Processing device

Abstract

To provide a processing device that can prevent damage to a wafer.SOLUTION: A grinding device (1) includes a second cassette stage (16) for mounting a second cassette (18) having a plurality of shelves (182) for storing wafers (W), a grinding mechanism (60) for processing wafers, and a robot (19) for transferring wafers to and from the second cassette. The robot includes a robot hand (21) for holding a wafer, a sensor (27) for detecting the wafer held by the robot hand, a horizontal movement mechanism (23) for moving the robot hand in a horizontal direction, and a vertical movement mechanism (24) for moving the robot hand in a vertical direction. A determination part (73) is further included for determining whether a wafer has been ejected from the cassette on the basis of the detection results of a sensor at a horizontal position of the robot hand set in advance.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a processing apparatus including a robot that transports wafers to a cassette. [Background technology]

[0002] Patent Documents 1 and 2 disclose grinding devices that grind wafers. In Patent Documents 1 and 2, the ground wafer is held on a spinner table and cleaned, and then the wafer is held by a robot hand and transported from the spinner table to a cassette for storage. At this time, the robot hand holding the wafer is advanced into the cassette, the wafer is separated from the robot hand, and the robot hand is then withdrawn from the cassette. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2018-207032 A [Patent Document 2] Patent Publication No. 2021-132181 Summary of the Invention [Problem to be solved by the invention]

[0004] In Patent Documents 1 and 2, when the robot hand is removed from the cassette, the robot hand may take out a wafer that has been attracted to the robot hand by static electricity or the like. In this case, the wafer may fall out of the cassette or the robot may come into contact with the wafer protruding from the cassette, damaging the wafer.

[0005] The present invention has been made in view of the above-mentioned points, and one of its objects is to provide a processing apparatus that can prevent damage to wafers when a robot hand is withdrawn from a cassette. [Means for solving the problem]

[0006] One embodiment of the processing apparatus of the present invention is a processing apparatus comprising a cassette stage on which a cassette having a plurality of shelves for storing wafers is placed, a chuck table for holding the wafers, a processing unit for processing the wafers, and a robot for transporting wafers into and out of the cassette placed on the cassette stage, the robot comprising a robot hand for holding the wafer, a sensor for detecting the wafer held by the robot hand, a horizontal movement mechanism for moving the robot hand in a horizontal direction, and a vertical movement mechanism for moving the robot hand in a vertical direction, and further comprising a judgment unit for determining whether a wafer has protruded from the cassette based on the detection result of the sensor at a preset horizontal position of the robot hand. Effect of the Invention

[0007] According to the present invention, when the robot hand is withdrawn from the cassette, the judgment unit can judge whether the wafer has jumped out of the cassette based on the detection result of the sensor. This makes it possible to notify the operator of the jump, and prevents the wafer from falling out of the cassette or being damaged due to contact between the robot and the wafer that has jumped out of the cassette. [Brief description of the drawings]

[0008] [Figure 1] 1 is a perspective view of a grinding device according to an embodiment; [Diagram 2] FIG. 2 is a schematic diagram of a robot, a second cassette, and their surrounding structures. [Diagram 3] FIG. 2 is a plan view of the robot hand and the wafer. [Figure 4] FIG. 13 is an explanatory diagram of a midway stage in which the robot hand is withdrawing from the second cassette. [Diagram 5] FIG. 13 is an explanatory diagram showing a state in which the wafers are protruding from the second cassette. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, a case where a processing device according to an embodiment is applied to a grinding device will be described with reference to the attached drawings. Note that the grinding device according to the embodiment is not limited to the configuration shown below and can be appropriately modified.

[0010] FIG. 1 is a perspective view of a grinding device according to an embodiment. First, the overall configuration of the grinding device 1 will be described with reference to FIG. 1. The X-axis, Y-axis, and Z-axis directions shown in FIG. 1 are perpendicular to each other. The X-axis and Y-axis directions are substantially horizontal, and the Z-axis direction is an up-down direction (vertical direction). In addition, in the following drawings, the front side in the X-axis direction is 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 and the lower side as the -Z side.

