Processing equipment

Abstract

To precisely grasp an appropriate exchange period of a suction cup or a pipe by easily and surely checking leakage of air from the suction cup or a suction path of a transfer mechanism.SOLUTION: A cutting device (a processing device) 1 comprises: a transfer mechanism 70 of transferring a wafer (a processed material) W while sucking and holding it; and a diagnosis part 100. The transfer mechanism 70 comprises: a transfer pad 74 that includes at least four suction cups 75; a lifting mechanism 71 that lifts the trans fer pad 74; pipes (suction paths) 76A and 76B which communicate each suction cup 75 and a suction source 78; a valve V1; and a pressure gauge 79 that measures pressures in the pipes 76A and 76B. The diagnosis part 100 brings each suction cup 75 into contact with an upper surface to which the suction cup 75 can be sucked, and determines that the suction cup 75 and the pipes 76A and 76B are normal when an absolute value |P| of a negative pressure P measured by the pressure gauge 79 exceeds a preset value |P0| when the suction cup 75 is communicated to the suction source 78, and determines that the suction cup 75 and the pipes 76A and 76B are abnormal when it does not exceed the preset value |P0|.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a processing apparatus including a transfer mechanism for sucking and holding a workpiece such as a wafer by at least four suction pads and transferring it.

Background Art

[0002] For example, in a processing apparatus for processing a thin disk-shaped wafer, a work set in which a tape is attached to a ring frame and the wafer is sucked and held by a transfer mechanism and transferred to a predetermined position is performed. Here, the transfer mechanism includes a transfer pad having at least four suction pads for sucking the upper surface of the wafer as the workpiece, a lifting mechanism for lifting and lowering the transfer pad, a suction path for communicating the suction pad with a suction source, and a valve provided in the suction path (see, for example, Patent Document 1).

[0003] In such a transfer mechanism, by opening the valve and connecting at least four suction pads to the suction source via the suction path, a suction force (negative pressure) is generated in each suction pad to suck and hold the work set.

[0004] However, when the suction pad deteriorates or air leakage (leak) occurs in the suction path that connects the suction pad to the suction source, sufficient suction force cannot be generated in the suction pad, and the work set drops from the transfer pad during transfer, and the wafer attached to the ring frame by the tape in this work set is damaged. Therefore, the suction pads are periodically replaced with new ones.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] However, currently, there is no established method for checking for air leaks from suction cups, suction channels, or other joints. For example, it is impossible to accurately determine when a suction cup should be replaced. This can lead to wasteful replacement of suction cups that are still perfectly usable.

[0007] The present invention has been made in view of the above problems, and its purpose is to provide a processing device that can easily and reliably check for air leaks from suction cups and suction passages of a conveying mechanism and accurately determine the appropriate time for replacing suction cups, piping, etc. [Means for solving the problem]

[0008] To achieve the above objective, the present invention provides a processing apparatus comprising: a chuck table for holding a workpiece on a holding surface; processing means for processing the workpiece held on the holding surface; a transport mechanism for loading or unloading a workpiece from the holding surface; and a diagnostic unit, wherein the transport mechanism comprises: a transport pad having at least four suction cups for sucking the upper surface of a workpiece; a lifting mechanism for raising and lowering the transport pad; a suction passage for connecting the suction cups to a suction source; a valve provided in the suction passage; and a pressure gauge for measuring the pressure in the suction passage between the suction cups and the valve, and the diagnostic unit makes contact with the upper surface on which at least four suction cups can suck, and when the absolute value of the negative pressure measured by the pressure gauge after connecting the suction cups to the suction source exceeds a preset value When the valve is closed, and the absolute value of the negative pressure measured by the pressure gauge after a predetermined time has elapsed since the valve was closed exceeds a preset value, The system is characterized in that it determines that the suction cup and the suction path are abnormal unless they are functioning normally and exceed a preset value. [Effects of the Invention]

[0009] According to the present invention, the diagnostic unit opens a valve to connect the suction cups to a suction source while the suction cups are in contact with at least four suction cups of the transport mechanism, and measures the pressure in the suction passage using a pressure gauge. If the absolute value of the pressure (negative pressure) measured by this pressure gauge exceeds a preset value (absolute value of negative pressure), it is determined that the suction cups and suction passage are normal, and if it does not exceed the preset value, it is determined that the suction cups and suction passage are abnormal. This provides the advantage of being able to easily and reliably check for air leaks from the suction cups and suction passage of the transport mechanism and accurately determine the appropriate replacement time for suction cups, piping, etc. [Brief explanation of the drawing]

[0010] [Figure 1] This is a perspective view of a cutting apparatus, which is one embodiment of the processing apparatus according to the present invention. [Figure 2] This is a partial perspective view showing a leak check being performed on the first transport mechanism using the frame guide of the cutting apparatus according to the present invention. [Figure 3] This flowchart shows the procedure for leak checking by the diagnostic unit in the cutting apparatus according to the present invention. [Figure 4] This is a time chart showing the time change of suction pressure during a leak check of the first transport mechanism in the cutting apparatus according to the present invention. [Figure 5] This is a partial perspective view showing a leak check being performed on the chuck table of the cutting apparatus according to the present invention. [Figure 6] This is a partial perspective view showing a leak check being performed on the spinner table of the cutting apparatus according to the present invention. [Modes for carrying out the invention]

[0011] Embodiments of the present invention will be described below with reference to the accompanying drawings.

