Transport device

Abstract

To provide a transport device capable of preventing deterioration of a productivity by a conversion of a robot hand.SOLUTION: A transport device holds a wafer (W) by a robot hand (21) mounted to a robot (20), and carries-in / out the wafer so as to pass an open part (171) of a first cassette (17). The transport device comprises: a sensor that crosses the open part of the first cassette to a vertical direction, and detects that the wafer is deviated to the open part; a horizontal direction movement mechanism (23) that moves the robot hand to a horizontal direction; a horizontal position recognition part (72) that recognizes a position of a horizontal direction of the robot hand; a storage part (71) that stores a shape of the robot hand corresponded to the position of the horizontal direction of the robot hand; and a shape recognition part (73) that refers data to be stored to a storage part by a fact that the sensor becomes an ON state, and the position of the robot hand in the horizontal direction to be recognized, and recognizes the shape of the robot hand.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a transfer device that holds and transfers a wafer by a robot hand.

Background Art

[0002] Patent Document 1 discloses a grinding device that grinds a wafer with a grinding wheel. In Patent Document 1, a cassette containing a wafer is placed on a cassette stage, and the wafer contained in the cassette is held by a robot hand of a robot and taken out of the cassette. Then, the wafer after grinding is cleaned by a spinner table, held by a robot hand, and carried into the cassette.

[0003] This robot hand may be replaced when the wafer changes. For example, when the thickness of the wafer after grinding is 50 μm, a spinner table for cleaning the wafer uses one with an area larger than the area of the wafer so as to support the entire lower surface of the wafer. Therefore, a spatula-shaped robot hand that sucks and holds the upper surface of the wafer is used.

[0004] Also, in the case of a wafer for which it is not desired to scratch the upper surface of the wafer, a spinner table with an area smaller than the area of the wafer is used to support a part of the center on the lower surface of the wafer. And a U-shaped robot hand that sucks and holds the lower surface of the wafer while avoiding the spinner table is used.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] As described above, when the type of the wafer or spinner table to be held is changed, the operator replaces the robot hand and further changes the operation settings of the robot adapted to the robot hand. Therefore, if the operator forgets the operation settings unintentionally, the transfer and processing of the wafer may stop, resulting in a problem of reduced productivity.

[0007] In view of such a point, the present invention is made, and one of the objects is to provide a transfer device capable of preventing a decrease in productivity due to the replacement of the robot hand.

Means for Solving the Problems

[0008] A transfer device according to an aspect of the present invention is a transfer device that holds a wafer by a holding surface of a robot hand attached to a robot and carries the wafer into or out of the cassette through an opening of the cassette, the transfer device including: a cassette stage on which the cassette is placed; a sensor that vertically cuts the opening of the cassette in the vertical direction and detects that the wafer has jumped out of the cassette into the opening; the robot hand attached to the robot; a horizontal movement mechanism that moves the robot hand in the horizontal direction; a horizontal position recognition unit that recognizes the horizontal position of the robot hand; a storage unit that stores the shape of the robot hand corresponding to the horizontal position of the robot hand; and a shape recognition unit that refers to the data stored in the storage unit based on the fact that the sensor is in an ON state and the position of the robot hand in the horizontal direction recognized by the horizontal position recognition unit and recognizes the shape of the robot hand.

[0009] In addition, a transfer device according to an aspect of the present invention is a transfer device that holds a wafer by a holding surface of a robot hand attached to a robot and transfers the wafer into or out of the cassette through an opening of the cassette, and includes a cassette stage on which the cassette is placed, a sensor that vertically cuts through the opening of the cassette and is arranged in a plurality in the horizontal direction to detect that the wafer has jumped out of the cassette into the opening, the robot hand attached to the robot, a horizontal movement mechanism that moves the robot hand in the horizontal direction, and a horizontal position recognition unit that recognizes the horizontal position of the robot hand. The transfer device is provided with a drawing unit that draws the shape of the robot hand based on the positions of a plurality of locations in the horizontal direction of the robot hand entering the cassette from the outside of the opening and the ON state and OFF state of each of the sensors at the plurality of locations of the robot hand.

Advantages of the Invention

[0010] According to the present invention, based on the detection result of the sensor or the like, by recognizing the shape of the robot hand in the shape recognition unit or drawing the shape of the robot hand in the drawing unit, when using a plurality of types of robot hands, it becomes easier to grasp the change or replacement of the attached robot hand. As a result, the operator can be prompted by an alarm or the like to perform the operation setting work associated with the change of the robot hand, and the operation can be surely performed. As a result, damage to the robot hand or the like can be prevented in advance, and the transfer and processing of the wafer can be avoided from stopping, and the productivity can be kept good.