[0011] 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 be applied to other processing apparatuses equipped with various tables, processing mechanisms, transport mechanisms, etc. The grinding apparatus 1 is configured to perform a series of processes on a wafer W, including a carry-in process, a grinding process, a cleaning process, and a carry-out process.

[0012] The wafer W is an example of an object to be transported, and may be, for example, a substantially circular semiconductor wafer. A device (not shown) is formed on the front surface W1 of the wafer W. The front surface W1 of the wafer W faces downward in FIG. 1 and is protected by a protective tape T attached thereto. The back surface W2 of the wafer W is the surface to be ground on which the grinding process is performed. The wafer W may be any plate-shaped 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 a package substrate for a semiconductor product.

[0013] The grinding device 1 comprises a substantially rectangular first device base 11, a second device base 12 connected to the rear (-X side) of the first device base 11, a column 13 extending upward from the rear of the second device base 12, and a housing 14 covering the first device base 11 and the second device base 12.

[0014] A first cassette stage 15 and a second cassette stage 16 are provided on the front side (+X side) of the first device base 11. The first cassette stage 15 and the second cassette stage 16 are arranged side by side in the Y-axis direction, with the first cassette stage 15 on the right side (-Y side) and the second cassette stage 16 on the left side (+Y side). A first cassette (not shown) that stores wafers W before grinding is placed on the first cassette stage 15. A second cassette 18 that stores wafers W after grinding is placed on the second cassette stage 16. The wafers W are carried into the grinding device 1 while being stored in the first cassette, and are stored in the second cassette 18 after being ground and cleaned.

[0015] The first cassette and the second cassette 18 are open at the rear (-X side). Here, the grinding apparatus 1 includes a robot 19 disposed on the upper surface of the first apparatus base 11 behind the first cassette stage 15 and the second cassette stage 16. The robot 19 carries out the wafers W before grinding from the first cassette and carries the wafers W after grinding into the second cassette 18.

[0016] The robot 19 includes an arm structure 20 consisting of a multi-joint link, and a robot hand 21 attached to the tip of the arm structure 20 and holding a wafer W. In this embodiment, the robot hand 21 is formed in a circular flat plate shape, and at least one surface in the thickness direction is made into a holding surface 210 for holding the wafer W by suction.

[0017] The grinding apparatus 1 further includes a temporary placement table 30 and a spin cleaning mechanism 31 provided behind the robot 19.

[0018] The temporary placement table 30 is for temporarily placing the wafer W, and is provided adjacent to the rear of the robot 19, aligned in the Y-axis direction with the spin cleaning mechanism 31. A plurality of alignment pins 33 are disposed at positions surrounding the temporary placement table 30. The alignment pins 33 move in the radial direction of the temporary placement table 30, thereby aligning (centering) the center of the wafer W placed on the temporary placement table 30 so that it coincides with the center of the temporary placement table 30.

[0019] The spin cleaning mechanism 31 includes a spinner table 35 and a nozzle (not shown) that sprays cleaning water and dry air toward the spinner table 35. In the spin cleaning mechanism 31, cleaning water is sprayed from the nozzle onto the wafer W held on the spinner table 35 to clean the wafer W, and after cleaning, dry air is blown onto the wafer W from the nozzle to dry the wafer W. The left side and upper side of the spinner table 35 are covered with a cover 37.

[0020] The grinding apparatus 1 further includes a first transport mechanism 41 and a second transport 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 suction-holds the wafer W. The first transport mechanism 41 transports the wafer W from the temporary placement table 30 to the chuck table 43 before grinding. The second transport mechanism 42 transports the wafer W after grinding from the chuck table 43 to the spin cleaning mechanism 31. A transport pad 45 that suction-holds the wafer W is attached to the first transport mechanism 41 and the second transport mechanism 42.

[0021] 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 is movable in the X-axis direction together with the chuck table 43, and a bellows-shaped waterproof cover 48. A table moving mechanism (not shown) that moves the chuck table 43 in the X-axis direction is provided below the waterproof cover 48. The table moving mechanism includes a ball screw that extends in the X-axis direction, and when the ball screw is rotated, the moving plate 47 advances and retreats in the X-axis direction.

