15 stores the number of steps of each motor M1 as the posture of the arm 16, and thereby teaches the position of the transfer point P.

  By teaching the transfer center C and the transfer point P, the transfer robot 15 can transfer the hand point 17P to each target point in the circular coordinate system. When the center of the substrate S is the hand point 17P or when the center of the substrate S is corrected as the hand point 17P, the transfer robot 15 places the center of the substrate S on the target point with high accuracy. Can be made.

  3 and 4 are diagrams showing the sensor 20, respectively, a plan view seen from the normal direction Z of the substrate S and a side view seen from the radial direction D. FIG. In FIG. 3, the transport point P from which the substrate S is unloaded is referred to as a start point PA, and the transport point P as a carry-in destination is referred to as an end point PB. The hand point 17P when the hand 17 is drawn closest to the conveyance center C is referred to as a drawing point PC. A straight line connecting the start point PA and the pull-in point PC or a straight line connecting the end point PB and the pull-in point PC is referred to as a route RT.

  When transporting the substrate S from the start point PA to the end point PB, the transport robot 15 first transports the hand point 17P from the start point PA to the pull-in point PC along the route RT including the start point PA. Next, after the substrate robot S is turned at a predetermined turning angle, the transfer robot 15 transfers the hand point 17P from the pull-in point PC to the end point PB along the route RT including the end point PB.

  One sensor 20 for correcting the positional deviation of the substrate S is provided on each path RT. Each sensor 20 is an optical on / off sensor, and includes a pair of upper and lower light projecting units 20A and 20B sandwiching a transport plane (hereinafter simply referred to as a transport surface) of the substrate S. The light projecting unit 20A and the light receiving unit 20B are disposed outside the radial direction D of the hand 17 when viewed from the normal direction when the hand point 17P is conveyed to the drawing point PC.

  3 and 4, the light projecting unit 20A forms an optical axis that is in a plane orthogonal to the path RT and that is inclined at an inclination angle α with respect to the normal direction Z, and the laser is projected along the optical axis. L is emitted. The light receiving unit 20B is disposed on the optical axis formed by the light projecting unit 20A and receives the laser L transmitted from above.

  Each sensor 20 is turned off when the laser L for the light receiving unit 20B is blocked by the substrate S, and turned on when the laser L is not blocked by the substrate S. And each sensor 20 detects whether the end surface of the board | substrate S exists on an optical axis by each switching from an OFF state to an ON state, or switching from an ON state to an ob state.

Here, the point that blocks the laser L on the end surface of the substrate S is referred to as a detection point PS.
The transport robot 15 is taught the optical axis of each sensor 20. The transport robot 15 transports the hand 17 to the vicinity of the optical axis while supporting the calibration substrate CS, and blocks the laser L by the calibration substrate CS. Next, the transfer robot 15 causes the hand 17 to alternately repeat the turning of a predetermined turning angle and the straight movement of a predetermined distance until the through hole CH of the calibration substrate CS is positioned on the optical axis. When the through hole CH is positioned on the optical axis, the transfer robot 15
, The number of steps of each motor M1, M2 is stored as the posture of the arm 16, thereby teaching one point on the corresponding optical axis. The transport robot 15 raises and lowers the turning axis A and repeats the above teaching operation, and teaches a plurality of points on the optical axis, thereby teaching the position of the optical axis.

FIGS. 5 and 6 are views showing the transport process of the substrate S, respectively, a plan view seen from the normal direction Z and a side view seen from the radial direction D. FIG.
5 and 6 each show a transfer process in which the height position of the substrate S is different by the displacement amount H1. In each transport process, the relatively upper substrate S is indicated by a solid line as an upper substrate S0, and the lower substrate S is indicated by a two-dot chain line as a lower substrate S1. The virtual center of the upper substrate S0 is referred to as the upper center Sa0, and the virtual center of the lower substrate S1 is referred to as the lower center Sa1.

  5 and 6, the transfer robot 15 transfers the upper substrate S0 along the route RT, and passes one point on the optical axis through the end surface of the upper substrate S0. Further, the transfer robot 15 transfers the lower substrate S1 along the route RT, and passes the other point on the optical axis to the end surface of the lower substrate S1.