Brief Description of the Drawings

[0011]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Embodiments for Carrying Out the Invention

[0012] Hereinafter, with reference to the accompanying drawings, a grinding apparatus including a transfer device according to each embodiment will be described. Note that the grinding apparatus according to each embodiment is not limited to the configuration shown below, and can be appropriately changed.

[0013] [First Embodiment] FIG. 1 is a perspective view of a grinding apparatus according to the first embodiment. First, with reference to FIG. 1, the overall configuration of the grinding apparatus 1 will be described. The X-axis direction, Y-axis direction, and Z-axis direction shown in FIG. 1 are perpendicular to each other. The X-axis direction and Y-axis direction are substantially horizontal directions, and the Z-axis direction is the vertical direction (up and down direction). Also, in the following figures, the front side in the X-axis direction may be referred to as the +X side, the rear side as the -X side, the left side in the Y-axis direction as the +Y side, the right side as the -Y side, and the upper side in the Z-axis direction as the +Z side, the lower side as the -Z side.

[0014] The grinding apparatus 1 shown in FIG. 1 is an example of a processing apparatus to which the present invention is applied. Note that the present invention is not limited to the grinding apparatus 1, and can also be applied to other processing apparatuses including various tables, processing mechanisms, transfer mechanisms, etc. The grinding apparatus 1 is configured to perform a series of processes including a loading process, a grinding process, a cleaning process, and an unloading process on the wafer W.

[0015] The wafer W is an example of an object to be transported, and is, for example, a substantially circular semiconductor wafer. Devices (not shown) are formed on the surface W1 of the wafer W. The surface W1 of the wafer W faces downward in FIG. 1 and is protected by attaching a protective tape T thereto. The back surface W2 of the wafer W is a surface to be ground. Note that the wafer W may be any plate-like workpiece to be ground, and may be a semiconductor substrate such as silicon or gallium arsenide, an inorganic material substrate such as ceramic, glass, or sapphire, or even a package substrate of a semiconductor product.

[0016] The grinding apparatus 1 includes a substantially rectangular first apparatus base 11, a second apparatus base 12 connected to the rear (-X side) of the first apparatus base 11, a column 13 extending upward from the rear part of the second apparatus base 12, and a housing 14 covering the first apparatus base 11 and the second apparatus base 12.

[0017] A first cassette stage 15 and a second cassette stage 16 are provided on the front side (+X side) of the first apparatus base 11. The first cassette stage 15 and the second cassette stage 16 are provided side by side in the Y-axis direction, with the first cassette stage 15 disposed on the right side (-Y side) and the second cassette stage 16 disposed on the left side (+Y side). A first cassette 17 (not shown in FIG. 1, see FIG. 2) in which the wafer W before grinding is accommodated is placed on the first cassette stage 15. A second cassette 18 in which the wafer W after grinding is accommodated is placed on the second cassette stage 16. The wafer W is carried into the grinding apparatus 1 while being accommodated in the first cassette 17, subjected to grinding and cleaning, and then accommodated in the second cassette 18.

[0018] The first cassette 17 and the second cassette 18 are open at the rear (-X side). Here, the grinding apparatus 1 includes a robot 20 disposed behind the first cassette stage 15 and the second cassette stage 16 and on the upper surface of the first apparatus base 11. By the robot 20, the wafer W before grinding is carried out from the first cassette 17, and the wafer W after grinding is carried into the second cassette 18.

[0019] The robot 20 has an arm structure composed of multiple articulated links, and a robot hand 21 for holding the wafer W is attached to the tip of the robot 20. The robot hand 21 is provided with a holding surface 210 for adsorbing and holding the wafer W. The robot 20 is configured to include a vertical inversion mechanism 22, a horizontal movement mechanism 23, and a vertical movement mechanism 24 (see FIG. 2) described later by multiple articulated links. Further, the robot 20 is provided with a position output unit 25 (see FIG. 2) such as an encoder that outputs the position in each axial direction of XYZ in the robot hand 21 and the vertical orientation of the holding surface 210.

[0020] The grinding device 1 further includes a temporary placement table 30 and a spin cleaning mechanism 31 provided behind the robot 20.

[0021] The temporary placement table 30 is for temporarily placing the wafer W, and is provided adjacent to the rear of the robot 20 and arranged side by side with the spin cleaning mechanism 31 in the Y-axis direction. A plurality of alignment pins 33 are arranged at positions surrounding the temporary placement table 30. By moving the alignment pins 33 along the radial direction of the temporary placement table 30, the center of the wafer W placed on the temporary placement table 30 is aligned (centered) so as to coincide with the center of the temporary placement table 30.

