JP2009016604A - Wafer transport device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a wafer transport device capable of preventing occurrence of trouble wherein the operation of a wafer transport system in a mini-environment facility is resultantly stopped by keeping transport accuracy of a wafer transport robot. <P>SOLUTION: This wafer transport device is composed by including: an mini-environmental housing forming a transport compartment of a wafer in its inside; the wafer transport robot movable in the transport compartment for transporting the wafer between a cassette part and a semiconductor manufacturing device by holding the wafer; a hand part installed in a wafer handling mechanism of the wafer transport robot for holding and moving the wafer; a detector arranged on the hand part for detecting a detection object; a reference slit arranged in the mini-environmental housing for defining references in a plurality of directions in the transport chamber where the wafer transport robot moves; and a controlling controller controlling the moving direction of the wafer transport robot based on the position of the reference slit of the detection object detected by the detector of the hand part. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a wafer transfer apparatus for transferring a semiconductor wafer.

  In equipment equipped with a local clean transfer chamber that supplies wafers to the semiconductor manufacturing equipment and discharges the processed wafers from the semiconductor manufacturing equipment (hereinafter abbreviated as "minien"), the main transfer of the wafer is the wafer taken out from the cassette. Is transported by the wafer transport robot and supplied to the semiconductor manufacturing apparatus, and the wafer processed and discharged by the semiconductor manufacturing apparatus is taken out, transported by the wafer transport robot, and stored in the cassette.

  In such a conventional mini-ene, when the wafer transfer robot constituting the wafer transfer system is worn at a plurality of movable parts, and the wear progresses, the transfer accuracy of the wafer transfer robot deteriorates. There is a possibility that the miniene wafer transfer system will be shut down.

  In the republished WO2003 / 022534 and JP-A-2005-142225, the wafer position is automatically and accurately taught to the robot that carries the wafer without relying on the operator's vision. There is disclosed a technique in which a teaching jig is provided at a position where the teaching tool is installed, and the teaching jig is detected by a transmission type sensor provided in a robot hand.

Republished WO2003 / 022534 JP 2005-142225 A

  Also in the techniques described in the re-published WO2003 / 022534 and JP-A-2005-142225, the wafer transfer robot that transfers the wafer advances the wear generated in the movable part in the same manner as the conventional technique described above. If the transfer accuracy deteriorates, the possibility that the mini-en wafer transfer system will be shut down cannot be avoided.

  An object of the present invention is to provide a wafer transfer apparatus capable of maintaining the transfer accuracy of a wafer transfer robot that transfers a wafer and avoiding the occurrence of problems that cause the miniene wafer transfer system to stop operating.

  The wafer transfer apparatus of the present invention stores a wafer to be supplied to a semiconductor manufacturing apparatus for processing a wafer, and stores a cassette section for storing a wafer processed and discharged by the semiconductor manufacturing apparatus, and one of the cassette sections. A mini-en housing that is attached to the side wall surface, the semiconductor manufacturing apparatus is attached to the other side wall surface opposite to the cassette unit to form a wafer transfer chamber, and the wafer stored in the cassette unit is gripped And a wafer handling robot having a wafer handling mechanism capable of moving between the cassette unit and the semiconductor manufacturing apparatus and moving in a transfer chamber formed in the mini-en housing, and a wafer handling mechanism of the wafer transfer robot A hand unit that is installed on the hand and moves the wafer by gripping it, A detector for detecting a detection object, a reference slit for setting a reference in a plurality of directions in the transfer chamber in which the wafer transfer robot moves in the mini-en housing, and a detection target detected by the detector of the hand unit And a controller for controlling a moving direction of the wafer transfer robot based on a position of a reference slit of the object.

  The wafer transfer apparatus of the present invention stores a wafer to be supplied to a semiconductor manufacturing apparatus for processing a wafer, and stores a cassette section for storing a wafer processed and discharged by the semiconductor manufacturing apparatus, and one of the cassette sections. A mini-en housing that is attached to the side wall surface, the semiconductor manufacturing apparatus is attached to the other side wall surface opposite to the cassette unit to form a wafer transfer chamber, and the wafer stored in the cassette unit is gripped And a wafer handling robot having a wafer handling mechanism capable of moving between the cassette unit and the semiconductor manufacturing apparatus and moving in a transfer chamber formed in the mini-en housing, and a wafer handling mechanism of the wafer transfer robot A hand unit that is installed on the hand and moves the wafer by gripping it, The direction of movement of the wafer transfer robot based on the position of the wafer detected by the detector for detecting the detection target, the wafer of the detection target stored in the cassette unit, and the detector provided in the hand unit It is characterized by having a control controller for controlling.

  ADVANTAGE OF THE INVENTION According to this invention, the wafer conveyance apparatus which can maintain the conveyance precision of the wafer conveyance robot which conveys a wafer, and can avoid generation | occurrence | production of the malfunction which a miniene wafer conveyance system stops operation | movement is realizable.

  A wafer transfer apparatus according to an embodiment of the present invention will be described below with reference to the drawings.

  FIG. 1 is a perspective view showing a schematic configuration of a wafer transfer apparatus according to an embodiment of the present invention.

  In FIG. 1, in a wafer transfer apparatus for supplying a wafer 6 to a semiconductor manufacturing apparatus 1 and discharging the wafer 6 processed or inspected by the semiconductor manufacturing apparatus 1 from the semiconductor manufacturing apparatus 1, the main transfer is the wafer. The wafer 6 is taken out from the stored cassette 5 and supplied to the semiconductor manufacturing apparatus 1. When the predetermined processing of the wafer 6 is completed in the semiconductor manufacturing apparatus 1, the processed wafer 6 discharged from the semiconductor manufacturing apparatus 1 is taken out. It is configured to be stored in the cassette 5.

  The equipment for carrying the wafer under the local clean having the above-described configuration is called a mini-en.

  Next, a detailed description will be given of the configuration of a miniene serving as a wafer transfer apparatus according to an embodiment of the present invention. As shown in FIG. 1, the miniene includes a miniene housing 3, a fan filter unit (FFU) 7, and a sample. A load port unit 4 serving as a transfer port, a semiconductor manufacturing apparatus 1 that performs predetermined processing or inspection on the wafer 6, a pre-aligner 11 that is installed inside the mini-en housing 3 and aligns the wafer 6, and a mini-en housing 3 is provided with a wafer transfer robot 9 that moves the transfer chamber inside 3 and transfers the wafer 6, and a controller 2 that controls transfer of the wafer transfer robot 11 and other main equipment.

  The mini-en housing 3 covers the outside with a fixed plate (exterior cover), and forms a transfer chamber in a space isolated from the outside.

  The mini-en housing 3 also serves as a load port unit 4 and a mounting unit for the semiconductor manufacturing apparatus 1.