[0022] The chuck table 43 is connected to a table rotating means (not shown) and can be rotated about an axis facing the Z-axis direction by driving the table rotating means. The chuck table 43 has a holding surface 431 made of a porous ceramic material, and the wafer W is sucked and held by negative pressure generated on the holding surface 431.

[0023] The grinding device 1 includes a lifting mechanism 50 provided on the column 13, and a grinding mechanism (processing unit) 60 that is moved 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 toward and away from the chuck table 43, and the wafer W can be ground by the grinding mechanism 60.

[0024] The lifting mechanism 50 includes a pair of parallel guide rails 51 disposed on the front side of the column 13 and extending in the Z-axis direction, and a lifting table 52 installed so as to be slidable in the Z-axis direction relative to the pair of guide rails 51. The lifting mechanism 50 further includes a ball screw 53 extending in the Z-axis direction and screwed into a screwing portion (not shown) of the lifting table 52, and the ball screw 53 is rotated by the driving force of a motor 54 connected to one end of the ball screw 53, whereby the lifting table 52 moves in the Z-axis direction.

[0025] The grinding mechanism 60 is attached to the front surface of the lift table 52 via a housing 61, and is configured to rotate a grinding wheel 63 with a spindle unit 62. The spindle unit 62 is, for example, an air spindle, and rotatably supports a spindle shaft 64 inside the casing via high-pressure air. The spindle shaft 64 is a shaft body that extends in the Z-axis direction.

[0026] A mount 65 is connected to the tip (lower end) of the spindle shaft 64, and a grinding wheel 63 is attached to the mount 65. A plurality of grinding stones 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 stones 66.

[0027] The grinding apparatus 1 is provided with a control unit 70 that controls each unit of the apparatus. The control unit 70 is composed of a processor, memory, etc. that execute various processes. For example, the control unit 70 controls the grinding mechanism 60, the lifting mechanism 50, etc. according to a control program stored in the memory, and grinds the wafer W until the thickness of the wafer W reaches the finishing thickness. The control unit 70 also controls the transport operation of the wafer W by the robot 19 and the transport mechanisms 41 and 42, the cleaning operation of the wafer W by the spin cleaning mechanism 31, etc.

[0028] Regarding the operation of each part of the grinding device 1 described below, unless a control entity is specified, it is assumed that the operation is controlled by a control signal sent from the control unit 70.

[0029] Fig. 2 is a schematic diagram of the robot, the second cassette, and their peripheral structure. As shown in Fig. 2, the second cassette 18 placed on the second cassette stage 16 has an opening 181 formed at the rear (-X side). In addition, in the state shown in Fig. 2, an insertion / removal opening 141 is formed and opened in an area of ​​the housing 14 facing the opening 181 of the second cassette 18. The insertion / removal opening 141 of the housing 14 and the opening 181 of the second cassette 18 are passed by the wafer W held by the robot hand 21, and the wafer W is carried in and out of the grinding device 1.

[0030] The second cassette 18 has therein a plurality of shelves 182 for storing the wafers W. The shelves 182 are provided so as to protrude inward by a predetermined amount from the inner surface of the side wall on both sides in the Y-axis direction of the second cassette 18, and partially support both sides in the Y-axis direction of the stored wafers W. Thus, the wafers W supported by the shelves 182 are exposed except for partial regions on both sides in the Y-axis direction of the surface facing downward, and can be contacted by the holding surface 210 of the robot hand 21.

[0031] Although not shown in the drawings, the first cassette and its peripheral structure are configured similarly to the above-mentioned second cassette 18 and its peripheral structure.

[0032] The arm structure 20 of the robot 19 includes a top-bottom inversion mechanism 22 , a horizontal movement mechanism 23 , a vertical movement mechanism 24 , and a position output unit 25 .

