Chip transport method
The described chip transport method addresses the challenge of holding small chips by employing a multi-step suction and lifting process, enhancing the reliability of chip transfer.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Patents
- Current Assignee / Owner
- DISCO CORP
- Filing Date
- 2022-08-08
- Publication Date
- 2026-06-11
Smart Images
Figure 0007873137000001 
Figure 0007873137000002 
Figure 0007873137000003
Abstract
Description
Technical Field
[0001] The present invention relates to a method for transporting chips that sucks and holds a plurality of chips for transportation.
Background Art
[0002] For example, in the manufacturing process of semiconductor devices, a package substrate such as a CSP substrate on which devices such as ICs and LSIs are formed in a plurality of regions partitioned in a grid pattern by a plurality of division planned lines orthogonal to each other is cut along the division planned lines by a cutting device, thereby dividing the package substrate into a plurality of individually packaged chips (see, for example, Patent Document 1).
[0003] A cutting device that cuts a package substrate along a division planned line includes a holding table that holds the package substrate and a transfer unit that unloads a plurality of chips from the holding table. Here, the transfer unit includes a transfer pad having a contact surface on which a plurality of suction holes corresponding to each of the plurality of chips held on the holding table are formed, and the plurality of chips are sucked and held by this transfer pad and transferred from the holding table to another place.
Prior Art Documents
Patent Documents
[0004]
Patent Document 1
Summary of the Invention
Problems to be Solved by the Invention
[0005] However, when sucking and holding a plurality of chips by a transfer pad, when the chips become small, there is a problem that all the chips cannot be sucked and held only by bringing the transfer pad into contact with the chip once for sucking and holding.
[0006] The present invention has been made in view of the above problems, and its purpose is to provide a chip transport method that can transport all chips by suction and holding them. [Means for solving the problem]
[0007] To achieve the above objective, the present invention provides a method for transporting a plurality of chips in a processing apparatus comprising: a holding table for holding a package substrate divided into a plurality of chips; a transport unit for transporting the plurality of chips from the holding table; and a control unit for controlling the transport unit, wherein the transport unit has a contact surface that contacts the plurality of chips, a plurality of suction holes formed on the contact surface corresponding to the plurality of chips, a suction path connecting the suction holes to a suction source, and a lifting unit for raising and lowering the contact surface, and the control unit performs a suction holding step of pressing the contact surface against the plurality of chips held on the holding table to suction and hold the chips, and a lifting step of raising the contact surface after the suction holding step, each performed two or more times. Furthermore, in the raising step, the height to which the contact surface is raised is less than the thickness of the tip. It is characterized by the following: [Effects of the Invention]
[0008] According to the present invention, the suction holding step, in which the contact surface of the transport unit is pressed against a plurality of chips held on a holding table to suction and hold the chips, and the lifting step, in which the contact surface is raised after the suction holding step, are each performed two or more times. This has the effect of increasing the probability that all chips will be suction-held and transported by the transport unit. [Brief explanation of the drawing]
[0009] [Figure 1] This is a partial perspective view of a cutting apparatus for carrying out the chip transport method according to the present invention. [Figure 2] This is a bottom view of the transport pad. [Figure 3] Figure 1 is a side view of the lifting unit of the cutting device. [Figure 4]This is a basic configuration diagram of a transport unit for carrying out a chip transport method according to the first embodiment of the present invention. [Figure 5] (a) to (d) are partial side views of the main parts of a transport unit showing the steps for carrying out the chip transport method according to the present invention (first and second embodiments). [Figure 6] This is a flowchart showing the procedure for carrying out the chip transport method according to the first embodiment of the present invention. [Figure 7] This is a basic configuration diagram of a transport unit for carrying out a chip transport method according to the second embodiment of the present invention. [Figure 8] This is a flowchart showing the procedure for carrying out the chip transport method according to the second embodiment of the present invention. [Modes for carrying out the invention]
[0010] Embodiments of the present invention will be described below with reference to the accompanying drawings.
[0011] [Basic Configuration of Cutting Machinery] First, the basic configuration of the cutting apparatus for implementing the chip transport method according to the present invention will be described below based on Figures 1 to 4. In the following description, the arrow directions shown in Figure 1 will be described as the X-axis direction (left-right direction), the Y-axis direction (front-back direction), and the Z-axis direction (up-down direction), respectively.
[0012] The cutting apparatus 1 shown in Figure 1 is a device for cutting a rectangular plate-shaped package substrate W, and comprises a holding table 10 for holding the package substrate W, a transport unit 20 for transporting the package substrate W contained in the cassette 2 to a temporary storage means 3, a first transport unit 30 for transporting the package substrate W temporarily placed in the temporary storage means 3 to the holding table 10, a cutting unit 40 for cutting the package substrate W held on the holding table 10 along the planned division line, and a cleaning unit for cleaning the upper surface of the package substrate W cut by the cutting unit 40. The main components of the system are a surface cleaning means 50, a bottom cleaning means 60 for cleaning the bottom surface of the package substrate W, a bottom drying means 70 for drying the bottom surface of the package substrate W cleaned by the bottom cleaning means 60, a second transport unit 80 for transporting the machined package substrate W held on the holding table 10 to the bottom drying means 70 via the bottom cleaning means 60, a dropping means 90 for dropping a plurality of divided chips C (see Figure 4) of the package substrate W placed on the bottom cleaning means 60 into the chip housing means 4, and a control unit 100.