  The fan filter unit (FFU) 7 is composed of a blower fan and a filter. The fan filter unit (FFU) 7 is installed on the top of the mini-en housing 3 and flows down the clean air to the transfer chamber inside the mini-en housing 3 so that the mini-en housing 3 A clean environment is realized in the transfer chamber.

  The load port unit 4 serving as a sample transport port mainly has a sealed container fixing base and a container opening / closing function. The load port 4 is installed at a plurality of locations in the mini-en housing 3 to be connected to the semiconductor manufacturing apparatus 1. It plays the role of the sample transport port of the mini-en housing 3.

  The pre-aligner 11 is installed inside the mini-en housing 3 and has a mechanism for aligning the orientation flat and notch of the wafer 6 in a certain direction. The wafer 6 taken out from the cassette 5 is transported by the wafer transport robot 9. Before being supplied to the semiconductor manufacturing apparatus 1, the alignment is performed.

  The controller 2 communicates with the semiconductor manufacturing apparatus 1 and controls each mechanism constituting the miniene, and collectively controls the miniene transport system.

  The wafer transfer robot 9 has a wafer handling mechanism 15 that performs horizontal operation, vertical operation, and swivel operation of a hand 20 that holds the wafer 6 in order to mainly transfer the wafer 6, and moves inside the mini-en housing 3. The wafer 6 is transported between the load port unit 4 and the semiconductor manufacturing apparatus 1.

  2 includes a wafer handling mechanism 15 installed on an upper portion of a wafer transfer robot 9 disposed inside the mini-en housing 3 and a hand 20 for holding the wafer 6 constituting the wafer handling mechanism 15. The configuration of the wafer transfer robot 9 is shown.

  The wafer transfer robot 9 is attached to a robot travel axis (Y-axis drive unit) 23 that moves laterally (horizontal operation) installed on the side surface inside the mini-en housing 3, and is connected to the robot travel axis 23. By driving the AC servo motor 24, the wafer transfer robot 9 can move in the horizontal direction (Y-axis direction) along the robot travel axis 23 in the mini-en housing 3.

  Further, a wafer handling mechanism 15 having the configuration shown in FIG. 2 is provided on the upper portion of the wafer transfer robot 9, and this wafer handling mechanism 15 has a Z-axis for moving the hand 20 holding the wafer 6 in the up-and-down direction. The drive unit 22, the θ-axis drive unit 25 that moves the hand 20 in the rotational direction, the R-axis drive unit 26 that moves the hand 20 horizontally in the expansion / contraction direction of the arm 21, and the reversing shaft that can turn the wafer 6 upside down. The robot arm 21 including the driving unit 27 is provided.

  By providing the wafer handling mechanism 15 in the wafer transfer robot 9, the robot arm 21 is driven based on a control command from the controller 2, and the hand 20 is moved over the entire transfer chamber inside the mini-en housing 3. It can be moved to a position and positioned.

  The hand 20 provided in the arm 21 of the wafer handling mechanism 15 provided in the wafer transfer robot 9 is formed in a Y shape so as to hold or suck the wafer 6 as shown in FIG. A reflection type sensor 31 having a detection unit 32 and a reflection type sensor 37 having a detection unit 36 are installed at the Y-shaped tip of the hand 20.

  A reflective sensor 31 provided at one Y-shaped tip of the hand 20 and one transmissive sensor 33 having a light projecting unit 34 are provided at the other Y-shaped tip of the hand 20. 37 and the other transmission type sensor 33 having the light receiving part 35 are arranged so as to be spaced apart from each other.

The reflection type sensor 31 and the reflection type sensor 37 installed at the Y-shaped tip of the hand 20 reflect the light emitted from the detection unit 32 and the detection unit 36 by the wafer 6 or the like serving as a detection body. It is a sensor that detects the presence or absence of a wafer 6 or the like as a detection body by detecting light reflected from the body by the light receiving unit 32 and the detection unit 36.
In addition, the transmission sensor 33 installed at the Y-shaped tip of the hand 20 blocks the light emitted from the light projecting unit 34 by the wafer 6 or the like serving as a detection body, and changes in the amount of light caused by the detection body are detected by the light receiving unit 35. It is a sensor that detects the presence or absence of a wafer 6 or the like that becomes a detection body by detecting.

  The reflection type sensor 31 and the reflection type sensor 37 are attached to the Y-shaped tip portion of the hand 20 so as not to obstruct the gripping or suctioning of the wafer 6.

  Further, the reflection type sensors 31 and 37 immediately before the wafer 6 is to be gripped or sucked, and the Y of the hand 20 in the region where the wafer 6 can be detected even if the arm 21 and the hand 20 of the wafer handling mechanism 15 are moving. Attach to the position of the tip of the letter.

  Further, since the light amount of the transmissive sensor 33 is changed by the detection body blocking the light emitted from the light projecting unit 34 of the transmissive sensor 33, the change of the light amount is detected by the light receiving unit 35 of the transmissive sensor 33. It is a sensor which detects and detects the presence or absence of a detection body.

  The two transmission sensors 33 arranged so as to be opposed to each other are attached to the Y-shaped tip of the hand 20 as much as possible, and the light projecting portion 34 of one transmission sensor 33 and the other transmission sensor 33 are attached. The distance between the light receiving unit 35 and the light receiving unit 35 is reliably detected based on the detection distance specification of the transmissive sensor 33, and is in contact with the cassette 5 storing the wafer 6 and the wafer 6. It is set to be a distance that does not.

  FIG. 4 shows an external view of the reference slit 41 installed on the inner wall surface of the mini-en housing 3.

  The reference slit 41 is arranged along each axis (the Y axis along the horizontal robot travel axis, the Z axis along the vertical direction, and the direction in which the hand expands and contracts) on which the wafer handling mechanism 15 installed in the wafer transfer robot 9 moves. Reflective sensors 31 and 37 provided on the Y-shaped tip of the hand 20 provided in the wafer handling mechanism 15 of the transfer robot 9 with the R axis and the θ axis along the rotation direction of the hand, It is a rectangular parallelepiped of a size that can be detected by the transmission sensor 33 and does not become an obstacle when the hand 20 transports the wafer 6.

  4, the reference slit 41 is attached to the inner wall surface of the mini-en housing 3 so that the longitudinal direction of the reference slit 41 is along the R axis.

  The reference slit 41 is formed of a structure or material that is not damaged even if the hand 20 comes into contact. For example, the slit 41 is attached to the mini-en housing 3 with a spring or the like interposed therebetween, and the outer surface of the reference slit 41 is made of silicon or the like. It is covered with an elastic material that is a shock absorbing material.