[0022] The spin cleaning mechanism 31 includes a spinner table 35 and a nozzle (not shown) that injects cleaning water and drying air toward the spinner table 35. In the spin cleaning mechanism 31, cleaning water is injected from the nozzle onto the wafer W held on the spinner table 35 to clean the wafer W, and after cleaning, drying air is blown from the nozzle to dry the wafer W. The spinner table 35 is covered with a cover 37 on the left side and the upper side.

[0023] The grinding device 1 further includes a first transfer mechanism 41 and a second transfer mechanism 42 provided between the temporary placement table 30 and the spin cleaning mechanism 31 in the Y-axis direction, and a chuck table 43 that sucks and holds the wafer W. The first transfer mechanism 41 transfers the wafer W before grinding from the temporary placement table 30 to the chuck table 43. The second transfer mechanism 42 transfers the wafer W after grinding from the chuck table 43 to the spin cleaning mechanism 31. The first transfer mechanism 41 and the second transfer mechanism 42 are equipped with transfer pads 45 that suck and hold the wafer W.

[0024] In the grinding device 1, a rectangular opening extending in the X-axis direction is formed on the upper surface of the first device base 11. This opening is covered by a moving plate 47 that can move in the X-axis direction together with the chuck table 43 and a bellows-shaped waterproof cover 48. Below the waterproof cover 48, a table moving mechanism (not shown) for moving the chuck table 43 in the X-axis direction is provided. The table moving mechanism includes a ball screw extending in the X-axis direction. When the ball screw is rotated, the moving plate 47 moves forward and backward in the X-axis direction.

[0025] The chuck table 43 is connected to a table rotation means (not shown) and can rotate about an axis facing in the Z-axis direction by driving the table rotation means. The chuck table 43 has a holding surface 431 formed of a porous ceramic material, and the wafer W is sucked and held by the negative pressure generated on the holding surface 431.

[0026] The grinding device 1 includes a lifting mechanism 50 provided on the column 13 and a grinding mechanism 60 that moves in the vertical direction (Z-axis direction) by the lifting mechanism 50. By driving the lifting mechanism 50, the grinding mechanism 60 can be moved closer to and away from the chuck table 43.

[0027] The lifting mechanism 50 includes a pair of parallel guide rails 51 arranged on the front side of the column 13 and extending in the Z-axis direction, and a lifting table 52 slidably installed in the Z-axis direction with respect to the pair of guide rails 51. Further, the lifting mechanism 50 further includes a ball screw 53 extending in the Z-axis direction and screwing into a screwing portion (not shown) of the lifting table 52. When the ball screw 53 is rotated by the driving force of a motor 54 connected to one end of the ball screw 53, the lifting table 52 moves in the Z-axis direction.

[0028] The grinding mechanism 60 is attached to the front surface of the lifting table 52 via a housing 61, and is configured to rotate a grinding wheel 63 by a spindle unit 62. The spindle unit 62 is, for example, an air spindle, and rotatably supports a spindle shaft 64 via high-pressure air inside a casing. The spindle shaft 64 is a shaft body extending in the Z-axis direction.

[0029] A mount 65 is connected to the tip (lower end) of the spindle shaft 64, and the grinding wheel 63 is mounted on the mount 65. A plurality of grinding wheels 66 are provided in an annular shape on the lower surface side of the grinding wheel 63. The grinding mechanism 60 grinds the back surface W2 of the wafer W held by suction on the chuck table 43 with the grinding wheels 66.

[0030] The grinding apparatus 1 is provided with a control unit 70 for overall control of each part of the apparatus. The control unit 70 is composed of a processor, a memory, etc. that execute various processes. The control unit 70 controls, for example, the grinding mechanism 60, the lifting mechanism 50, etc. according to a control program stored in the memory, and causes grinding to be performed until the thickness of the wafer W reaches the finished thickness. Further, the control unit 70 controls the transfer operation of the wafer W by the robot 20 and each transfer mechanism 41, 42, the cleaning operation of the wafer W by the spin cleaning mechanism 31, etc.

[0031] Regarding the operations of each part of the grinding apparatus 1 described below, when the control subject is not specified, it is assumed that the operations are controlled by a control signal sent from the control unit 70.