[0013] Next, the configurations of the main components constituting the cutting apparatus 1, namely the holding table 10, the unloading unit 20, the first transport unit 30, the cutting unit 40, the upper surface cleaning means 50, the lower surface cleaning means 60, the lower surface drying means 70, the second transport unit 80, the dropping means 90, and the control unit 100, will be described in order below.
[0014] Here, the package substrate W is a CSP substrate in which devices such as ICs and LSIs are formed in multiple regions that are divided in a grid pattern by multiple division lines that are orthogonal to each other. The package substrate W is cut along the division lines by a cutting device 1, thereby dividing it into multiple individually packaged chips C (see Figure 4).
[0015] (Retention table) The holding table 10 is a rectangular plate-shaped member disposed substantially at the center of the base 1A as shown in FIG. 1. On the holding surface 11 (see FIG. 4) of its upper surface, circular hole-shaped suction holes (not shown) corresponding to a plurality of regions partitioned in a grid pattern of the package substrate W are respectively opened. And as shown in FIG. 4, these suction holes are connected to one suction passage 13 through a plurality of suction passages 12 formed in the holding table 10, and a pipe 14 is connected to the suction passage 13. Here, the pipe 14 branches into two branch pipes 14a and 14b. One branch pipe 14a is connected to a suction source 15 such as a vacuum pump via an electromagnetic on-off valve V1, and the other branch pipe 14b is connected to an air supply source 16 such as an air compressor via an electromagnetic on-off valve V2. Note that the electromagnetic on-off valves V1 and V2 are electrically connected to the control unit 100, and their opening and closing operations are respectively controlled by the control unit 100.
[0016] Also, as shown in FIG. 1, the holding table 10 is supported by a disk-shaped support member 17, and the support member 17 and the holding table 10 can rotate by a predetermined angle (90°) around a vertical central axis by a rotation drive mechanism (not shown).
[0017] And the holding table 10 and the support member 17 are movable along the X-axis direction (machining feed direction) by X-axis direction moving means (not shown), and can reciprocate between a machining position for cutting the package substrate W and a delivery position for delivering the package substrate W. Note that the X-axis direction moving means is constituted by a known ball screw mechanism or the like.
[0018] (Unloading unit) The unloading unit 20 is disposed at the +Y-axis direction end portion (rear end portion) on the base 1A as shown in FIG. 1, and takes out one package substrate W from a cassette 2 disposed in a column 1B standing at the -X-axis direction end portion (left end portion) of the base 1A, and functions to temporarily place this package substrate W on the temporary placing means 3.
[0019] (First conveying unit) The first transport unit 30 transports the package substrate W, which has been temporarily placed on the temporary placement means 3, to the holding table 10, and includes a suction pad 31 that holds the upper surface of the package substrate W by suction, an air cylinder mechanism 32 that supports the suction pad 31 and moves it up and down, an operating arm 33 that supports the air cylinder mechanism 32, and a moving means (not shown) that moves the operating arm 33 along the Y-axis direction (front and rear direction). Alternatively, instead of the air cylinder mechanism 32, a ball screw mechanism having a motor, a ball screw, and a guide may be used to move the suction pad 31 up and down.
[0020] Furthermore, an imaging means 34 is attached to the air cylinder mechanism 32 to detect the area of the package substrate W to be processed. This imaging means 34 is composed of optical means such as a microscope or a CCD camera, and transmits the captured image data to the control unit 100.
[0021] (Cutting unit) The cutting unit 40 is a unit for cutting a package substrate W held on a holding table 10 along a planned division line, and comprises a spindle housing 41 arranged along the indexing feed direction (Y-axis direction), a spindle (not shown) rotatably supported in the spindle housing 41, a cutting blade 42 mounted on the tip of the spindle, and cutting fluid supply nozzles (not shown) arranged on both sides of the cutting blade 42.
[0022] The spindle housing 41 is movable in the Y-axis direction (indexing feed direction) by a Y-axis moving means (not shown), and the spindle and cutting blade 42 (not shown) are rotated at a predetermined speed by a rotational drive source (not shown), such as a servo motor. In this embodiment, the cutting blade 42 is an electroformed blade in which diamond abrasive grains are fixed with nickel plating on a disc-shaped blade base made of aluminum. During the cutting of the package substrate W, cutting fluid is supplied from a cutting fluid supply nozzle (not shown) to the cutting portion between the cutting blade 42 and the package substrate W.
[0023] (Top surface cleaning means) As shown in Figure 1, in the X-axis direction (machining feed direction), between the cutting unit 40 and the holding table 10, that is, above the movement path of the holding table 10 along the X-axis direction, a top surface cleaning means 50 is provided to clean the top surface of the package substrate W, which has been divided into individual chips C by the cutting process performed by the cutting unit 40. This top surface cleaning means 50 cleans the top surface of the package substrate W after cutting, by spraying cleaning water onto the top surface of the package substrate W held on the holding table 10.