  The reference slit 41 is fixed to the inner wall surface of the mini-en housing 3 with bolts or screws (not shown), and the reference slit 41 is attached to each axis (Y axis) on which the wafer handling mechanism 15 moves. , Z axis, θ axis, and R axis) can be finely adjusted.

  The reference slit 41 can be attached to a plurality of desired positions inside the mini-en housing 3 as necessary.

  The reference slit 41 is an axis (Y axis, Z axis, θ axis, R axis) of the reference slit 41 attached to the inside of the mini-en housing 3 as in the example of the attachment position of the reference slit 41 shown in FIG. Is detected by the reflection type sensors 31 and 37 and the transmission type sensor 33 provided on the hand 20 of the wafer handling mechanism 15 provided in the wafer transfer robot 9, so that the wafer 6 can be transferred to any position that does not hinder the transfer. A reference slit 41 is attached.

  At the attachment position of the reference slit 41 shown in FIG. 5, the rectangular parallelepiped of the reference slit 41 with respect to the inner wall surface of the mini-en housing 3 opposite to the outer wall surface of the mini-en housing 3 to which the load port 4 is attached. Are attached in a direction perpendicular to the right-angle R-axis.

  Next, the transfer of the wafer 6 that is transferred to the transfer chamber inside the mini-en housing 3 by the wafer transfer robot 9 will be described.

  1 and 2, a wafer transfer robot 9 that moves a wafer 6 accommodated in a cassette 5 installed in the load port unit 4 in a transfer chamber inside the mini-en housing 3 based on a control command from the controller 2. And is taken out from the cassette 5 and transferred to a pre-aligner 11 installed inside the mini-en housing 3, and the wafer 6 is aligned by the pre-aligner 11.

  Next, the wafer 6 aligned by the pre-aligner 11 is transferred again to the transfer chamber inside the mini-en housing 3 by the wafer transfer robot 9 based on a control command from the controller 2, and through the opening formed in the semiconductor manufacturing apparatus 1. In order to supply the wafer 6 to the semiconductor manufacturing apparatus 1, the wafer 6 is transferred to a wafer supply position 10 installed in the semiconductor manufacturing apparatus 1.

  The wafer 6 transferred from the wafer supply position 10 to the semiconductor manufacturing apparatus 1 is subjected to a desired processing or inspection process in the semiconductor manufacturing apparatus 1.

  Then, in order to discharge the wafer 6 processed in the semiconductor manufacturing apparatus 1 through another opening formed in the semiconductor manufacturing apparatus 1 from the semiconductor manufacturing apparatus 1, the processing is performed from the wafer discharge position 8 installed in the semiconductor manufacturing apparatus 1. A load port attached to the mini-en housing 3 by holding and taking out the finished wafer 6 by a wafer transport robot 9 operated based on a control command from the controller 2, transferring the transport chamber inside the mini-en housing 3. A series of transporting processes of the wafer 6 is completed by transporting and storing it in the cassette 5 installed on the upper part of the unit 4.

  Next, a method for self-diagnosis of the transfer accuracy in the wafer transfer apparatus described above will be described below.

  A method for self-diagnosis of the transfer accuracy shown in FIG. 6 will be described according to the procedure shown in the flowchart.

  In FIG. 6, first, in step 301 for adjusting and confirming the reference slit, which is performed first when performing self-diagnosis of the transfer accuracy in the wafer transfer apparatus, the operator sets the reference slit 41 in the cassette 5, the mini-en housing 3, the pre-slot. It is visually confirmed that the aligner 11, the wafer supply position 10 of the semiconductor manufacturing apparatus 1 and the wafer discharge position 8 of the semiconductor manufacturing apparatus 1 are positioned as intended.

  As shown in FIG. 5, with respect to the attachment position of the reference slit 41 installed inside the wall surface of the mini-en housing 3, the operator attaches the cassette 5 to the wall surface inside the mini-en housing 3 to which the load port unit 4 installed on the cassette 5 is attached. On the other hand, it is visually confirmed that the rectangular parallelepiped reference slits 41 are arranged at right angles so that the longitudinal directions thereof are orthogonal to each other.

  When the position of the reference slit 41 needs to be adjusted, the worker adjusts the position of the reference slit 41 in an adjustable work environment.

  In step 302 for inputting the initial parameters, the diagnosis cycle, and the allowable range, the operator sets each axis (Y axis, Z axis, θ axis, R axis) on which the reference slit 41 attached to the inner wall surface of the mini-en housing 3 is located. Are input to the controller 2 as initial parameters.

  This initial parameter is a predicted value obtained from a value or a dimension value measured at the time of manufacturing the mini-en conveying system.

  In addition, the controller 2 inputs a cycle for performing self-diagnosis of the wafer transfer accuracy by the wafer transfer robot 9 and a diagnosis timing and an allowable range of the transfer system at the time of diagnosis.

  Next, in the step from the reference slit Z-axis detection step 303 to the reference slit R-axis detection step 303 to the reference slit θ-axis and Y-axis detection step 305, the input is performed in step 302. Based on the initial parameters, the drive unit of the wafer handling mechanism 15 provided in the wafer transfer robot 9 is driven by the control command from the controller 2 to move the hand 20, and the Y-shaped tip of the hand 20 is moved. The position of each axis (Y axis, Z axis, θ axis, R axis) of the reference slit 41 is detected by the installed reflection type sensors 31 and 37 and the transmission type sensor 33.

  In step 303 for detecting the Z axis of the reference slit, the position of the coordinate 71 on the Z axis of the reference slit 41 is detected as shown in FIG.

  That is, the AC servo motor 24 is driven by a control command from the controller 2 to drive the Y-axis drive unit 23 of the wafer transfer robot 9, and the transfer robot 9 is moved in the transfer chamber inside the mini-en housing 3 to move the wafer. The position of the hand 20 provided in the wafer handling mechanism 15 of the transfer robot 9 is positioned at the coordinate 73 on the Y axis of the reference slit 41 obtained from the parameters.

  Next, according to a control command from the controller 2, the Z-axis drive unit 22 of the wafer transfer robot 9 is driven to move the hand 20 upward and downward, and the position of the hand 20 is higher than the position of the reference slit 41. Position it so that it is located at the coordinate 70 on the Z-axis of the hand before sensing.

  Next, based on a control command from the controller 2, the θ-axis drive unit 25 of the wafer transfer robot 9 is moved to move the hand 20 provided in the wafer handling mechanism 15 in the rotational direction, and the position where the position of the hand 20 is obtained from the parameters. The slit 41 is positioned so as to be positioned at a coordinate 74 on the θ axis.