[0032] Figure 2 is a schematic configuration diagram of a robot, a first cassette, and its peripheral structure. As shown in Figure 2, the first cassette 17 placed on the first cassette stage 15 has an opening 171 formed at the rear (-X side). Also, in the state shown in Figure 2, an access port 141 is formed by opening in the region of the housing 14 that faces the opening 171 of the first cassette 17. The access port 141 of the housing 14 and the opening 171 of the first cassette 17 allow the wafer W held by the robot hand 21 to pass through, and the wafer W is carried into and out of the grinding device 1.

[0033] The first cassette 17 includes a plurality of shelves 172 inside. The shelves 172 are provided so as to protrude inward by a predetermined amount from the inner surfaces of the side walls on both sides in the Y-axis direction of the cassette 17, and partially support both sides in the Y-axis direction of the wafer W to be accommodated. Therefore, the wafer W supported by the shelves 172 is exposed except for a partial region on both sides in the Y-axis direction of the surface facing downward, and the holding surface 210 of the robot hand 21 can come into contact.

[0034] The access port 141 of the housing 14 is provided with a sensor 80 for detecting that the wafer W has jumped out from the inside of the first cassette 17 to the opening 171. The sensor 80 is composed of a transmissive sensor including a light projecting unit 81 that projects detection light and a light receiving unit 82 that receives the detection light. In the present embodiment, the light projecting unit 81 and the light receiving unit 82 are provided at the upper end side and the lower end side of the access port 141, respectively, so that the detection light from the light projecting unit 81 vertically cuts through the opening 171. Also, the light projecting unit 81 and the light receiving unit 82 are provided at one position in the center in the Y-axis direction of the access port 141. Therefore, when viewed from the vertical direction, the installation positions of the light projecting unit 81 and the light receiving unit 82 are set to the position through which the approximate center of the wafer W to be carried in and out passes, and when the wafer W accommodated in the first cassette 17 jumps out, it is set to the position where the wafer W first passes through the access port 141.

[0035] When the detection light emitted from the light projecting unit 81 is received by the light receiving unit 82, the sensor 80 outputs an OFF signal, and when the light receiving unit 82 does not receive the detection light, the sensor 80 outputs an ON signal. In this specification and the claims, the state in which the sensor 80 outputs an OFF signal is referred to as the "OFF state", and the state in which the sensor 80 outputs an ON signal is referred to as the "ON state". Therefore, when the wafer W pops out from the first cassette 17 and the detection light is blocked by the wafer W so that the light receiving unit 82 does not receive the detection light, it becomes the "ON state", and the state where the wafer W has popped out can be detected.

[0036] Although the illustration and description are omitted, the second cassette 18 and its peripheral structure are configured in the same manner as the above-described first cassette 17 and its peripheral structure.

[0037] The robot 20 includes a vertical inversion mechanism 22, a horizontal movement mechanism 23, a vertical movement mechanism 24, and a position output unit 25.

[0038] The vertical inversion mechanism 22 rotationally drives the robot hand 21 around an axis parallel to the X-axis direction in FIG. 2. The vertical inversion mechanism 22 drives and stops such rotational driving every 180°, thereby inverting the up and down directions of the wafer W held by the robot hand 21.

[0039] The horizontal movement mechanism 23 moves the vertical inversion mechanism 22 and the robot hand 21 in a horizontal direction parallel to the XY plane. Further, the horizontal movement mechanism 23 rotationally drives the vertical inversion mechanism 22 and the robot hand 21 around an axis parallel to the Z-axis direction.

[0040] The vertical movement mechanism 24 moves the horizontal movement mechanism 23, the vertical inversion mechanism 22, and the robot hand 21 in the vertical direction.

[0041] The position output unit 25 is composed of an encoder or the like that detects the mechanical movement amount and rotation angle of the vertical inversion mechanism 22, the horizontal movement mechanism 23, and the vertical movement mechanism 24, and outputs the detection result as an electrical signal to the control unit 70.

[0042] In the grinding apparatus 1 configured as described above, the wafer W accommodated in the first cassette 17 is held by the robot hand 21, and the wafer W is transported to the temporary placement table 30 by the drive of the robot 20. The wafer W placed on the temporary placement table 30 has its back surface W2 facing upward. Subsequently, the wafer W is transported from the temporary placement table 30 onto the chuck table 43 by the first transfer mechanism 41 and is sucked and held.

[0043] The chuck table 43 that sucks and holds the wafer W is moved backward by the table movement mechanism and positioned at the processing position below the grinding mechanism 60. Subsequently, the grinding mechanism 60 is lowered by the lifting mechanism 50 to bring the grinding wheel 66 into contact with the back surface W2 of the wafer W, and while pressing the wafer W with the high-speed rotating grinding wheel 66, the back surface W2 side is ground. When the back surface W2 side of the wafer W is ground to a desired thickness, the grinding mechanism 60 is raised by the lifting mechanism 50 to separate the grinding wheel 66 from the wafer W on the chuck table 43, and the grinding process is completed.