[0033] The up-down inversion mechanism 22 rotates the robot hand 21 around an axis parallel to the X-axis direction in Fig. 2. The up-down inversion mechanism 22 starts and stops the rotation every 180°, thereby inverting the up-down orientation of the wafer W held by the robot hand 21.

[0034] The horizontal movement mechanism 23 moves the up-down inversion mechanism 22 and the robot hand 21 in a horizontal direction parallel to the XY plane. In addition, the horizontal movement mechanism 23 rotates the up-down inversion mechanism 22 and the robot hand 21 around an axis parallel to the Z-axis direction.

[0035] The vertical movement mechanism 24 moves the horizontal movement mechanism 23, the up-down inversion mechanism 22, and the robot hand 21 in the vertical direction (Z-axis direction).

[0036] The position output unit 25 is composed of an encoder or the like that detects the mechanical movement amount and rotation angle of the up-down inversion mechanism 22, the horizontal movement mechanism 23, and the vertical movement mechanism 24. The position output unit 25 detects the position of the robot hand 21 in each of the X, Y, and Z axial directions and the up-down orientation of the holding surface 210, and outputs the detection results to the control unit 70 as an electrical signal.

[0037] The robot 19 also includes a sensor 27 (see FIG. 2) that detects the wafer W held by the robot hand 21. The sensor 27 is, for example, a reflective photoelectric sensor, and includes a light-projecting unit 271 that projects measurement light onto the wafer W housed in each cassette 18, and a light-receiving unit 272 that receives the light reflected by the wafer W. When the holding surface 210 of the robot hand 21 holds the wafer W, or when the wafer W approaches within a predetermined distance from the holding surface 210, the sensor 27 detects the wafer W by receiving the reflected light with the light-receiving unit 272, and outputs the detection result as an electric signal to the control unit 70. The sensor 27 is provided at a position closer to the base B than the center position of the circular area of ​​the robot hand 21 (see FIG. 3).

[0038] The sensor 27 outputs an OFF signal when the detection light projected from the light projecting unit 271 is not received by the light receiving unit 272, and outputs an ON signal when the detection light is received by the light receiving unit 272. In this specification, the state in which the sensor 27 outputs an ON signal is referred to as the "ON state", and the state in which the sensor 27 outputs an OFF signal is referred to as the "OFF state". Thus, when the wafer W is held by the robot hand 21 and the detection light is reflected by the wafer W and the light receiving unit 272 receives the detection light, the "ON state" is reached, making it possible to detect the state in which the wafer W is held by the robot hand 21.

[0039] In the grinding apparatus 1 configured as above, the wafer W accommodated in the first cassette (not shown) is held by the robot hand 21, and the wafer W is transported to the temporary placement table 30 by driving the robot 19. The wafer W placed on the temporary placement table 30 has the back surface W2 facing upward. Next, the wafer W is transported from the temporary placement table 30 to the chuck table 43 by the first transport mechanism 41 and held by suction.

[0040] The chuck table 43 holding the wafer W by suction is moved backward by the table moving mechanism and positioned at a processing position below the grinding mechanism 60. Next, 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 the back surface W2 side of the wafer W is ground while being pressed by the grinding wheel 66 rotating at high speed. 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.

[0041] After the grinding process, the chuck table 43 is moved forward (to the +X side) by the table moving mechanism and positioned at a transfer position near the second transfer mechanism 42. Next, the wafer W is transferred from the chuck table 43 to 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 wafer W is cleaned, the wafer W on the spinner table 35 is held by the robot hand 21, and the wafer W is transported and stored in the second cassette 18 by driving the arm structure 20.

[0042] Here, the transportation of the wafer W into the second cassette 18 will be further described below with reference to FIG. 2, as well as FIG. 4 and FIG. 5. FIG. 4 is an explanatory diagram of an intermediate stage in which the robot hand is withdrawn from the second cassette. FIG. 5 is an explanatory diagram of a state in which the wafer has been ejected from the second cassette. As shown in FIG. 2, the holding surface 210 of the robot hand 21 faces downward and holds the upper surface (rear surface W2) of the wafer W by suction. In this state, the horizontal movement mechanism 23 and the vertical movement mechanism 24 of the robot 19 are driven, and the robot hand 21 holding the wafer W enters the second cassette 18 and places the wafer W on the shelf 182. After the wafer W is placed, the suction holding of the wafer W by the holding surface 210 of the robot hand 21 is released. Next, as shown in FIG. 4, the vertical movement mechanism 24 of the robot 19 is driven to move the robot hand 21 upward and separate the robot hand 21 from the upper surface of the wafer W.