  Next, the R-axis drive unit 26 of the wafer transfer robot 9 is driven by a control command from the controller 2 to move the hand 20 provided in the wafer handling mechanism 15 horizontally in the extending / contracting direction of the arm 21, thereby leading the tip of the hand 20. The transmission type sensor 33 and the reflection type sensors 31 and 37 mounted at a distance from each other are positioned so as to be positioned at a coordinate 75 on the R axis of the reference slit obtained from a parameter capable of detecting the reference slit 41.

  Next, according to a control command from the controller 2, the Z-axis drive unit 22 of the wafer transfer robot 9 is driven to move the hand 20 provided in the wafer handling mechanism 15 downward in the vertical direction and is mounted on the tip of the hand 20. The position of the coordinate 71 on the Z-axis, which is the position of the reference slit 41 in the process of moving the transmitted-type sensor 33 to the coordinate 72 on the Z-axis of the sensing hand below the reference slit 41, is determined by the transmission sensor 33. To detect.

  Then, the Z-axis encoder value of the coordinate 71 on the Z-axis of the position of the reference slit 41 detected by the transmission type sensor 33 installed in the hand 20 is stored in the controller 2 as the Z-axis detection value of the reference slit 41.

  Next, in step 304 for detecting the R axis of the reference slit, as shown in FIG. 8, a coordinate 81 on the R axis of the detected reference slit which is the position of the end of the reference slit 41 in the longitudinal direction is detected.

  That is, the wafer handling mechanism 15 of the wafer transfer robot 9 is provided in the same manner as the step 303 of detecting the Z axis of the reference slit by driving the Y axis drive unit 23 of the wafer transfer robot 9 according to the control command from the controller 2. The position of the hand 20 is positioned at the coordinate 73 on the Y axis.

  Then, the position of the hand 20 of the wafer transfer robot 9 is set to the position of the coordinate 74 on the θ axis of the reference slit in the same manner as in step 303 for detecting the Z axis of the reference slit by driving the θ axis drive unit 25 of the wafer transfer robot 9. Position so that

  The hand 20 is provided so that the Z-axis drive unit 22 of the wafer transfer robot 9 is driven so that the position of the reference slit 41 can be detected by the transmission sensor 33 installed at the Y-shaped tip of the hand 20. The hand 20 installed on the arm 21 of the wafer handling mechanism 15 is positioned at the coordinate 80 on the Z-axis of the reference slit obtained from the parameters.

  Then, the R-axis drive unit 26 of the wafer transfer robot 9 is driven to expand and contract the arm 21 of the wafer handling mechanism 15, and the hand 20 installed on the arm 21 is moved to the coordinate 75 on the R-axis, so that the reference slit 41 A coordinate 81 on the R axis, which is the tip position in the longitudinal direction, is detected by a transmission type sensor 33 installed at the Y-shaped tip of the hand 20.

  Then, the R-axis encoder value of the coordinate 81 on the R-axis at the position of the reference slit 41 detected by the transmission type sensor 33 of the hand 20 is stored in the controller 2 as the R-axis detection value.

  Next, in step 305 for detecting the θ-axis and Y-axis of the reference slit, the hand 20 of the wafer transfer robot 9 is moved in the rotational and lateral Y-axis directions in accordance with a control command from the controller 2 as shown in FIG. In addition, the coordinates 96 on the θ-axis and the coordinates 73 on the Y-axis, which are the positions of the reference slit 41, are respectively detected.

  First, in accordance with a control command from the controller 2, the θ axis driving unit 25 provided in the wafer handling mechanism 15 of the wafer transfer robot 9 is driven to move the hand 20 in the rotation direction, and the step of detecting the Z axis of the reference slit described above is performed. Similar to 303, the position of the hand 20 is positioned at the coordinate 74 on the θ axis of the reference slit 41.

  Next, the Z-axis drive unit 22 of the wafer transfer robot 9 is driven to move the hand 20 in the vertical Z-axis direction, and the reflective sensor 31 or 37 provided at the Y-shaped tip of the hand 20 serves as a reference. The lower surface of the slit 41 is positioned so as to be positioned at a coordinate 92 on the Z-axis that is a height at which it can be detected.

  Next, the R-axis drive unit 26 of the wafer transfer robot 9 is driven to move the hand 20 in the R-axis direction, which is the expansion / contraction direction of the arm 21, and each detection unit of the reflective sensors 31 and 37 provided on the hand 20. 32 and 36 are moved to the position of the coordinate 75 on the R axis which is the position of the reference slit 41.

  Next, the Y-axis drive unit 23 of the wafer transfer robot 9 is driven to move in the lateral Y-axis direction, and the detection units 32 of the reflective sensors 31 and 37 provided at the Y-shaped tip of the hand 20 36 is moved to the position of the coordinate 73 on the Y axis which is the position of the reference slit 41.

  The Y-axis drive unit 23 that moves the wafer transfer robot 9 in the Y-axis direction can detect the end surface of the reference slit 41 on the Y-axis by the reflective sensors 31 and 37 provided at the Y-shaped tip of the hand 20. The Y-axis encoder value in which the distance 90 from the coordinate 73 on the Y-axis to the one end face of the reference slit 41 and the distance 91 from the other end face are captured in advance in the controller 2 by moving in the + direction−. Calculate based on

  Then, the R-axis drive unit 26 of the wafer transfer robot 9 is driven to move in the R-axis direction which is the expansion / contraction direction of the arm 21, and the detection units 32 and 36 of the reflective sensors 31 and 37 provided on the hand 20 are used as reference slits. It is moved to the position of the coordinate 93 on the R axis which is the position of 41.

  Similarly, the Y-axis drive unit 23 that moves the wafer transfer robot 9 in the Y-axis direction is moved in the + direction−direction so as to detect the end face of the reference slit 41 on the Y-axis, and the reference slit is determined from the coordinate 73 on the Y-axis. A distance 94 to one end face 41 and a distance 95 to the other end face are calculated and obtained based on the Y-axis encoder value taken in the controller 2 in advance.

  A coordinate 96 on the θ-axis which is the position of the reference slit 41 is obtained from the difference between the distance 90 and the distance 95 or the difference between the distance 91 and the distance 94 and stored in the controller 2 as a detected value of the θ-axis of the reference slit 41.

  Then, the θ axis driving unit 25 is driven to move the hand 20 to the position of the coordinate 96 on the θ axis, and the values of the distance 90 and the distance 95 or the distance 91 and the distance 94 become equal within the allowable range. The position of one end face of the reference slit 41 is detected at that position, and the Y-axis encoder value at the detected position is stored in the controller 2 as the Y-axis detection value of the reference slit 41.

  Next, in the reference parameter registration step 308, when the reference parameter is set, the detection operation from the reference slit Z-axis detection step 303 to the reference slit θ-axis and Y-axis detection step 305 is repeated two or more times. For each axis of the slit 41, the controller 2 determines the root mean square from the entire difference between the initial parameter and the detected value at each time.