[0044] After the grinding process, the chuck table 43 is moved forward (+X side) by the table movement mechanism and positioned at the delivery position near the second transfer mechanism 42. Subsequently, the wafer W is transported from the chuck table 43 onto the spinner table 35 by the second transfer mechanism 42, and the wafer W is cleaned by the spin cleaning mechanism 31. After the cleaning of the wafer W, the wafer W on the spinner table 35 is held by the robot hand 21, and the wafer W is transported and accommodated into the second cassette 18 by the drive of the robot 20.

[0045] In the grinding apparatus 1, a plurality of types of robot hands 21 can be exchanged and used by the operator according to the size and thickness of the wafer W, the possibility of contact of the robot hand 21 with the back surface W2, etc. In the present embodiment, it is selected from eight types of robot hands 21 and mounted on the robot 20. Specifically, the first to eighth robot hands 211 to 218 shown in FIGS. 3 to 10 can be exemplified.

[0046] Here, in the present embodiment, wafers W of two sizes are the objects of conveyance and grinding. The wafer W with a relatively larger diameter dimension is defined as the large wafer WL, and the wafer W with a relatively smaller diameter dimension is defined as the small wafer WS. Also, in all of the first to eighth robot hands 211 to 218, the base B held at the tip of the robot 20 (FIG. 1) is formed in a flat plate shape extending in the X-axis direction.

[0047] FIG. 3 is a plan view of the first robot hand. FIG. 5 is a plan view of the third robot hand. FIG. 7 is a plan view of the fifth robot hand. The first robot hand 211, the third robot hand 213, and the fifth robot hand 215 form a circular holding surface 210 with the rear (-X side) region connected to the base B, and are provided in a shape called a spatula shape. The diameter dimension of the holding surface 210 decreases in the order of the first robot hand 211, the third robot hand 213, and the fifth robot hand 215. The diameter dimension of the first robot hand 211 is made substantially the same as that of the large wafer WL, the diameter dimension of the third robot hand 213 is made a predetermined length smaller than that of the large wafer WL, and the diameter dimension of the fifth robot hand 215 is made slightly smaller than that of the small wafer WS.

[0048] FIG. 4 is a plan view of the second robot hand. The second robot hand 212 forms a holding surface 210 extending radially from the center of the large wafer WL to be held, with the rear region connected to the base B, and is provided in a shape called a star shape. The tips of the radially extending portions of the second robot hand 212 are arranged inside the outer edge of the first robot hand 211 and outside the outer edge of the third robot hand 213 (see FIG. 11).

[0049] FIG. 6 is a plan view of the fourth robot hand. FIG. 8 is a plan view of the sixth robot hand. FIG. 9 is a plan view of the seventh robot hand. The fourth robot hand 214 and the sixth robot hand 216 form a C-shaped holding surface 210 that opens forward, and the rear region is continuous with the base B. The seventh robot hand 217 forms a U-shaped holding surface 210 that opens forward, and the rear region is continuous with the base B. The diameter dimension of the fourth robot hand 214 is formed smaller than the diameter dimension of the third robot hand 213 and larger than the diameter dimension of the fifth robot hand 215. The diameter dimensions of the sixth robot hand 216 and the seventh robot hand 217 are substantially the same as the diameter dimension of the fifth robot hand 215. The opening width in front of the seventh robot hand 217 is formed larger than the opening width in front of the sixth robot hand 216.

[0050] FIG. 10 is a plan view of the eighth robot hand. The eighth robot hand 218 extends in the X-axis direction while maintaining the width of the base B in the Y-axis direction, and forms a holding surface 210 whose front end (the end on the +X side) is located near the center of the large wafer WL to be held.

[0051] In the present embodiment, when the robot 20 is equipped with a selection from the first to the eighth robot hands 211 to 218, it has a function of recognizing the differences between the first to the eighth robot hands 211 to 218. In order to exhibit such a function, the control unit 70 is configured with the functional blocks shown in FIG. 2. The control unit 70 includes a storage unit 71, a horizontal position recognition unit 72, and a shape recognition unit 73 as functional blocks. These functional blocks are realized by executing a program stored in the storage unit 71. Note that the functional blocks of the control unit 70 shown in FIG. 2 show only the configurations related to the present invention, and other configurations are omitted.