[0043] Thereafter, from the state shown in FIG. 4, the horizontal movement mechanism 23 of the robot 19 is driven, and the robot hand 21 is moved backward (to the -X side) and withdrawn from the second cassette 18.

[0044] At this time, the wafer W may be attracted to the robot hand 21 by static electricity or the like, and the wafer W may unintentionally pop out from the opening 181 of the second cassette 18.

[0045] In order to recognize such a state, this embodiment has a function of detecting the wafer W protruding from the opening 181. To perform this function, the control unit 70 is configured with the functional blocks shown in FIG. 2. The control unit 70 has, as its functional blocks, a memory unit 71, a horizontal position recognition unit 72, and a judgment unit 73. These functional blocks are realized by executing a program stored in the memory unit 71. Note that the functional blocks of the control unit 70 shown in FIG. 2 show only the configuration related to the present invention, and other configurations are omitted.

[0046] The storage unit 71 stores a preset position in the X-axis direction (horizontal direction) of the robot hand 21. As an example of such a position, as shown in Fig. 5, a position where the end of the wafer W on the -X side protrudes outward (to the -X side) by a predetermined width from the opening 181 (hereinafter referred to as "determination position").

[0047] The horizontal position recognition unit 72 recognizes the position of the sensor 27 in the robot hand 21 in the horizontal direction (X-axis direction) based on the detection result output from the position output unit 25 of the robot 19.

[0048] The determination unit 73 acquires the position in the X-axis direction (horizontal direction) of the sensor 27 in the robot hand 21 recognized by the horizontal position recognition unit 72. Furthermore, when the acquired position of the sensor 27 reaches the judgment position stored in the memory unit 71, the determination unit 73 judges whether or not the wafer W protrudes from the second cassette 18 based on the detection result of the ON signal or OFF signal output from the sensor 27.

[0049] The determination unit 73 may also obtain the recognition result of the horizontal position recognition unit 72 at the time when an OFF signal is output as the detection result of the sensor 27. In this case, the determination unit 73 compares the horizontal position of the robot hand 21, which is the recognition result of the horizontal position recognition unit 72, with the determination position stored in the memory unit 71, and determines whether or not the wafer W protrudes from the second cassette 18.

[0050] In this embodiment, after the wafer W is transferred into the second cassette 18, when the robot hand 21 exits the second cassette 18, a recognition step is performed to recognize whether the wafer W has protruded.

[0051] In this recognition process, the robot hand 21 is moved backward (to the -X side) by the horizontal movement mechanism 23 from the state shown in Fig. 4. Then, at the point in time when the position of the sensor 27 in the robot hand 21 in the X-axis direction (horizontal direction) reaches the judgment position stored in the storage unit 71, the horizontal position recognition unit 72 outputs the detection result from the sensor 27 to the judgment unit 73.

[0052] 5, when the wafer W protrudes from the opening 181, the holding surface 210 and the upper surface of the wafer W are separated by a predetermined distance in the vertical direction but are kept close to each other, so that an ON signal is output as a detection result from the sensor 27. Based on the detection result of the sensor 27, the determination unit 73 determines that the wafer W protrudes from the second cassette 18.

[0053] Furthermore, even if the upper surface of the wafer W is attracted to and in contact with the holding surface 210 of the robot hand 21, an ON signal is output from the sensor 27, and the judgment unit 73 determines that the wafer W has protruded from the second cassette 18.

[0054] On the other hand, when the wafers W are stored without protruding from the opening 181, no wafers W are present below the sensor 27, and an OFF signal is output as a detection result from the sensor 27. Based on the detection result of the sensor 27, the determination unit 73 determines that the wafers W are not protruding from the second cassette 18.