  Here, a point on the optical axis through which the end surface of the upper substrate S0 passes is referred to as an upper detection point PS0. Further, another point on the optical axis that passes through the end surface of the lower substrate S1 is referred to as a lower detection point PS1.

  When the end surface of the substrate S is detected by the upper detection point PS0, the transfer robot 15 detects the distance between the upper center Sa0 and the transfer center C as the upper distance D0 based on the position of the hand point 17P. Further, when the end surface of the substrate S is detected at the lower detection point PS1, the transfer robot 15 detects the distance between the upper center Sa0 and the transfer center C as the lower distance D1 based on the position of the hand point 17P. To do.

  The transfer robot 15 uses the detection results of the upper distance D0 and the lower distance D1, and sets the upper detection point PS0 viewed from the upper center Sa0 and the lower detection point PS1 viewed from the lower center Sa1, respectively, with the upper center Sa0 as the origin. Is converted into a plane coordinate system. At this time, the upper detection point PS0 and the lower detection point PS1 are points on the optical axis, respectively, and when the optical axis is taught to the transport robot 15, it is uniquely defined according to each path RT. The Therefore, in the planar coordinate system having the upper center Sa0 as the origin, the lower detection point PS1 is always separated from the upper detection point PS0 by H1 · tanα in the direction of the optical axis, that is, in the direction orthogonal to the radial direction D.

  The transfer robot 15 is a circle having the same radius as the radius Rs of the substrate S in the plane coordinate system having the upper center Sa0 as the origin, and the center coordinates of the circle passing through the two detection points PS0 and PS1. That is, the center coordinates of the substrate S are calculated.

  When there are two circles passing through the two detection points PS0 and PS1, the transfer robot 15 selects a circle according to the on / off state of the sensor 20. That is, the transfer robot 15 selects the circle closer to the transfer center C when the substrate S enters the laser L and the sensor 20 switches from the on state to the off state. On the other hand, when the substrate S is retracted from the laser L and the sensor 20 is switched from the off state to the on state, the transfer robot 15 selects a circle farther from the transfer center C, and the center coordinates of the substrate S are selected. Is calculated.

Then, the transfer robot 15 combines the displacement of the center coordinates viewed from the upper center Sa0 with the polar coordinates of the target point to obtain the corrected polar coordinates of the target point.
Accordingly, the transfer robot 15 can detect the end surface of the substrate S by a plurality of different detection points by using one sensor 20 by the amount that the substrate S is displaced along the normal direction Z. The conveyance accuracy can be improved.

Next, the electrical configuration of the manufacturing apparatus 10 will be described below. FIG. 7 is an electric block circuit diagram showing an electrical configuration of the manufacturing apparatus 10.
In FIG. 7, the control device 30 constituting the control means causes the manufacturing apparatus 10 to perform various processing operations such as the substrate S transfer processing and the substrate S film forming processing. The control device 30 includes an internal I / F 31 for receiving various control signals and a control unit 32 for executing various arithmetic processes. The control device 30 also includes a storage unit 33 for storing various data and various control programs, and an external I / F 34 for outputting various signals.

  The storage unit 33 stores the transfer program TP for correcting the position of the target point using the sensor 20 and executing the transfer process of the substrate S. The storage unit 33 stores position data IP related to the coordinates of each point and route data IR related to each route RT.

The position data IP is data relating to the coordinates of the transfer center C, the coordinates of the transfer points P, and the coordinates of the optical axes of the sensors 20 obtained by teaching the transfer robot 15.
The route data IR is data relating to the driving amount of each of the motors M1 and M2, and moves the hand point 17P by turning the hand 17 and moves the hand on the route RT connecting the selected transfer point P and the transfer center C. This is data for arranging the points 17P. Further, the route data IR causes the hand 17 to perform a linear motion and an up-and-down motion to move the hand point 17P along a route RT connecting the selected transfer point P and the transfer center C, and to the end surface of the substrate S. Data for passing the upper detection point PS0 and the lower detection point PS1.