[0052] The storage unit 71 stores the shapes of a plurality of types of robot hands 21 (in this embodiment, the first to eighth robot hands 211 to 218). Further, the storage unit 71 stores, in association with the shapes of the plurality of types of robot hands 21, the horizontal positions recognized by the horizontal position recognition unit 72 for each robot hand 21. Therefore, the storage unit 71 stores, as shape recognition data, the shapes of the plurality of types of robot hands 21 corresponding to the horizontal positions of the robot hands 21.

[0053] Based on the detection result output from the position output unit 25 of the robot 20, the horizontal position recognition unit 72 recognizes the horizontal positions (X-axis direction and Y-axis direction) of the robot hand 21.

[0054] The shape recognition unit 73 acquires the recognition result of the horizontal position recognition unit 72 when the sensor 80 changes from the OFF state to the ON state. Further, the shape recognition unit 73 refers to the horizontal position of the robot hand 21 that is the recognition result of the horizontal position recognition unit 72 and the above-described shape recognition data stored in the storage unit 71, and recognizes the shape of the robot hand 21.

[0055] In this embodiment, before the first cassette 17 is placed on the first cassette stage 15 and the accommodated wafer W is carried out, the recognition process of the robot hand 21 is performed.

[0056] In such a recognition process, with the robot hand 21 retracted rearward (outside) from the access opening 141 of the housing 14, the robot 20 is driven to a position where the robot hand 21 does not contact the shelf 172 of the first cassette 17 or the accommodated wafer W in the Z-axis direction. Also, simultaneously with or before and after such driving, the robot 20 is driven so that the central position of the robot hand 21 coincides with the position of the sensor 80 in the Y-axis direction. At this time, as shown in FIG. 2, the front end of the robot hand 21 is located rearward from the access opening 141 and the opening 171 of the first cassette 17, the detection light projected from the light projecting unit 81 is received by the light receiving unit 82, and an OFF signal is output from the sensor 80.

[0057] Subsequently, the robot hand 21 moves from the rear to the front of the access port 141, and the robot 20 is driven to enter the first cassette 17. Then, the detection light projected from the light projecting unit 81 of the sensor 80 is blocked by the robot hand 21, and the signal output from the sensor 80 switches from an OFF signal to an ON signal. When an ON signal is output from the sensor 80, based on the detection result output from the position output unit 25 of the robot 20, the horizontal position (X-axis direction and Y-axis direction) of the robot hand 21 at the time of the output of the ON signal is recognized by the horizontal position recognition unit 72.

[0058] Also, due to the sensor 80 being in the ON state, in the shape recognition unit 73, based on the horizontal position of the robot hand 21 recognized by the horizontal position recognition unit 72, the above-described shape recognition data stored in the storage unit 71 is referred to. By referring to such shape recognition data, the shape of the robot hand 21 corresponding to the recognized horizontal position of the robot hand 21 is recognized.

[0059] Next, as an example, referring to FIG. 11, the process of recognizing the shapes of the first to eighth robot hands 211 to 218 of the present embodiment will be described. FIG. 11 is an operation explanatory diagram of the process of recognizing the shape of the robot hand. For convenience of explanation, FIG. 11 shows the first robot hand 211 to the eighth robot hand 218 superimposed in order from the back to the front of the paper surface of FIG. 11.

[0060] As shown in FIG. 11, since the first to eighth robot hands 211 to 218 have the above-described shapes, the positions of the foremost ends, which are on the frontmost side (+X side), are different. More specifically, the foremost ends of the first to third robot hands 211 to 213, the sixth robot hand 216, and the eighth robot hand 218 are located on the center C in the Y-axis direction. Since the fourth robot hand 214, the fifth robot hand 215, and the seventh robot hand 217 are U-shaped or C-shaped, the foremost ends are located at a predetermined width offset from the center C in the Y-axis direction. Therefore, when the robot hands 211 to 218 are moved parallel to the X-axis direction from the state shown in FIG. 11, the foremost ends of the fourth robot hand 214, the fifth robot hand 215, and the seventh robot hand 217 cannot be detected by the sensor 80.

[0061] Therefore, in order to enable the sensor 80 to detect the positions of the foremost ends of all of the first to eighth robot hands 211 to 218, the robot hands 211 to 218 are moved along the locus R shown in FIG. 11. In other words, in the control unit 70, movement data of the locus R is stored in advance in the storage unit 71 at the preparation stage of using the first to eighth robot hands 211 to 218, and the driving of the robot 20 is controlled based on the movement data. The locus R passes through the points (1) to (8) in FIG. 11 in this order, and the points (1) to (8) are positions near the foremost ends of the first to eighth robot hands 211 to 218.