  The controller 2 evaluates the error of the detected value of each axis of the reference slit 41 by the calculated root mean square and stores the corrected value in the controller 2 as each axis reference parameter.

  Then, the detection operation from the reference slit Z-axis detection step 303 to the reference slit θ-axis and Y-axis detection step 305 is performed once again, and the permissible range between the detection value of each axis of the reference slit 41 and the reference parameter. And the reference parameter is registered in the controller 2.

  Next, in step 309 for starting the conveyance accuracy self-diagnosis, the initial parameters and the diagnostic cycle for determining the time when the mini-en conveying system is operating or when the cassette 5 is replaced or set, the diagnostic cycle input in step 302 for inputting the allowable range, Based on the diagnosis time (periodically), the detection operation from the reference slit Z-axis detection step 303 to the reference slit θ-axis and Y-axis detection step 305 is performed to detect the coordinates of the reference slit 41.

  In step 310 for determining whether the detected value is within the allowable range, the detected value of the reference slit 41 detected by the controller 2 is compared with the reference parameter registered in the reference parameter registration step 308.

  If the coordinates of the reference slit 41 can be detected within the allowable range, the process proceeds to an OK display step 311 to display the transfer accuracy OK for each axis of the reference slit 41 on a monitor such as a control panel or a host device. If there is an axis detected as follows, the process proceeds to a warning display step 312 to display a warning of an axis outside the allowable range, and the self-diagnosis of the conveyance accuracy in the mini-en conveying system is completed.

  Steps 309 for determining the Z-axis detection of the reference slit to determining whether to start the self-diagnosis for conveyance accuracy are programmed in advance in the controller 2 and automatically performed.

  Therefore, according to the wafer transfer apparatus of the embodiment of the present invention described above, since the transfer accuracy is self-diagnosis periodically during the operation of the wafer transfer system, the transfer robot is caused by factors such as wear of movable parts of the equipment of the transfer robot 9. It is possible to find out early the occurrence of misalignment in positioning reproducibility of each axis.

  In addition, it is possible to perform stoppage due to failure of the wafer transfer robot, avoidance or prevention of wafer breakage, and preventive maintenance.

  In addition, by registering the reference parameters for comparison of transfer accuracy under the same conditions as during self-diagnosis when installing the wafer transfer device, it is possible to accurately compare with the transfer accuracy at the start of operation of the wafer transfer system. I can do it.

  In addition, since it is not necessary for the worker to check the transfer chamber by stopping the wafer transfer device that operates for 24 hours in order to confirm the accuracy of the movement of the wafer transfer robot, it is possible to avoid a situation that hinders online work.

  In addition, by displaying the diagnosis result of the transfer accuracy for each axis that is the moving direction of the wafer transfer robot, it is possible to identify the cause and location of deviation in positioning reproducibility due to wear of moving parts at an early stage. Even when the parts need to be replaced, it is possible to shorten the time required for the replacement.

  Next, a method for teaching the wafer position in the wafer transfer apparatus will be described below.

  Regarding the method for teaching the wafer position in the wafer transfer apparatus shown in FIG. 10, the method for teaching the wafer position will be described according to the procedure shown in the flowchart.

  In FIG. 10, in the first step 101 for installing the reference wafer, the worker places the wafer 6 on the center stage inside the cassette 5 in which the wafer 6 serving as a teaching reference is attached to the outside of the wall surface of the mini-en housing 3. The notch is hidden behind the side of the cassette 5 and stored.

  The stage inside the cassette 5 on which the wafer 6 is placed may be arbitrary, but here, a case where it is placed at the center stage in order to reduce teaching errors will be described.

  Next, in the confirmation step 102 in the θ-axis direction, as shown in FIG. 5, the worker installs the cassette 5 on the upper side of the longitudinal direction of the reference slit 41 of the rectangular parallelepiped installed inside the wall surface of the mini-en housing 3. Then, it is visually confirmed that they are arranged at right angles so as to be orthogonal to the wall surface of the mini-en housing 3 which is the mounting surface of the load port 4 attached to the outside of the wall surface of the mini-en housing 3.

  Since the reference slit 41 is installed inside the wall surface of the mini-en housing 3 as in the mounting example shown in FIG. 5 and the reference slit 41 is taught in advance, the θ axis is at a relative position with respect to the reference slit 41. Satisfies the required straightness.

  In step 103 for inputting initial parameters, the operator inputs the coordinate values of the respective axes (Y axis, Z axis, θ axis, R axis) on which the reference wafer 6 is positioned to the controller 2 as initial parameters.

  This initial parameter is a value obtained by predicting the position of the reference wafer 6 accommodated in the cassette 5 from the values and dimension values measured at the time of manufacturing the mini-en transport system.

  By the confirmation step 102 in the θ-axis direction, the initial parameter regarding the θ-axis becomes the reference parameter.

  Next, from the step 104 for detecting the reference wafer Z-axis to the step 105 for detecting the R-axis and Y-axis of the reference wafer, the wafer handling mechanism provided in the transfer robot 9 based on the initial parameters according to the control command from the controller 2. The driving unit 20 is driven to move the hand 20, and each axis (Y axis) of the reference wafer 6 is reflected by the reflection type sensors 31 and 37 and the transmission type sensor 33 installed at the Y-shaped tip of the hand 20. , Z axis, and R axis) are detected.

  In step 104 of detecting the reference wafer Z-axis, the position of the Z-axis coordinate 111 of the reference wafer 6 is detected as shown in FIG. 11 in the same manner as the method of detecting the reference slit 41.

  That is, the AC servo motor 24 is driven by a control command from the controller 2 to drive the Y-axis drive unit 23 of the wafer transfer robot 9, and the transfer robot 9 is moved in the transfer chamber inside the mini-en housing 3 to move the wafer. The position of the hand 20 provided in the wafer handling mechanism 15 of the transfer robot 9 is positioned so as to be positioned at the coordinate 113 on the Y axis of the reference wafer 6 obtained from the parameters.

  Next, in accordance with a control command from the controller 2, the Z-axis drive unit 22 of the wafer transfer robot 9 is driven to move the hand 20 upward and downward, and the position of the hand 20 is sensed above the position of the reference wafer 6. Position it so that it is located at the Z-axis coordinate 110 of the previous hand.

  Next, the θ axis driving unit 25 of the wafer transfer robot 9 is driven by the control command from the controller 2 to move the hand 20 in the rotation direction, and the position of the hand 20 is obtained on the θ axis of the reference wafer 6 obtained from the parameters. Position it so that it is located at the coordinates 114.