  The control unit 32 reads the transfer program TP from the storage unit 33 and executes the transfer process of the substrate S according to the transfer program TP. That is, as shown in FIG. 3, when the controller 32 transports the substrate S on the start point PA to the end point PB, first, the control unit 32 sets the hand point 17P along the route RT connecting the start point PA and the pull-in point PC. A control signal for moving to the pull-in point PC is output. Next, the control unit 32 outputs a control signal for placing the hand point 17P on the route RT connecting the end point PB and the drawing point PC. Then, the control unit 32 outputs a control signal for moving the hand point 17P to the end point PB along the route RT connecting the end point PB and the drawing point PC.

  An input / output unit 35 is connected to the control device 30 via an internal I / F 31. The input / output unit 35 has various operation switches such as a start switch and a stop switch, and inputs data to be used by the manufacturing apparatus 10 for various processing operations to the control apparatus 30. For example, the input / output unit 35 inputs data related to the transport conditions of the substrate S, such as the radius Rs of the substrate S, the number of substrates S, the start point PA and the end point PB defined for each substrate S, to the control device 30. The input / output unit 35 includes a display unit such as a liquid crystal display, and displays the processing state of the conveyance process executed by the control device 30. The control device 30 receives various data input from the input / output unit 35 and causes the substrate S to be transferred under transfer conditions corresponding to the input data.

A sensor drive circuit 36 and a pair of motor drive circuits 37 and 38 are connected to the control device 30 via an external I / F 34.
The control device 30 outputs a drive control signal corresponding to the sensor drive circuit 36 to the sensor drive circuit 36. The sensor drive circuit 36 drives each sensor 20 in response to a drive control signal from the control device 30, and inputs a detection result from each sensor 20 to the control device 30. The control unit 32 receives the detection result from each sensor 20 via the sensor drive circuit 36, and executes the transfer process of the substrate S according to the transfer program TP.

The control device 30 outputs drive control signals corresponding to the motor drive circuits 37 and 38 to the motor drive circuits 37 and 38, respectively. The motor driving circuits 37 and 38 are connected to corresponding motors M1 and M2 and corresponding encoders E1 and E2, respectively. Each motor drive circuit 37, 38 rotates the corresponding motor M1, M2 forward or backward in response to the drive control signal from the control device 30, respectively, and moves the hand based on the detection signal from the corresponding encoder E1, E2. The moving amount and moving direction of the point 17P are calculated.

  When the sensor 20 detects the end face of the substrate S at the upper detection point PS0, the control device 30 calculates the coordinates of the hand point 17P via the motor drive circuits 37 and 38, and based on the coordinates of the hand point 17P. The upper distance D0 is calculated. When the sensor 20 detects the end face of the substrate S at the lower detection point PS1, the control device 30 calculates the coordinates of the hand point 17P via the motor drive circuits 37 and 38, and based on the coordinates of the hand point 17P. The lower distance D1 is calculated. And the control apparatus 30 calculates the center coordinate of the board | substrate S using the detection result of these high-order distance D0 and low-order distance D1, and obtains the corrected target point.

  As a result, the control device 30 can detect the end surface of the substrate S by a plurality of different detection points using one sensor 20 by the amount that the height position of the substrate S is displaced. Can be improved.

Next, a method for transporting the substrate S using the semiconductor device manufacturing apparatus 10 will be described below.
In the semiconductor device manufacturing apparatus 10, first, the substrate S is set in the cassette 12 c of the LL chamber 12. At this time, the substrate center of the substrate S is not strictly positioned at the transfer point P of the LL chamber 12, and the substrate center is displaced in the radial direction D from the transfer point P of the LL chamber 12.

  Next, data relating to the transport conditions of the substrate S is input to the control device 30 via the input / output unit 35, and an operation signal for starting substrate processing is input. The control device 30 receives the operation signal for starting the substrate processing, reads the transfer program TP from the storage unit 33, and starts the transfer processing of the substrate S according to the transfer program TP.

  The control device 30 transports the substrate S between transport points P having different height positions during the transport process of the substrate S. For example, the control device 30 causes the substrate S at the transfer point P (start point PA) of the LL chamber 12 to be transferred to the transfer point P (end point PB) of the process chamber 13 having a height position different from that of the start point PA.