[0012] [Configuration of the processing equipment] First, the overall configuration of the cutting apparatus, which is one embodiment of the processing apparatus according to the present invention, will be described below with reference to Figure 1. In the following description, the left-right direction in Figure 1 will be the X-axis direction, the front-back direction will be the Y-axis direction, and the up-down direction will be the Z-axis direction.

[0013] Figure 1 is a perspective view of a cutting apparatus according to the present invention. The illustrated cutting apparatus 1 is a so-called dual dicer and comprises a cassette stage 10 on which a cassette 11 containing a plurality of worksets WS (only one is shown in Figure 1) including a wafer W which is the workpiece, a pull-out mechanism 20 for pulling out the worksets WS from the cassette 11 placed on the cassette stage 10, a pair of frame guides 30 for temporarily placing the worksets WS pulled out by the pull-out mechanism 20, and the worksets WS The main components include a chuck table 40 for holding the wafer, a processing means 50 for cutting the wafer W held on the chuck table 40, a first transport mechanism 70 for loading a work set WS into the chuck table 40 and a second transport mechanism 80 for unloading the work set WS from the chuck table 40, a spinner cleaning mechanism 90 for cleaning the wafer W after cutting, and a diagnostic unit 100 (see Figure 2) for diagnosing the presence or absence of leaks (whether normal or abnormal) in leak checks of the first transport mechanism 70 and the second transport mechanism 80.

[0014] Next, we will describe the main components of the cutting apparatus 1: the cassette stage 10, the pull-out mechanism 20, the frame guide 30, the chuck table 40, the machining means 50, the first and second transport mechanisms 70 and 80, the spinner cleaning mechanism 90, and the diagnostic unit 100.

[0015] (Cassette Stage) The cutting device 1 shown in Fig. 1 includes a base 2 that supports each component. In the central part of the base 2 in the Y-axis direction, a rectangular opening 3 that is long in the X-axis direction is open. At the front (-Y-axis direction) right (+X-axis direction) corner of this opening 3, a cassette stage 10 that moves up and down in the vertical direction (Z-axis direction) by a lifting mechanism (not shown) is provided. And on the upper surface of this cassette stage 10, a rectangular box-shaped cassette 11 that houses a plurality of workpiece sets WS (only one is shown in Fig. 1) including a disk-shaped wafer W as a workpiece is arranged. In Fig. 1, for convenience of explanation, only the outline of the cassette 11 is shown by a dashed line.

[0016] Here, the wafer W has its surface (the upper surface in Fig. 1) partitioned into a number of rectangular regions by cutting planned lines called streets arranged in a grid pattern, and devices such as ICs and LSIs are respectively formed in each rectangular region. And by cutting the wafer W on which such a number of devices are formed along the streets, a plurality of semiconductor chips are formed. Note that a workpiece set WS in which the wafer W and the ring frame F are integrated by attaching a tape T to both is configured.

[0017] (Withdrawal mechanism) The withdrawal mechanism 20 is a mechanism that withdraws one workpiece set WS from the cassette 11 in the +Y-axis direction (rearward), and includes a ball screw shaft 21 and a guide rail 22 that are arranged vertically and parallel to each other along the Y-axis direction (front-rear direction) on the +X-axis direction end surface (right end surface) of the base 2, and an inverted L-shaped withdrawal arm 23 that moves in the Y-axis direction (front-rear direction) along these ball screw shaft 21 and guide rail 22.

[0018] Here, an electric motor 24, which is a drive source, is provided at one axial end (the left end in FIG. 1) of the ball screw shaft 21, and the other axial end (the right end in FIG. 1) is rotatably supported by a bearing 25 on the base 2. And the lower end of the vertical portion 23a of the draw arm 23 is slidably inserted and supported by the guide rail 22, and the ball screw shaft 21 is screwed and inserted through the middle portion in the height direction of the vertical portion 23a. Further, a holding portion 26 for holding the workpiece set WS is provided at the tip of the horizontal portion 23b that bends vertically from the upper end of the vertical portion 23a of the draw arm 23 and extends horizontally in the -X-axis direction (leftward).

[0019] (Frame guide) The frame guides 30 are a pair of left and right members bent in an inverted L shape for temporarily placing the workpiece set WS drawn out from the cassette 11 by the drawing mechanism 20. These frame guides 30 can move in opposite directions in the left-right direction (X-axis direction) along the slit-shaped guide holes 2a formed linearly in the X-axis direction (left-right direction) on the upper surface of the base 2. That is, as shown in FIG. 2, the vertical portions 30a of each frame guide 30 are respectively inserted through the guide holes 2a, and from the upper ends of the vertical portions 30a, the horizontal portions 30b extend horizontally and parallel to each other in the +Y-axis direction (rearward). Here, the pair of frame guides 30 move in opposite directions along the X-axis direction (left-right direction) by a moving mechanism (not shown) provided inside the base 2, so that the distance between them expands or contracts.