  Next, the R-axis drive unit 26 of the wafer transfer robot 9 is driven by a control command from the controller 2 to move the hand 20 provided in the wafer handling mechanism 15 horizontally in the extending / contracting direction of the arm 21, thereby leading the tip of the hand 20. Coordinates on the R-axis obtained from the parameters at which the position of the transmission type sensor 33 and the reflection type sensors 31 and 37 mounted at a distance from each other can be detected and the reference wafer 6 is not damaged. 115 to be positioned.

  Next, in accordance with a control command from the controller 2, the Z-axis drive unit 22 of the wafer transfer robot 9 is driven to move the hand 20 downward in the vertical direction. The position of the coordinate 111 on the Z axis, which is the position of the reference wafer 6, is detected by the transmission sensor 33 in the process of moving the hand below the sensor 6 to the coordinate 112 on the Z axis.

  Then, the Z-axis encoder value of the coordinate 111 on the Z-axis of the position of the reference wafer 6 detected by the transmission type sensor 33 installed on the hand 20 is stored in the controller 2 as the Z-axis detection value of the reference wafer 6.

  Since the shape of the cassette 5 that stores the wafer 6 is defined, the position of all the wafer storage stages of the cassette 5 is calculated from the position (coordinate 111 on the Z axis) where the reference wafer 6 is detected. .

  If necessary, all the positions of the wafers 6 stored in all stages of the cassette 5 may be detected.

  Next, in step 105 of detecting the R axis and Y axis of the reference wafer, as shown in FIG. 12, the position of the coordinate 123 on the R axis and the position of the coordinate 113 on the Y axis as the position of the reference wafer 6 are detected. To do.

  That is, based on the Z-axis upper coordinate 111 detected in the step 104 for detecting the Z-axis of the reference wafer, the Z-axis drive unit 22 of the wafer transfer robot 9 is driven by the control command from the controller 2 to move the hand 20 up and down. The position of the reference wafer 6 is determined so that the position of the reference wafer 6 can be detected by the reflective sensors 31 and 37 provided at the Y-shaped tip of the hand 20.

  Next, the θ axis driving unit 25 of the wafer transfer robot 9 is driven to rotate the hand 20 so that the position of the hand 20 becomes the position of the coordinate 114 on the θ axis of the reference wafer 6. Position.

  Next, the hand 20 is moved by driving the Y-axis drive unit 23 of the wafer transfer robot 9, and the position of the hand 20 is set to the position of the coordinate 113 on the Y-axis.

  Next, the R-axis drive unit 26 of the wafer transfer robot 9 is driven to move the hand 20 from the position of the coordinate 122 on the R-axis to the position of the coordinate 124, and is provided at the Y-shaped tip of the hand 20. The positions of the coordinates 125, 126, 127, and 128 on the R axis where the end of the reference wafer 6 overlaps the R axis are sequentially detected by the reflective sensors 31 and 37.

  At this time, the coordinate 123 on the R axis, which is the intermediate point between the coordinates 125 and 128 on the R axis, or the intermediate point between the coordinates 126 and 127 on the R axis, from the encoder value of the R axis taken into the controller 2. Is stored in the controller 2 as a detected value of the R axis.

  The distance from the coordinate 122 to the coordinate 125 on the R axis, the distance from the coordinate 122 to the coordinate 126, the distance from the coordinate 122 to the coordinate 127, and the distance from the coordinate 122 to the coordinate 128 are within the allowable range. Thus, the Y-axis movable part 23 of the wafer transfer robot 9 is driven.

  The coordinates 125, 126, 127, and 128 on the R axis are detected again, and the distance from the coordinates 122 to the coordinates 125 on the R axis, the distance from the coordinates 122 to the coordinates 126, and the coordinates 122 to the coordinates 127 are detected. It is confirmed that the distance and the distance from the coordinates 122 to the coordinates 128 are within the allowable range.

  The encoder value of the Y axis at this time is stored in the controller 2 as the detected value of the Y axis.

  The method for obtaining the coordinate 123 on the R axis is as follows. The end face of the reference wafer 6 (coordinate 120 on the R axis) is measured by the transmission sensor 33 provided at the tip of the hand 20 as in the embodiment shown in FIG. May be obtained in consideration of the size of the radius of the wafer 6 from that position.

  Next, in step 106 for determining whether or not to perform the second and subsequent detections, the procedure from the reference wafer Z-axis detection step 104 to the reference wafer R-axis and Y-axis detection step 105 is repeated two or more times. For each axis, the root mean square is obtained from the entire difference between the initial parameter and the detected value at each time.

  In step 107 of reference parameter registration, the error of the detected value of each axis is evaluated by the calculated root mean square, and the value corrected based on this evaluation is stored in the controller 2 as each axis reference parameter. .

  Then, the procedure from step 104 for detecting the reference wafer Z-axis to step 105 for detecting the R-axis and Y-axis of the reference wafer is performed once again, and the coincidence between the detected value and the reference parameter is confirmed. The reference parameters are registered in the controller 2 in the previous period.

  The procedure from step 104 for detecting the Z axis of the reference wafer to step 106 for determining whether to perform the second and subsequent detections is programmed in advance in the controller 2 and automatically operated.

  The pre-aligner 11 that stores or places the wafer 6, the supply position 10 to the semiconductor manufacturing apparatus 1, the discharge position 8, and the like can be taught in the same manner.

  Therefore, according to the wafer transfer apparatus of the above-described embodiment of the present invention, since the position is taught to the wafer transfer robot using the wafer to be actually transferred, it is not necessary to prepare a teaching jig, and the position teaching accuracy is improved. Can be improved.

  Further, since the straightness of the hand in the θ-axis direction can be obtained by the relative position with respect to the reference slit taught in advance, the teaching of the θ-axis can be omitted.

  Next, a method for confirming the gripping position of the wafer in the wafer transfer apparatus will be described below.

  A method for confirming the wafer gripping position in the wafer transfer apparatus shown in FIG. 13 will be described according to the procedure shown in the flowchart.

  In FIG. 13, in the wafer detection step 201 which is performed first when the wafer gripping is started, the wafer which moves in the transport chamber inside the mini-en housing 3 when the wafer transport device grips the active wafer 6. Using the reflective sensors 31 and 37 installed at the Y-shaped tip of the hand 20 provided in the wafer handling mechanism 15 of the transfer robot 9, the coordinates on the R-axis are the same as the method shown in FIG. The positions of 125, 126, 127, and 128 are detected.

  When the wafer 6 is held at the center by teaching the position of the wafer 6 before system operation, the positions of the four coordinates described above are detected at predetermined points.