[0062] If, for example, the first robot hand 211 is attached to the robot 20, when the point (1) in FIG. 11 reaches the horizontal position where the sensor 80 is located during movement along the locus R, the sensor 80 turns on. Due to this ON state, based on the horizontal position of the first robot hand 211 recognized by the horizontal position recognition unit 72, the shape recognition unit 73 refers to the above-described shape recognition data, and the shape of the first robot hand 211 is recognized. In other words, the shape recognition data is data that associates the horizontal position of the first robot hand 211 recognized by detecting the point (1) with the sensor 80 by the horizontal position recognition unit 72 and the shape of the first robot hand 211. In a similar manner, the shape recognition data includes data that associates the horizontal positions of the second to eighth robot hands 212 to 218 recognized by detecting the points (2) to (8) with the sensor 80 by the horizontal position recognition unit 72 and the shapes of the second to eighth robot hands 212 to 218.

[0063] Therefore, for example, when the fourth robot hand 214 is attached to the robot 20, the OFF state of the sensor 80 is maintained and the robot passes through at points (1) to (3) during movement along the locus R. After passing through point (3), the robot moves along the locus R that bends toward point (4), and when point (4) reaches the horizontal position where the sensor 80 is located, the sensor 80 turns on. Thereafter, the shape of the fourth robot hand 214 is recognized by the shape recognition unit 73 in the same manner as described above.

[0064] By performing the recognition process of the robot hand 21 in this way, the shape recognition unit 73 can recognize the shapes of the first to eighth robot hands 211 to 218. As a result, even if the grinding finish thickness and size of the wafer W are changed, and the transfer conditions and the spinner table 35 are changed, it is possible to determine by shape recognition by the shape recognition unit 73 whether or not a robot hand 21 corresponding to such a change is mounted. And when a robot hand 21 that does not correspond to the change is mounted, by generating an alarm and notifying an operator, etc., the operation setting work accompanying the change of the robot hand 21 can be promoted and the certainty of the work can be achieved. Thereby, breakage etc. of the robot hand 21 can be prevented beforehand, the stop of the transfer and processing of the wafer W can be avoided, and productivity can be kept good.

[0065] Further, the sensor 80 also detects the protrusion of the wafer W. In other words, the sensor 80 that detects the protrusion of the wafer W is used in the recognition process of the robot hand 21. Therefore, the shape recognition of the robot hand 21 can be performed without adding a new sensor to the grinding apparatus 1, and an increase in equipment cost can be suppressed.

[0066] Here, the transfer device of the present invention can be configured with a minimum configuration for transferring the wafer W in the grinding apparatus 1. The transfer device preferably includes at least each cassette stage 15, 16, each cassette 17, 18, a sensor 80, a robot 20 including a horizontal movement mechanism 23, a robot hand 21, a storage unit 71, a horizontal position recognition unit 72, and a shape recognition unit 73.

[0067] [Second Embodiment] Next, a second embodiment of the present invention will be described with reference to FIG. 12. In the following description, the same reference numerals may be used for the same or equivalent components as those in the first embodiment, and the description may be omitted or simplified.

[0068] Figures 12A and 12B are explanatory diagrams of the shape recognition of the robot hand according to the second embodiment. In the second embodiment, the number of installed sensors 80 is changed compared to the first embodiment, and the shape of the robot hand 21 is drawn. The sensors 80 of the second embodiment are arranged in a plurality along the Y-axis direction (horizontal direction) at the access opening 141 of the housing 14.

[0069] Further, in the second embodiment, a drawing unit 93 (illustrated by a two-dot chain line in FIG. 2) is included as one of the functional blocks of the control unit 70. The drawing unit 93 has a function of drawing the shape of the robot hand 21 based on the ON signals and OFF signals at a plurality of sensors 80.

[0070] In the second embodiment, the robot 20 is driven so that the robot hand 21 moves from the -X side (outer side) to the +X side of the opening 171 of the first cassette 17 and enters the first cassette 17. The movement of the robot hand 21 is parallel to the X-axis direction. While moving the robot hand 21, the robot hand 21 is detected by a plurality of sensors 80 arranged in the Y-axis direction, and the OFF state and the ON state are switched according to the shape of the robot hand 21 at the positions of the plurality of sensors 80. For example, when mounting and moving the circular robot hand 21 shown in FIG. 12A, OFF signals are output at the positions represented by the broken lines of the respective sensors 80 by virtual lines extending parallel to the X-axis direction from the respective sensors 80, and ON signals are output at the positions represented by the solid lines. Also, in the C-shaped robot hand 21 shown in FIG. 12B, OFF signals and ON signals are output in the same manner.