[0020] (Chuck table) The chuck table 40 is a disk-shaped member for holding the workpiece set WS, and is arranged on the upper surface of the base 2 such that the holding surface (upper surface) is exposed in the opening 3. And around this chuck table 40, four clamps 41 for fixing the ring frame F (see FIG. 1) of the workpiece set WS from four directions are arranged at equal angular pitches (90° pitch) in the circumferential direction.

[0021] Here, the chuck table 40 is rotated around a vertical axis by a rotational drive mechanism (not shown) located below it, and can reciprocate along the X-axis direction (left-right direction) by an X-axis direction movement mechanism (not shown) located below it. The area around the chuck table 40 in the opening 3 is covered by a rectangular plate-shaped cover 4 that moves together with the chuck table 40, and both sides (left and right) of the cover 4 in the X-axis direction of the opening 3 are covered by bellows-shaped expandable covers 5 that move and expand along with the cover 4 in the X-axis direction. Therefore, the opening 3 of the base 2 is always closed by the cover 4 and the expandable cover 5, regardless of the position of the chuck table 40 on the X-axis, and foreign matter and other objects are reliably prevented from entering the base 2 through the opening 3.

[0022] (Processing means) The cutting apparatus 1 according to this embodiment, which is a dual dicer, includes a first cutting unit 51 and a second cutting unit 52 arranged side by side on the left side (-X axis side) of the base 2 as processing means (cutting means). These first cutting unit 51 and second cutting unit 52 are arranged opposite each other on both the front and rear sides (-Y axis side and +Y axis side) of an opening 3 that opens on the upper surface of the base 2, and imaging units 53 are attached to these first cutting unit 51 and second cutting unit 52, respectively. Here, each imaging unit 53 detects the street position by imaging the wafer W held on the holding surface of the chuck table 40.

[0023] Furthermore, the first cutting unit 51 and the second cutting unit 52 can move up and down in the Z-axis direction (cutting feed direction) by a pair of front and rear Z-axis direction movement mechanisms 55, and can move forward and backward in the Y-axis direction (indexing feed direction) by a pair of front and rear Y-axis direction movement mechanisms 60.

[0024] Here, each Z-axis movement mechanism 55 includes a pair of Z-axis guide rails 56 arranged perpendicularly and parallel to each other in front of and behind a rectangular plate-shaped slider 61, a lifting plate 57 that can move up and down along these Z-axis guide rails 56, a rotatable Z-axis ball screw shaft 58 arranged perpendicularly between the pair of Z-axis guide rails 56, and a forward and reverse-rotating Z-axis pulse motor 59 that rotates the Z-axis ball screw shaft 58. The first cutting unit 51 and imaging unit 53 and the second cutting unit 52 and imaging unit 53 are attached to the lower part of each lifting plate 57. A nut member (not shown) is provided protruding from the back surface of each lifting plate 57, and the Z-axis ball screw shaft 58 is screwed into and inserted through this nut member.

[0025] In the Z-axis movement mechanism 55 configured as described above, when the Z-axis pulse motor 59 is driven and the Z-axis ball screw shaft 58 rotates in forward and reverse directions, the lifting plate 57, which has a nut member (not shown) protruding from it that screws onto the Z-axis ball screw shaft 58, moves up and down along a pair of Z-axis guide rails 56. As a result, the first cutting unit 51 and imaging unit 53 and the second cutting unit 52 and imaging unit 53, which are attached to each lifting plate 57, also move up and down along the Z-axis direction (cutting feed direction).

[0026] Furthermore, each of the front and rear pairs of Y-axis movement mechanisms 60 is equipped with a slider 61, and these sliders 61 are each movable along the Y-axis along a pair of upper and lower Y-axis guide rails 63 that are arranged parallel to each other along the Y-axis direction (front-to-back direction) on the front of a gate-shaped column 62 erected vertically on the base 2.

[0027] In the pair of front and rear Y-axis movement mechanisms 60, a pair of rotatable Y-axis ball screw shafts 64 are positioned between a pair of upper and lower Y-axis guide rails 63, arranged along the Y-axis direction (front and rear direction). Nut members (not shown), which protrude from the back surfaces of each of the front and rear sliders 61, are screwed onto these Y-axis ball screw shafts 64. In addition, one axial end of each Y-axis ball screw shaft 64 is connected to a Y-axis pulse motor 65 (only one is shown in Figure 1), which is a rotation drive source.

[0028] Therefore, in each Y-axis movement mechanism 60, when the Y-axis pulse motor 65 is driven to rotate the Y-axis ball screw shaft 64 in forward and reverse directions, a pair of front and rear sliders 61, each having a nut member (not shown) protruding from them that screws onto the Y-axis ball screw shafts 64, can move along the Y-axis guide rail 63 in the Y-axis direction (indexing feed direction) together with the lifting plate 57. As a result, the first cutting unit 51 and imaging unit 53 and the second cutting unit 52 and imaging unit 53, each attached to the lifting plate 57, can move along the Y-axis guide rail 63 in the Y-axis direction (indexing feed direction).