  That is, the control device 30 causes the hand point 17P to move straight along the route RT connecting the starting point PA and the pull-in point PC via the motor drive circuits 37 and 38. Subsequently, the control device 30 turns the hand point 17P via the motor drive circuits 37 and 38 and arranges the hand point 17P on the route RT connecting the pull-in point PC and the end point PB. Then, the control device 30 moves the hand point 17P along the route RT connecting the pull-in point PC and the end point PB via the motor drive circuits 37 and 38, and corresponds the height position of the hand point 17P. It is displaced on the optical axis of the sensor 20 to correspond to the height position of the end point PB.

  During this time, the control device 30 receives the detection result from each sensor 20 via the sensor drive circuit 36, and whether or not the end face of the substrate S is detected at the upper detection point PS0, and the substrate S at the lower detection point PS1. It is determined whether an end face is detected.

When the sensor 20 detects the end surface of the substrate S at the upper detection point PS0, the control device 30 calculates the coordinates of the hand point 17P and calculates the upper distance D0 based on the coordinates of the hand point 17P. Further, when the sensor 20 detects the end face of the substrate S at the lower detection point PS1, the control device 30 calculates the coordinates of the hand point 17P and calculates the lower distance D1 based on the coordinates of the hand point 17P. Then, the control device 30 calculates the center coordinates of the substrate S each time using the detection results of the upper distance D0 and the lower distance D1, and calculates the coordinates of the corrected target point based on the center coordinates of the substrate S. Then, the hand point 17P is moved to the corrected target point.

According to the above embodiment, the following effects can be obtained.
(1) In the above embodiment, the optical axis of the sensor 20 is tilted with respect to the normal direction Z of the substrate S, and one point of the end surface of the substrate S is passed through the upper detection point PS0 on the optical axis. Further, the hand point 17P is displaced in the normal direction Z, and the other point of the end surface of the substrate S is passed to the lower detection point PS1 on the optical axis. Then, the center of the substrate S is calculated using the upper distance D0 based on the detection result of the upper detection point PS0 and the lower distance D1 based on the detection result of the lower detection point PS1, and the center of the substrate S is transported to the target point.

  Therefore, a plurality of different points on the end surface of the substrate S can be detected by one optical axis. Therefore, the conveyance accuracy of the substrate S can be improved without increasing the number of sensors 20.

  (2) In the above-described embodiment, the optical axis of the sensor 20 is inclined in the normal direction Z and is orthogonal to the path of the substrate S when viewed from the normal direction Z. Therefore, the positional relationship between the end surface of the substrate S in the transfer process and the optical axis can be made simpler, and the positions of a plurality of different detection points PS0 and PS1 can be detected by simpler calculation. Can be made.

  (3) In the above embodiment, the substrate S is transported on the optical axis along the path RT corresponding to the upper detection point PS0, the end surface corresponding to the upper detection point PS0 is detected, and then the substrate S is moved in the normal direction. The substrate S is displaced along the path RT corresponding to the lower detection point PS1, and the end surface corresponding to the lower detection point PS1 is detected. Therefore, since the substrate S is displaced on the optical axis, a plurality of different detection points PS0 and PS1 can be continuously detected.

In addition, you may implement the said embodiment in the following aspects.
In the above embodiment, only one lower detection point PS1 is detected. The configuration is not limited to this, and a plurality of lower detection points PS1 may be detected. According to this, the position of the substrate S can be detected with higher accuracy, and the transport accuracy of the substrate S can be further improved.

  In the above embodiment, the optical axis of the sensor 20 is orthogonal to the path RT. For example, as illustrated in FIG. 8, the optical axis of the sensor 20 may be inclined by the inclination angle β with respect to the radial direction D.

  At this time, as shown in FIGS. 9A and 9B, in the plane coordinate system having the upper center Sa0 as the origin, the lower detection point PS1 is always orthogonal to the radial direction D from the upper detection point PS0. In the direction of (H1 · tan α) · tan β. Therefore, when the center coordinates of the substrate S are calculated using a plane coordinate system with the upper center Sa0 as the origin, the distance between the upper detection point PS0 and the lower detection point PS1 is along the direction orthogonal to the radial direction D. (H1 · tan α) · tan β.