[0055] 4, the sensor 27 may continuously or intermittently detect the wafer W. In this case, when the signal output from the sensor 27 switches from an ON signal to an OFF signal, the determination unit 73 compares the X-axis direction position of the sensor 27 recognized by the horizontal position recognition unit 72 with the determination position stored in the memory unit 71. Then, the determination unit 73 determines that the wafer W protrudes from the second cassette 18 if the X-axis direction position of the sensor 27 recognized by the horizontal position recognition unit 72 is on the -X side of the determination position, and determines that the wafer W does not protrude from the second cassette 18 if the X-axis direction position of the sensor 27 recognized by the horizontal position recognition unit 72 is on the +X side of the determination position.

[0056] By carrying out the recognition process as described above, it is possible to determine whether or not the wafer W is protruding from the opening 181 of the second cassette 18. As a result, if the wafer W is protruding, an alarm is generated to notify the operator, and the operator is prompted to perform the task of placing the wafer W in the second cassette 18, thereby ensuring the task. As a result, it is possible to prevent the wafer W from falling from the second cassette 18 and to prevent a part of the robot 19 from coming into contact with the wafer W protruding from the second cassette 18, thereby preventing damage to the wafer W.

[0057] In addition, the sensor 27 also detects the holding state of the wafer W in the robot hand 21. In other words, the sensor 27 that detects the holding state of the wafer W is used in the above recognition process. Therefore, without adding a new sensor to the grinding device 1, it is possible to detect and determine whether the wafer W has protruded, and an increase in equipment costs can be suppressed.

[0058] The present invention is not limited to the above-described embodiment, and can be modified in various ways. In the above-described embodiment, the size and shape shown in the attached drawings are not limited to these, and can be modified as appropriate within the scope of the effects of the present invention. In addition, the present invention can be modified as appropriate without departing from the scope of the object of the present invention.

[0059] The robot hand 21 in the above embodiment may be modified to have a shape other than a circle, such as a U-shape, a C-shape, or a square shape, depending on the conditions of the wafer W to be transported.

[0060] In the above embodiment, the position of the sensor 27 can be changed as appropriate. The position of the sensor 27 can be shifted in the X-axis direction within the plane of the holding surface 210 of the robot hand 21, or a plurality of sensors can be provided lined up in the X-axis direction.

[0061] Further, the sensor 27 may be modified in various ways, for example, by using a capacitance sensor that detects the capacitance between the sensor 27 and the wafer W in a non-contact manner, so long as the sensor 27 can detect the wafer W.

[0062] Moreover, the wafers W in the second cassette 18 may be placed upside down. [Industrial Applicability]

[0063] As described above, the present invention has the effect of being able to determine that a wafer has jumped out of a cassette when a robot hand retracts from the cassette, etc., and to prevent the wafer from being damaged. [Explanation of symbols]

[0064] 1: Grinding equipment (processing equipment) 15: 1st Cassette Stage (Cassette Stage) 16: 2nd Cassette Stage (Cassette Stage) 17: 1st cassette (cassette) 18: 2nd cassette (cassette) 182: Shelf 19:Robot 21: Robot Hand 23: Horizontal movement mechanism 24: Vertical movement mechanism 27: Sensor 43: Chuck table 73:Judgment Department W: Wafer

Claims

[Claim 1] A processing apparatus including: a cassette stage for mounting a cassette having a plurality of shelves for storing wafers; a chuck table for holding the wafers; a processing unit for processing the wafers; and a robot for loading and unloading wafers into and from the cassette mounted on the cassette stage, the robot includes a robot hand that holds a wafer, a sensor that detects the wafer held by the robot hand, a horizontal movement mechanism that moves the robot hand in a horizontal direction, and a vertical movement mechanism that moves the robot hand in a vertical direction; The processing apparatus further comprises a determination unit which determines whether or not a wafer protrudes from the cassette based on a detection result of the sensor at a preset horizontal position of the robot hand.

Images