[0029] As described above, in the cutting apparatus 1 shown in Figure 1, the chuck table 40 and the wafer W (workset WS) held therein are movable along the X-axis direction (left-right direction), and the first cutting unit 51 and imaging unit 53 and the second cutting unit 52 and imaging unit 53 are movable along the Y-axis direction (front-back direction) and the Z-axis direction (up-down direction), respectively.

[0030] (First and second transport mechanisms) The first transport mechanism 70 is used to transport the work set WS, which has been pulled out from the cassette 11 by the pull-out mechanism 20 and temporarily placed on a pair of left and right frame guides 30, to the chuck table 40 by suction and holding. It can move up and down in the Z-axis direction (vertical direction) by the lifting mechanism 71 shown in Figure 2, and can also move horizontally on the XY plane by a moving mechanism (not shown).

[0031] As shown in detail in Figure 2, the first transport mechanism 70 includes an H-shaped transport pad 74 attached to the tip of an L-shaped stay 73 which is attached to the lower end of a vertical rod 72, and suction cups 75 are attached to each of the four corners of the transport pad 74.

[0032] As shown in Figure 2, each suction cup 75 is formed into a hollow frustoconical shape with an open bottom using an elastic material such as rubber. A flexible pipe (suction channel) 76A is connected to each of the four suction cups 75, and the four pipes (suction channels) 76A are joined by a joint 77 to form a single pipe (suction channel) 76B. The pipe (suction channel) 76B is connected to a suction source 78 such as a vacuum pump, and a valve V1 is provided in the middle of this pipe 76B to selectively connect and disconnect the communication between each suction cup 75 and the suction source 78. A pressure gauge (pressure sensor) 79 is provided between the joint 77 of pipe 76B and the valve V1 to measure the pressure (negative pressure) inside the pipes (suction channels) 76A and 76B. Valve V1 and pressure gauge 79 are electrically connected to the diagnostic unit 100. The pressure measured by the pressure gauge 79 is transmitted to the diagnostic unit 100, and as described later, the diagnostic unit 100 diagnoses whether there is an air leak (normal or abnormal) from the suction cup 75 or the piping (suction passages) 76A, 76B, etc., based on the pressure measurement transmitted from the pressure gauge 79.

[0033] The second transport mechanism 80 suction-holds the workset WS, which includes wafers W that have undergone predetermined cutting by the first cutting unit 51 and the second cutting unit 52, and transports it from the chuck table 40 to the spinner table 91 of the spinner cleaning mechanism 90, which will be described later. Its basic configuration is the same as that of the first transport mechanism 70.

[0034] In other words, as shown in Figure 6, the second transport mechanism 80 can move up and down in the Z-axis direction (vertical direction) by the lifting mechanism 81, and can also move horizontally on the XY plane by a moving mechanism (not shown). Furthermore, as shown in detail in Figure 6, the second transport mechanism 80 is equipped with an H-shaped transport pad 84 attached to a stay 83 which is attached to the lower end of a vertical rod 82, and suction cups 85 are attached to each of the four corners of the transport pad 84.

[0035] Here, a flexible pipe (suction channel) 86A is connected to each of the four suction cups 85, and the four pipes (suction channels) 86A are joined by a joint 87 and connected to a single pipe (suction channel) 86B. The pipe (suction channel) 86B is connected to a suction source 88, and a valve V2 is provided in the middle of this pipe 86B to selectively connect and disconnect the communication between each suction cup 85 and the suction source 88. A pressure gauge (pressure sensor) 89 is provided between the joint 87 of pipe 86B and the valve V2 to measure the pressure (negative pressure) in the pipes (suction channels) 86A and 86B. Valve V2 and pressure gauge 89 are electrically connected to the diagnostic unit 100. The pressure measured by the pressure gauge 89 is transmitted to the diagnostic unit 100, and as described later, the diagnostic unit 100 diagnoses whether there is an air leak (normal or abnormal) from the suction cup 85 or the piping (suction passages) 86A, 86B, etc., based on the pressure measurement transmitted from the pressure gauge 89.

[0036] In this embodiment, the transport pad 74 of the first transport mechanism 70 and the transport pad 84 of the second transport mechanism 80 are each provided with four suction cups 75 and 85, respectively. However, the number of these suction cups 75 and 85 can be any number, as long as there are four or more.

[0037] (Spinner cleaning mechanism) The spinner cleaning mechanism 90 is for cleaning the wafer W after the cutting process is completed, and as shown in Figure 1, it is located behind and to the right of the opening 3 on the base 2. The spinner cleaning mechanism 90 includes a spinner table 91 that rotates while holding the work set WS (wafer W) by suction, and an injection nozzle (not shown) that sprays cleaning fluid from above onto the work set WS (wafer W) held by suction on the spinner table 91.