  Next, in step 202 for determining whether the gripping position is within the allowable range, the notch portion of the wafer 6 may be detected. Therefore, out of the four points on the R axis, the coordinates of three or more points may be detected. If the position is detected within the permissible range, the process proceeds to OK display step 207 to display OK on the monitor or the upper apparatus such as the control panel in response to a command from the controller 2, and then proceeds to transfer step 208. Then, the wafer 6 is held by the hand 20, and the wafer transfer robot 9 is moved while the wafer 6 is held to transfer the wafer 6, and the next wafer 6 is smoothly held and transferred by the same procedure. .

  In step 202 for determining whether the gripping position is within the allowable range, if it is detected that the gripping position of the wafer 6 is out of the allowable range, the process proceeds to step 203 for determining whether to perform the automatic correction function.

  If it is determined in step 203 that determines whether or not this automatic correction function is to be performed, the process proceeds to step 204 where it is determined that the correction range is correct.

  If it is determined in step 204 that the correction range is within the automatic correction range, the process proceeds to correction step 209 to automatically correct the gripping position where the hand 6 of the wafer transfer robot 9 grips the wafer 6. To do.

  Then, the process returns to the wafer detection step 201 again to detect the R-axis coordinates 125, 126, 127, 128 of the wafer 6 again, and then proceeds to step 202 for determining whether the gripping position is within the allowable range, and the gripping is performed. After confirming that the position is within the allowable range, the wafer 6 is held and transported.

  Further, in the case where automatic correction is not performed in step 203 for determining whether or not the automatic correction function is to be performed, or in the case where it is detected as an automatic correction impossible range in step 204 for determining whether the correction is possible, in both cases, a warning display step 205 is performed. In step S206, a warning is displayed. Further, the flow advances to step 206 for stopping the system, and the operation of the transfer device is stopped.

  Further, the shape of the hand 20 provided in the wafer handling mechanism 15 of the wafer transfer robot 9 varies depending on the handling mechanism, but the tip of the hand 20 is extended to the back of the wafer 6 as in the backside suction type. If there is no need, the coordinates 127 and 128 on the R axis are not detected when the wafer 6 is transported, and only the coordinates 125 and 126 on the R axis need only be detected.

  In such a case, if it is determined in step 202 that the gripping position is within the allowable range, one or more of the coordinates 125 and 126 on the R axis can be detected within the allowable range. In step 207 of the display, OK is displayed, and the process proceeds to transfer step 208 where the wafer 6 is attracted to the hand 20 and transferred.

  Further, when the gripping position is detected outside the allowable range in step 202 for determining whether the gripping position is within the allowable range, it is handled in the same manner as described above.

  Further, in the case of the wafer handling mechanism 15 having the back surface suction type hand 20, the center point suction margin is larger than the center grip margin in the case of the gripping mechanism, and does not require as much accuracy as the gripping mechanism. Detection is sufficient.

  As a simple means, the reflection type sensor installed on the hand 20 is mounted with only one of the reflection type sensors 31 and 37, detects one point of the coordinates 125 or 126 on the R axis, and is allowed in consideration of the notch of the wafer 6. You may carry out similarly to said method, after expanding the range to some extent.

  The reflection type sensors 31 and 37 installed on the hand 20 can be used to check the presence of the wafer 6 on the hand 20 in order to detect the wafer 6.

  Therefore, according to the wafer transfer apparatus of the embodiment of the present invention described above, the four coordinates (coordinates 125, 126, 127, 128) on the R axis of the reference wafer 6 are obtained by the reflective sensors 31, 37 installed on the hand 20. Therefore, when the wafer 6 is gripped by the hand 20, it can be securely gripped at the center of the wafer 6 and transported.

  Further, by checking the holding position of the wafer 6 every time when the wafer 6 is held, it is possible to detect the storage state of all the wafers.

  In addition, since the alignment state of the wafer 6 can be notified to the host device and the operator by an OK display or a warning display, the wafer stored in an abnormal state can be forcibly grasped or pulled out and damaged. The risk of endangering can be avoided.

  Even when the position for gripping the wafer 6 is outside the allowable gripping range, the position of the hand for gripping the wafer 6 is automatically moved to the normal transport range by setting the automatic correction possible range and the automatic correction impossible range. Therefore, the wafer can be safely transferred.

  Further, since the wafer is detected every time when the wafer 6 is gripped, it can also be used to confirm the presence or absence of the wafer on the hand.

  The present invention is applicable to a wafer transfer apparatus that transfers a semiconductor wafer.

1 is a perspective view illustrating a schematic configuration of a wafer conveyance device according to an embodiment of the present invention. The perspective view which shows schematic structure of the wafer transfer robot 11 in the wafer transfer apparatus of the Example shown in FIG. Schematic which shows the hand holding the wafer installed in the wafer conveyance robot of the Example shown in FIG. The perspective view which shows the outline of the reference | standard slit installed in the miniene housing | casing of the wafer conveyance apparatus of the Example shown in FIG. Schematic which shows the condition which attached the reference | standard slit of the Example shown in FIG. 4 to the miniene housing | casing. The flowchart which shows the diagnostic function of the conveyance precision of the wafer conveyance apparatus of the Example shown in FIG. Schematic which shows the method of detecting with the detector installed in the hand the coordinate position of the Z-axis of the reference | standard slit of the Example shown in FIG. Schematic which shows the method of detecting with the detector installed in the hand the R-axis coordinate position of the reference | standard slit of the Example shown in FIG. Schematic which shows the method of detecting with the detector which installed the coordinate position of the Y-axis of the reference | standard slit of the Example shown in FIG. 4, and (theta) axis in the hand. The flowchart which shows the method of teaching the position of the wafer of the conveyance object by the wafer conveyance apparatus of the Example shown in FIG. Schematic which shows the method of detecting the coordinate position of the Z-axis of a wafer with the detector provided in the hand with which the wafer conveyance apparatus of the Example shown in FIG. 1 was equipped. Schematic which shows the method of detecting the R-axis and Y-axis of a wafer with the detector provided in the hand with which the wafer conveyance apparatus of the Example shown in FIG. 1 was equipped. The flowchart which shows the function which confirms the holding position of the wafer of the conveyance object by the wafer conveyance apparatus of the Example shown in FIG.