  In the above embodiment, the substrate S is embodied in a disk shape, but the present invention is not limited thereto, and for example, the substrate S may be embodied in a rectangular shape. That is, the substrate in the present invention only needs to have a shape that can calculate the position of the substrate using the detection position on the path.

  In the above embodiment, each sensor 20 is on a concentric circle centered on the transport center C, and only one sensor 20 is disposed for each transport point P. For example, each sensor 20 may not be arranged on a concentric circle centered on the conveyance center C, and one or more may be arranged for each conveyance point P. May be. That is, the present invention is not limited to the arrangement position and quantity of the sensor 20.

  In the above embodiment, the core chamber 11 is connected to the two LL chambers 12 and the six process chambers 13. However, the number of LL chambers 12 may be one or three or more, and the number of process chambers 13 may be five or less, or seven or more. In other words, the substrate transport apparatus of the present invention is not limited to the number and type of chambers, and may be any apparatus that transports a substrate to a target point along a predetermined path.

The top view which shows typically the manufacturing apparatus of a semiconductor device. (A), (b) is the top view and side sectional view which show a hand, respectively. The top view which shows the positional relationship of a sensor and a path | route. The side view which shows the positional relationship of a sensor and a board | substrate normal line. The top view which shows typically the conveyance process of a board | substrate. The side view which shows typically the conveyance process of a board | substrate. The electric block circuit diagram which shows the electric constitution of the manufacturing apparatus of a semiconductor device. The side view which shows the positional relationship of the sensor and board | substrate normal in the example of a change. (A), (b) is the top view and side view which show typically the conveyance process of the board | substrate in a modification, respectively.

Explanation of symbols

  S ... Substrate, Z ... Normal direction, CH ... Through hole, CS ... Calibration substrate, IR ... Path data, 15 ... Transfer robot, 17 ... Hand, 20 ... Sensor.

Claims (7)

A substrate transfer method for transferring a substrate supported by a hand to a target point,
Inclining the optical axis of the sensor for detecting whether or not the end face of the substrate is on the optical axis with respect to the normal direction of the substrate,
The substrate is transported along a path that allows one point of the end surface to pass on the optical axis, and is displaced in the normal direction from the path so that the other point of the end surface passes on the optical axis. Transport the substrate along another path,
Calculating the center of the substrate using the detection results for the one point and the other point, and transporting the center of the substrate to the target point;
A substrate carrying method characterized by the above. It is a board | substrate conveyance method of Claim 1, Comprising:
Tilting the optical axis in the normal direction, and making the optical axis orthogonal to the one path and the other path as seen from the normal direction;
A substrate carrying method characterized by the above. It is a board | substrate conveyance method of Claim 1 or 2, Comprising:
Transporting the substrate on the optical axis along the one path, transporting the substrate on the optical axis along the other path by displacing the substrate on the optical axis,
A substrate carrying method characterized by the above. It is a board | substrate conveyance method as described in any one of Claims 1-3,
The other points are a plurality of different points;
A substrate carrying method characterized by the above. A transport robot having a hand for supporting the substrate and transporting the substrate to a target point;
A sensor for detecting whether an end face of the substrate is on the optical axis;
And a control means for driving and controlling the transfer robot in response to the detection result of the sensor,
The sensor is
An optical axis inclined with respect to the normal direction of the substrate;
The control means includes
Generating path data relating to one path that passes one point on the end face on the optical axis and another path that is displaced in the normal direction from the one path and passes another point on the end face to the optical axis. ,
Driving and controlling the transfer robot using the path data, receiving a detection result relating to the one point and the other point, calculating a center of the substrate, and transferring the center of the substrate to the target point;
A substrate transfer device. It is a board | substrate conveyance apparatus of Claim 5, Comprising:
The optical axis is
Orthogonal to the one path and the other path when viewed from the normal direction,
A substrate transfer device. The substrate transfer apparatus according to claim 5 or 6,
A calibration substrate having a through hole in the center,
The transfer robot arranges the through hole at a reference position of a hand,
The sensor detects whether the through hole is on the optical axis;
The control means drives the transport robot to cause the hand to repeat a plane motion and a lifting motion, and associates the optical axis with a reference position of the hand in response to a detection result of the sensor;
A substrate transfer device.

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