[0038] (Diagnostic Department) The diagnostic unit 100, shown in Figures 2, 5, and 6, checks for air leaks from the suction cups 75 of the first transport mechanism 70 and the suction channels 76A and 86B of the second transport mechanism 80, based on the absolute values ​​of the pressure (negative pressure) inside the pipes (suction channels) 76A and 76B and the suction cups 85 of the second transport mechanism 80, respectively, measured by pressure gauges 79 and 89 installed in the first transport mechanism 70 and the second transport mechanism 80. If the measured pressure (absolute value) exceeds a preset value (absolute value), it is diagnosed as normal because there is no air leak; if it does not exceed the preset value, it is diagnosed as abnormal because there is an air leak. Details of the diagnostic method will be described later.

[0039] [Operation of the cutting device] Next, the operation of the cutting device 1 configured as described above will be explained.

[0040] During the cutting process of the wafer W, the workpiece set WS is pulled out from the cassette 11 placed on the cassette stage 10 by the pull-out mechanism 20 and temporarily placed on a pair of frame guides 30. At this time, as shown in Figure 2, the pair of frame guides 30 move toward each other, narrowing the distance between them.

[0041] From the above state, when the first transport mechanism 70 moves upward towards the work set WS by a moving mechanism (not shown), the transport pad 74 of the first transport mechanism 70 is lowered in the -Z axis direction by the lifting mechanism 71 (see Figure 2), and the four suction cups 75 provided on the transport pad 74 come into contact with the upper surface of the ring frame F (see Figure 1) of the work set WS. Then, the valve V1 shown in Figure 2 is opened, and the suction cups 75 and the suction source 78 are connected via piping (suction passages) 76A and 76B, so that the suction cups 75 are sucked in by the suction source 78, generating negative pressure on the suction cups 75, and the work set WS is attracted to the suction cups 75 by this negative pressure. Subsequently, the lifting mechanism 71 raises the transport pad 74 along with the workpiece set WS in the +Z axis direction, and as the workpiece set WS moves away from the frame guide 30, a moving mechanism (not shown) moves the pair of frame guides 30 in a direction away from each other along the guide holes 2a of the base 2, and as shown in Figure 1, the distance between the two frame guides 30 increases, allowing the workpiece set WS to pass between these frame guides 30.

[0042] Next, the chuck table 40 moves downward along the +X axis direction relative to the workpiece set WS by an X-axis movement mechanism (not shown). From this position, the transport pad 74 is lowered in the -Z axis direction by the lifting mechanism 71 (see Figure 2), and the workpiece set WS held by the transport pad 74 is transferred to the chuck table 40. The workpiece set WS, once transferred to the chuck table 40, is then held by suction to the holding surface of the chuck table 40, and the chuck table 40, holding the workpiece set WS, moves in the -X axis direction relative to the X axis direction relative to an X-axis movement mechanism (not shown).

[0043] On the other hand, in the first cutting unit 51 and the second cutting unit 52 shown in Figure 1, once an image is obtained by imaging the surface of the wafer W with each imaging unit 53, the street to be cut is detected by pattern matching processing based on that image. Once the street of the wafer W is detected in this way, the Y-axis position of each cutting blade 51a of the first cutting unit 51 and the second cutting unit 52 (only one is shown in Figure 1) is determined by a pair of front and rear Y-axis movement mechanisms 90, and the Y-axis positions of these cutting blades 51a are aligned with the positions of the street to be cut.

[0044] Then, from the above state, the cutting blades 51a of the first cutting unit 51 and the second cutting unit 52 are each driven to rotate at high speed, and are lowered by a predetermined amount by a pair of front and rear Z-axis movement mechanisms 55, while the chuck table 40 and the work set WS (wafer W) held therein are moved in the X-axis direction by an X-axis movement mechanism (not shown). As a result, the wafer W is cut along the streets by the cutting blades 51a of the first cutting unit 51 and the second cutting unit 52. When this operation is performed along all streets in one direction, the chuck table 40 and the work set WS held therein are rotated by 90° by a rotation drive mechanism (not shown), and the wafer W is similarly cut along the other street perpendicular to the street where the cutting has been completed. When the cutting along all streets of the wafer W is completed, multiple semiconductor chips on which individual devices are mounted are obtained.

[0045] Once the cutting process on the wafer W is completed as described above, the workpiece set WS held on the chuck table 40 is transferred to the second transfer mechanism 80. That is, similar to the first transfer mechanism 70, the workpiece set WS is held in place by suction from four suction cups 85 provided on the transfer pad 84 of the second transfer mechanism 80, and then transferred to the spinner cleaning mechanism 90 and its spinner table 91.

[0046] The workpiece set WS, which has been transferred to the spinner table 91, is held in place by suction on the holding surface of the spinner table 91 and rotates with the spinner table 91 at a predetermined speed while being cleaned by a cleaning solution sprayed from a spray nozzle (not shown), thereby removing cutting debris that has adhered to the wafer W due to the cutting process.