Explanation of symbols

  1: Semiconductor manufacturing apparatus, 2: Controller, 3: Mini-en housing, 4: Load port, 5: Cassette, 6: Wafer, 7: Fan filter unit, 8: Wafer discharge position, 9: Wafer transfer robot, 10: Wafer Supply position, 11: Pre-aligner, 15: Wafer handling mechanism, 20: Hand, 21: Arm, 22: Z-axis drive unit, 23: Y-axis drive unit, 24: AC servo motor, 25: θ-axis drive unit, 26 : R-axis drive unit, 31: first reflection type sensor, 32, 36: detection unit, 33: transmission type sensor, 34: light projecting unit, 35: light receiving unit, 37: second reflection type sensor, 41: Reference slit, 70: coordinates on the Z axis of the hand before sensing, 71: coordinates on the Z axis of the reference slit, 72: coordinates on the Z axis of the hand after sensing, 73: reference coordinates obtained from the parameters 74: θ-axis coordinate of the reference slit obtained from the parameter, 74: R-axis coordinate detected by the sensor of the reference slit obtained from the parameter, 80: Z-axis of the reference slit obtained from the parameter Upper coordinate, 81: R-axis coordinate of the detected reference slit, 90: Distance A from the Y-axis coordinate of the reference slit obtained from the parameter to the end surface of the reference slit, 91: Y-axis of the reference slit obtained from the parameter Distance B from the coordinate to the end face of the reference slit, 92: Z-axis coordinate at which the reflective sensor can detect the reference slit, 93: R-axis coordinate for detection by the reference slit transmission type sensor obtained from the parameters Coordinates on the R axis at a distance away from 94, 94: distance from the coordinates on the Y axis of the reference slit to the end face of the reference slit obtained from the parameters 95: distance D from the Y-axis coordinate of the reference slit to the end surface of the reference slit obtained from the parameters, 96: θ-axis coordinate of the reference slit calculated from the detected distance, 110: Z-axis of the hand before sensing Coordinates: 111: coordinates on the Z axis of the detected reference wafer, 112: coordinates on the Z axis of the hand after sensing, 113: coordinates on the Y axis of the reference wafer obtained from the parameters, 114: θ of the reference wafer obtained from the parameters Axis coordinates, 115: R-axis coordinates for detection by the transmission type sensor of the reference wafer obtained from the parameters, 120: R-axis coordinates of the detected reference wafer, 121: A distance at which the reflective sensor can detect the reference wafer A certain Z-axis coordinate, 122: R-axis coordinate before the reflective sensor detects the reference wafer, 123: R-axis of the detected reference wafer Coordinate center point, 124: coordinates on the R axis after the reflective sensor detects the reference wafer, 125: coordinates on the R axis of the wafer first detected by the first reflective sensor, 126: second reflective sensor Are the coordinates on the R-axis of the wafer detected first, 127: coordinates on the R-axis of the wafer detected later by the first reflective sensor, and 128: coordinates on the R-axis of the wafer detected later by the second reflective sensor.

Claims (8)

  A wafer storing the wafer to be supplied to a semiconductor manufacturing apparatus for processing the wafer, a cassette section for storing the wafer processed and discharged by the semiconductor manufacturing apparatus, and the cassette section attached to a wall surface on one side thereof, the semiconductor A mini-en housing that attaches a manufacturing apparatus to the other wall surface opposite to the cassette unit and forms a wafer transfer chamber therein, and holds the wafer stored in the cassette unit to manufacture the cassette unit and the semiconductor A wafer handling robot equipped with a wafer handling mechanism that can move between the apparatus and move in the transfer chamber formed in the mini-en housing, and is installed in the wafer handling mechanism of the wafer handling robot to grip the wafer. And a detector for detecting a detection object provided in the hand unit. , Based on the position of the reference slit that sets the reference in a plurality of directions in the transfer chamber that is installed in the mini-en housing and moves by the wafer transfer robot, and the reference slit of the detection object detected by the detector of the hand unit A wafer transfer apparatus comprising a controller for controlling a moving direction of the wafer transfer robot.   2. The wafer transfer apparatus according to claim 1, wherein the position of the reference slit detected by the detector for detecting the detection object provided in the hand unit is the vertical Z-axis and the hand in which the reference slit is installed. Each of the reference slits detected by the detector. The R-axis in the expansion / contraction direction of the transfer robot, the Y-axis in the traveling direction of the transport robot, and the θ-axis along the rotation direction of the hand. Based on the respective positions with respect to the axis, the Z-axis in the vertical direction, which is the moving direction of the wafer transfer robot, the R-axis in the hand expansion / contraction direction, the Y-axis in the travel direction of the transfer robot, and the θ-axis along the rotation direction of the hand A wafer transfer apparatus that controls movement in each axial direction.   3. The wafer conveyance device according to claim 2, wherein the detector provided in the hand unit includes a transmission type sensor that detects positions of the reference slit with respect to the Z axis and the R axis, and the θ axis of the reference slit. A wafer transfer apparatus comprising: a reflective sensor for detecting each position with respect to the Y axis.   2. The wafer conveyance device according to claim 1, wherein the reference slit is configured such that an attachment position thereof can be adjusted.     3. The wafer transfer apparatus according to claim 2, wherein the control controller is configured to detect the reference slit based on detection positions of the reference slit with respect to the Z, R, Y, and θ axes. The positional relationship of the Z-axis, R-axis, Y-axis, and θ-axis directions of the wafer transfer robot is obtained by calculation, and the Z-axis, R-axis, Y-axis, and θ-axis directions obtained by this calculation are calculated. A wafer transfer apparatus for controlling movement of each wafer transfer robot in each axial direction based on a positional relationship.   2. The wafer transfer apparatus according to claim 1, wherein an outer surface of the reference slit is covered with an elastic material.   A wafer storing the wafer to be supplied to a semiconductor manufacturing apparatus for processing the wafer, a cassette section for storing the wafer processed and discharged by the semiconductor manufacturing apparatus, and the cassette section attached to a wall surface on one side thereof, the semiconductor A mini-en housing that attaches a manufacturing apparatus to the other wall surface opposite to the cassette unit and forms a wafer transfer chamber therein, and holds the wafer stored in the cassette unit to manufacture the cassette unit and the semiconductor A wafer handling robot equipped with a wafer handling mechanism that can move between the apparatus and move in the transfer chamber formed in the mini-en housing, and is installed in the wafer handling mechanism of the wafer handling robot to grip the wafer. And a detector for detecting a detection object provided in the hand unit. And a controller for controlling the movement direction of the wafer transfer robot based on the wafer of the detection object stored in the cassette unit and the position of the wafer detected by the detector provided in the hand unit. A wafer transfer device characterized by the above.   8. The wafer transfer apparatus according to claim 7, wherein the position of the wafer detected by a detector that detects a detection object provided in the hand unit is a vertical Z axis on which the wafer is installed, The position of each of the R axis in the expansion / contraction direction, the Y axis in the traveling direction of the transfer robot, and the θ axis along the rotation direction of the hand, and the control controller for each axis of the wafer detected by the detector Based on the respective positions, each of the Z-axis in the vertical direction, which is the moving direction of the wafer transfer robot, the R-axis in the extension / contraction direction of the hand, the Y-axis in the travel direction of the transfer robot, and the θ-axis along the rotation direction of the hand A wafer transfer apparatus for controlling movement in an axial direction.

Images