[0071] When the output of each sensor 80 is switched, based on the detection result output from the position output unit 25 of the robot 20, the horizontal position recognition unit 72 recognizes the position of the robot hand 21 in the X-axis direction (horizontal direction) when the output of the sensor 80 is switched. Also, in the horizontal position recognition unit 72, the recognized position in the X-axis direction is associated with the position in the Y-axis direction of each sensor 80, and the position of the robot hand 21 is recognized as the coordinate value in the XY direction that is horizontal.

[0072] In the drawing unit 93, the coordinate values of the robot hand 21 recognized by the horizontal position recognition unit 72 are sequentially plotted according to the sensors 80 at a plurality of positions, so that the shape of the robot hand 21 is drawn as indicated by the two-dot chain line in FIGS. 12A and 12B.

[0073] Thus, according to the second embodiment, by drawing the robot hand 21 in the drawing unit 93, it becomes easier to grasp the change or replacement of the mounted robot hand 21, and it is possible to avoid stopping the transfer and processing of the wafer W and maintain good productivity as in the first embodiment.

[0074] Note that the present invention is not limited to the above-described embodiments, and various modifications can be made. In the above embodiments, the sizes, shapes, etc. illustrated in the accompanying drawings are not limited thereto, and can be appropriately changed within the range in which the effects of the present invention are exhibited. In addition, various modifications can be made as long as the object of the present invention is not deviated.

[0075] For example, the plurality of types of robot hands 21 illustrated and described in each embodiment are merely examples, and depending on the conditions of the wafer W to be transferred, etc., other robot hands 21 with different shapes may be increased or the mountable robot hands 21 may be decreased.

[0076] Also, in the first embodiment, the position of the sensor 80 in the Y-axis direction may be changed or the number of installed sensors 80 may be increased. However, as described above, it is advantageous in terms of simplifying the configuration to use the sensor 80 for detecting the protrusion of the wafer W and the sensor 80 for shape recognition in common.

Industrial Applicability

[0077] As described above, the present invention has an effect of prompting an operator to perform an operation setting work associated with a change of a robot hand by an alarm or the like and enhancing the certainty of the work in a transfer device that changes and uses a plurality of types of robot hands.

Explanation of Signs

[0078] 1: Grinding device 15: First cassette stage (cassette stage) 16: Second cassette stage (cassette stage) 17: First cassette (cassette) 171: Opening 18: Second cassette (cassette) 20: Robot 21: Robot hand 210: Holding surface 211: First robot hand (robot hand) 212: Second robot hand (robot hand) 213: Third robot hand (robot hand) 214: Fourth robot hand (robot hand) 215: Fifth robot hand (robot hand) 216: Sixth robot hand (robot hand) 217: Seventh robot hand (robot hand) 218: Eighth robot hand (robot hand) 23: Horizontal movement mechanism 71: Memory unit 72: Horizontal position recognition unit 73: Shape recognition unit 80: Sensor 93: Drawing unit W: Wafer

Claims

1. A transfer device that holds a wafer by a holding surface of a robot hand attached to a robot and transfers the wafer into or out of the cassette through an opening of the cassette, comprising: a cassette stage on which the cassette is placed; a sensor that vertically cuts through the opening of the cassette and detects that a wafer has popped out of the cassette into the opening; the robot hand attached to the robot; a horizontal movement mechanism that moves the robot hand in the horizontal direction; a horizontal position recognition unit that recognizes the horizontal position of the robot hand; a storage unit that stores the shape of the robot hand corresponding to the horizontal position of the robot hand; a shape recognition unit that refers to the data stored in the storage unit based on the fact that the sensor is in the ON state and the position of the robot hand in the horizontal direction recognized by the horizontal position recognition unit, and recognizes the shape of the robot hand; A transfer device comprising the above components.

2. A transfer device that holds a wafer by a holding surface of a robot hand attached to a robot and transfers the wafer into or out of the cassette through an opening of the cassette, comprising: a cassette stage on which the cassette is placed; a sensor that vertically cuts through the opening of the cassette, is arranged in a plurality in the horizontal direction, and detects that a wafer has popped out of the cassette into the opening; the robot hand attached to the robot; a horizontal movement mechanism that moves the robot hand in the horizontal direction; a horizontal position recognition unit that recognizes the horizontal position of the robot hand; and A transfer device comprising a mapping unit that maps the shape of the robot hand based on the positions of a plurality of locations in the horizontal direction of the robot hand entering the cassette from the outside of the opening and the ON state and OFF state of each of the sensors at the plurality of locations of the robot hand.

Images