[0047] [Leak check of the conveying mechanism] Next, we will explain the method for checking the leaks (diagnosing the presence or absence of air leaks) of the first conveying mechanism 70 and the second conveying mechanism 80.

[0048] (First transport mechanism) First, the method for checking the leak of the first transport mechanism 70 will be explained below based on Figures 2 to 4.

[0049] The leak check for this first transport mechanism 70 involves the diagnostic unit 100 diagnosing whether there are any air leaks in the four suction cups 75 provided on the transport pad 74 or in the piping (suction passages) 76A and 76B connecting each suction cup 75 to the suction source 78. The diagnostic procedure will be explained below according to the flowchart shown in Figure 3 and the time chart shown in Figure 4.

[0050] During the leak check of the first transport mechanism 70, as shown in Figure 2, the pair of frame guides 30 move toward each other, narrowing the distance between them, and the transport pad 74 is positioned above them. Then, the lifting mechanism 71 is driven (step S1 in Figure 3), and the transport pad 74 descends in the -Z axis direction.

[0051] As described above, when the transport pad 74 descends, it is determined whether the four suction cups 75 provided on the transport pad 74 have come into contact with the upper surface of the pair of frame guides 30 (step S2). If the four suction cups 75 come into contact with the upper surface (contact surface) of the frame guides 30 (step S2: Yes), the valve V1 is opened (step S3). Here, the width L1 of the upper surface (contact surface) of each frame guide 30 that each suction cup 75 comes into contact with is set to be larger than the maximum diameter φd of each suction cup 75 (L1 > φd), so that the entire surface of each suction cup 75 comes into contact with the upper surface of the frame guide 30. The downward movement of the transport pad 74 continues until the four suction cups 75 come into contact with the upper surface of the frame guides 30 (step S2 → step S1).

[0052] As described above, when valve V1 is opened (step S3), each suction cup 75 and the suction source 78 are connected by piping (suction passages) 76A and 76B, so negative pressure is generated in each suction cup 75. The elapsed time since valve V1 was opened is measured (step S4), and the pressure (negative pressure) P in the piping (suction passages) 76A and 76B is measured by pressure gauge 79 (step S5).

[0053] By the way, when valve V1 is opened, the pressure P in the piping (suction passage) 76A and 76B gradually decreases. Here, we consider three patterns of pressure P decrease, shown by solid line A, dashed line B, and chain line C in Figure 4. The pattern shown by solid line A is a pattern where there is no air leakage in the suction cup 75 or piping 76A and 76B, and the pressure P decreases rapidly. The pattern shown by dashed line B is a pattern where the decrease in pressure P is somewhat gradual due to slight air leakage in the suction cup 75 or piping 76A and 76B. The pattern shown by chain line C is a pattern where the decrease in pressure P is very gradual due to a large amount of air leakage in the suction cup 75 or piping 76A and 76B.

[0054] As described above, when the pressure P in the pipes 76A and 76B is measured by the pressure gauge 79, the diagnostic unit 100 determines whether the absolute value |P| of the measured pressure (negative pressure) P exceeds a preset absolute value |P0| (|P|>|P0|?) (step S6).

[0055] In the pattern shown by line A in Figure 4, at time t1, the absolute value of pressure P |P| exceeds the set value |P0| at point a in Figure 4 and decreases to pressure P1. In the pattern shown by dashed line B in Figure 4, at time t2, which is slightly later than time t1, the absolute value of pressure P |P| exceeds the set value |P0| at point b in Figure 4 and decreases to pressure P1.

[0056] Therefore, in the two patterns described above, the absolute value |P| of the pressure P measured by the pressure gauge 79 exceeds the set value |P0| at times t1 and t2, respectively (Step S6: Yes), so the diagnostic unit 100 closes the valve V1 at times t1 and t2, respectively (Step S7), and measures the elapsed time since closing the valve V1 (Step S8).

[0057] As described above, when valve V1 is closed, the communication between each suction cup 75 and the suction source 78 via the piping (suction passages) 76A and 76B is cut off, and the suction of air in the piping 76A and 76B to the suction source 78 is stopped. However, it is determined whether a predetermined time (for example, 10 seconds) ΔT1 has elapsed since valve V1 was closed (step S9). If the predetermined time ΔT1 has elapsed (step S9: Yes), it is determined whether the absolute value |P| of the pressure P in the piping 76A and 76B, as measured by the pressure gauge 79, has exceeded a predetermined set value |P0| (step S10). In the pattern shown by solid line A in Figure 4, the pressure P remains constant at time t3 after the predetermined time ΔT1 has elapsed. Therefore, the absolute value |P| of the pressure P at time t3 after the predetermined time ΔT1 has elapsed remains at a value P1 that exceeds the set value |P0|, as shown at point c, and the determination result in step S10 is Yes. This means that there is no air leak from the suction cup 75 or the pipes 76A and 76B (in fact, no inflow of outside air into the suction cup 75 or the pipes 76A and 76B), so the diagnostic unit 100 diagnoses that the suction cup 75 and the pipes 76A and 76B are normal and can be used continuously (step S11), and terminates the series of diagnostic processes (step S12).

[0058] In contrast, in the pattern shown by the dashed line B in Figure 4, the absolute value |P| of the pressure P measured by the pressure gauge 79 at time t4, after a predetermined time ΔT1 has elapsed since closing the valve V1, does not exceed the set value |P0| as shown by point d in Figure 4, so the judgment result in step S10 is No. This means that there is a slight air leak from the suction cup 75 and the pipes 76A and 76B, so the diagnostic unit 100 diagnoses that the suction cup 75 and the pipes 76A and 76B are abnormal and need to be replaced (step S13), and terminates the series of diagnostic processes (step S12).

[0059] Unlike the patterns shown by solid line A and dashed line B in Figure 4, the pattern shown by dashed line C shows a very slow decrease in pressure P measured by pressure gauge 79, suggesting that a large amount of air leakage is occurring in the suction cup 75 and pipes 76A and 76B. Assuming such a case, the diagnostic unit 100 determines whether the time elapsed since opening the valve V1 has exceeded the predetermined time ΔT2 shown in Figure 4 (step S14) if the absolute value |P| of the pressure P measured by the pressure gauge 79 does not exceed the set value |P0| after opening the valve V1 (step S6: No). If the predetermined time ΔT2 has not elapsed (step S14: No), the process from steps S4 to S6 is repeated. If, even at time t5 after the predetermined time ΔT2 has elapsed, the absolute value |P| of the pressure P measured by the pressure gauge 79 shows P3 as indicated by point e in Figure 4 and does not exceed the predetermined value |P0| (step S14: Yes), the diagnostic unit 100 diagnoses that the suction cup 75 and the pipes 76A and 76B are abnormal and need to be replaced (step S13), and terminates the series of diagnostic processes (step S12). In this embodiment, the predetermined elapsed time ΔT2 after valve V1 is opened is set to be longer than the predetermined elapsed time ΔT1 after valve V1 is closed (ΔT2 > ΔT1). However, this can be reversed (ΔT2 < ΔT1) or they can be the same (ΔT1 = ΔT2). As described above, in this embodiment, the diagnostic unit 100 opens the valve V1 with the four suction cups 75 of the first transport mechanism 70 in contact with the flat upper surface of the frame guide 30, connects the suction cups 75 to the suction source 78, and measures the pressure P of the pipes 76A and 76B using the pressure gauge 79. If the absolute value |P| of the pressure (negative pressure) P measured by the pressure gauge 79 exceeds a preset value |P0|, the suction cups 75 or the pipes (suction passages) 76A and 76B are normal. If it does not exceed the preset value |P0|, the suction cups 75 or the pipes (suction passages) 76A and 76B are abnormal. This provides the advantage of being able to easily and reliably check for air leaks from the suction cups 75 and pipes (suction passages) 76A and 76B of the first transport mechanism 70 and accurately determine the appropriate replacement time for the suction cups 75 and pipes 76A and 76B.

[0060] In the above embodiment, the four suction cups 75 of the first conveying mechanism 70 were brought into contact with the flat upper surface of the frame guide 30 to perform a leak check of the suction cups 75 of the first conveying mechanism 70 and the pipes 76A and 76B. However, as shown in Figure 5, the four suction cups 75 of the first conveying mechanism 70 may also be brought into contact with the flat annular portion (contact surface) 40a on the outer circumference of the chuck table 40 to perform a leak check of the suction cups 75 and the pipes (suction passages) 76A and 76B using the same method as described above. In this case, the width L2 of the annular portion 40a on the outer circumference of the upper surface of the chuck table 40 is set to be larger than the maximum diameter φd of each suction cup 75 (L2 > φd). In Figure 5, the same elements as those shown in Figure 2 are denoted by the same reference numerals, and further explanation of these is omitted. Alternatively, instead of contacting the annular portion 40a on the outer circumference of the upper surface of the chuck table 40, the suction cup 75 may be brought into contact with the support surface on which the clamp 41 supports the frame F, and the leak check of the suction cup 75 and the pipes (suction passages) 76A and 76B may be performed using the same method as described above.

[0061] (Second transport mechanism) Leak checks of the second conveying mechanism 80 can be performed in the same way as leak checks of the first conveying mechanism 70.

[0062] In other words, in the leak check of the second transport mechanism 80, as shown in Figure 6, the four suction cups 85 of the second transport mechanism 80 are brought into contact with the flat annular portion (contact surface) 91a on the outer circumference of the spinner table 91 of the spinner cleaning mechanism 90, and a leak check of the suction cups 75 and piping (suction passages 86A, 86B) is performed using the same method as described above. In this case, the width L3 of the annular portion 91a on the outer circumference of the upper surface of the spinner table 91 is set to be larger than the maximum diameter φd of each suction cup 85 (L3 > φd). Note that in Figure 6, the same elements as those shown in Figures 2 and 5 are denoted by the same reference numerals, and further explanation of these is omitted. The first transport mechanism 70 may also transport the work set WS from the chuck table 40 to the spinner table 91 of the spinner cleaning mechanism 90.

[0063] By the way, although the above has described an embodiment of the present invention applied to a cutting device, the present invention also includes any other processing device that is equipped with a conveying mechanism for suction-holding and transporting a workpiece using suction cups.

[0064] Furthermore, in the above examples, the upper surface of the frame guide 30 and the annular portion 40a of the upper surface of the chuck table 40 were used as the contact surfaces that the suction cup 75 contacts when checking the first transport mechanism 70, and the annular portion 91a of the spinner table 91 was used as the contact surface that the suction cup 85 contacts when checking the second transport mechanism 80. However, any other flat surface can be used as the contact surface for these suction cups 75 and 85.

[0065] Furthermore, the present invention is not limited to the embodiments described above, and various modifications are possible within the scope of the technical idea described in the claims, specification, and drawings. [Explanation of Symbols]

[0066] 1: Cutting device (processing device), 2: Base, 2a: Guide hole, 3: Opening of the base, 4: Cover, 5: Extendable cover, 10: Cassette stage, 11: Cassette, 20: Drawer mechanism, 21: Ball screw shaft, 22: Guide rail, 23: Pull-out arm: 23a: Vertical part of the pull-out arm, 23b: Horizontal part of the pull-out arm, 24: Electric motor, 25: Bearing, 26: Holding part, 30: Frame guide, 30a: Vertical part of the frame guide, 30b: Horizontal section of frame guide, 40: Chuck table, 40a: Annular portion of the chuck table, 41: Clamp, 50: Machining means, 51: First cutting unit, 51a: Cutting blade, 52: Second cutting unit, 53: Imaging unit, 55: Z-axis movement mechanism, 56: Z-axis guide rail, 57: Lifting plate, 58: Z-axis ball screw shaft, 59: Z-axis pulse motor, 60: Y-axis movement mechanism, 61: Slider, 62: Column, 63: Y-axis guide rail, 64: Y-axis ball screw shaft, 65: Y-axis pulse motor, 70: First transport mechanism, 71: Lifting mechanism, 72: Rod, 73: Stay, 74: Transport pad, 75: Suction cup, 76A, 76B: Piping (suction path), 77: Joint, 78: Suction source, 79: Pressure gauge, 80: Second transport mechanism, 81: Lifting mechanism, 82: Rod, 83: Stay, 84: Conveyor pad, 85: Suction cup, 86A, 86B: Piping (suction path), 87: Joint, 88: Suction source, 89: Pressure gauge, 90: Spinner cleaning mechanism, 91: Spinner table, 91a: Annular portion of the spinner table, 100: Diagnostic section, φd: Maximum diameter of suction cup, F: Ring frame, L1: Width of the top surface of the ring frame, L2: Width of the annular part of the chuck table, L3: width of the annular portion of the spinner table, T: tape, V1, V2: valves. W: Wafer, WS: Workset

Claims

1. A processing apparatus comprising a chuck table for holding a workpiece on a holding surface, processing means for processing the workpiece held on the holding surface, a transport mechanism for loading or unloading a workpiece from the holding surface, and a diagnostic unit, The conveying mechanism comprises a conveying pad having at least four suction cups for sucking the upper surface of a workpiece, a lifting mechanism for raising and lowering the conveying pad, a suction passage connecting the suction cups to a suction source, a valve provided in the suction passage, and a pressure gauge for measuring the pressure in the suction passage between the suction cups and the valve. The diagnostic unit is a processing device that brings at least four suction cups into contact with an upper surface on which the suction cups can be attracted, connects the suction cups to the suction source and closes the valve when the absolute value of the negative pressure measured by the pressure gauge exceeds a preset value, and determines that the suction cups and the suction path are normal if the absolute value of the negative pressure measured by the pressure gauge after a predetermined time has elapsed since the valve was closed exceeds a preset value, and determines that the suction cups and the suction path are abnormal if the value does not exceed the preset value.

2. The workpiece is a work set in which a ring frame and a wafer are integrated by attaching tape to them, A cassette stage on which a cassette containing the workset is placed, A drawer mechanism for pulling out the work set from the cassette placed on the cassette stage, The system includes a frame guide for temporarily placing the workset pulled out by the pull-out mechanism, The frame guide has a contact surface having a larger area than the suction cup, The processing apparatus according to claim 1, wherein the diagnostic unit diagnoses whether the suction cups and the suction path are normal or abnormal by having at least four suction cups attract the contact surface of the frame guide.

3. The system includes a spinner cleaning mechanism that rotates a spinner table that holds the workpiece and sprays cleaning water onto the workpiece held on the spinner table to clean the workpiece. The spinner table has a contact surface having a larger area than the suction cup, The processing apparatus according to claim 1, wherein the diagnostic unit diagnoses whether the suction cups and the suction path are normal or abnormal by having at least four suction cups attract the contact surface of the spinner table.

4. The chuck table has a contact surface having a larger area than the suction cup, The processing apparatus according to claim 1, wherein the diagnostic unit diagnoses whether the suction cups and the suction path are normal or abnormal by having at least four suction cups attract the contact surface of the chuck table.

Images