[0024] (Bottom surface cleaning means) The bottom surface cleaning means 60 cleans the bottom surface of the package substrate W, which has been divided into individual chips C by the cutting process of the cutting unit 40, and is located on the -Y axis side (front side) of the holding table, as shown in Figure 1. This bottom surface cleaning means 60 includes a pair of rotatable cleaning rollers 61 and a cleaning water supply means (not shown) that supplies cleaning water to these cleaning rollers 61, and each cleaning roller 61 is made of a sponge or the like.
[0025] (Bottom surface drying means) The bottom surface drying means 70 dries the bottom surface of the package substrate W whose bottom surface has been cleaned by the bottom surface cleaning means 60, and as shown in Figure 1, it is arranged adjacent to the bottom surface cleaning means 60 in the Y-axis direction. This bottom surface drying means 70 includes a rectangular plate-shaped drying table 71 that suction and holds the package substrate W whose bottom surface has been cleaned by the bottom surface cleaning means 60, and a heating heater (not shown) as a heating means.
[0026] (Second transport unit) The second transport unit 80 is a unit for carrying out the chip transport method according to the present invention together with the holding table 10, and it sucks and holds individual chips C of the package substrate W that has been machined and held on the holding table 10, and transports these multiple chips C to the bottom drying means 70 via the bottom cleaning means 60.
[0027] Here, the second transport unit 80 is composed of a transport pad 81 that suction-holds the upper surfaces of a plurality of individually divided chips C of the machined package substrate W held on the holding table 10, an operating arm 82 that supports the transport pad 81, a moving means (not shown) that moves the operating arm 82 together with the transport pad 81 in the Y-axis direction (front-to-back direction), and a lifting unit 5 that raises and lowers the transport pad 81 and the operating arm 82 in the Z-axis direction (up and down direction).
[0028] The transport pad 81 is a rectangular plate-shaped member that is horizontally attached to the lower end of the operating arm 82. A rectangular contact surface 83 is attached to the lower surface of the transport pad 81, as shown in Figures 2 to 4. As shown in Figure 2, multiple (4 rows x 7 columns = 28) circular suction holes 83a are opened in a matrix pattern on this contact surface 83. The number of suction holes 83a can be arbitrarily set according to the number of chips C that are manufactured in separate parts.
[0029] As shown in Figure 4, the multiple suction holes 83a opening in the contact surface 83 are connected to a single suction passage 85 via multiple suction passages 84 formed in the contact surface 83, and a pipe 86 is connected to the suction passage 85. The pipe 86 is then connected to a suction source 87, such as a vacuum pump, via an electromagnetic valve V3. The electromagnetic valve V3 is electrically connected to the control unit 100, and its opening and closing operation is controlled by the control unit 100.
[0030] Furthermore, as shown in Figure 3, the lifting unit 5 is composed of a ball screw mechanism housed within column 1B (see Figure 1). This ball screw mechanism includes a vertical ball screw shaft 6 that is screwed into the operating arm 82, a servo motor 7 which is a rotational drive source connected to the upper end of the ball screw shaft 6, and a guide rail 8 that guides the lifting and lowering of the operating arm 82 and the transport pad 81 supported by it.
[0031] Therefore, when the servo motor 7 is activated and the ball screw shaft 6 is rotated forward and backward, the operating arm 82 that is screwed onto the ball screw shaft 6 moves up and down along the guide rail 8, and the transport pad 81 supported by the operating arm 82 moves up and down together with the operating arm 82.
[0032] (Method of insertion) As shown in Figure 1, the dropping mechanism 90 dries the upper surfaces of the multiple divided chips C of the package substrate W held on the drying table 71 of the lower drying mechanism 70, and drops these chips C into the input port 4a of the chip storage mechanism 4, which is located adjacent to the lower drying mechanism 70. The dropping mechanism 90 includes a hot air spray nozzle 91 that sprays hot air toward the upper surface of the chips C, a dropping brush 92 attached to the hot air spray nozzle 91, an air cylinder mechanism 93 that raises and lowers the hot air spray nozzle 91, an operating arm 94 that supports the air cylinder mechanism 93, and a moving mechanism (not shown) that moves the operating arm 94 in the Y-axis direction. A drawer 95 for inserting and removing a chip storage container (not shown) of the chip storage mechanism 4 is provided on the front wall (+X-axis end face) of the base 1A.
[0033] (Control Unit) The control unit 100 includes a CPU (Central Processing Unit) that performs calculations according to a control program, and memory such as ROM (Read Only Memory) and RAM (Random Access Memory). The control unit 100 receives imaging data from the imaging means 34 and controls the rotation drive mechanism (not shown) of the holding table 10, the unloading unit 20, the first transport unit 30, the cutting unit 40, the upper surface cleaning means 50, the lower surface cleaning means 60, the lower surface drying means 70, the second transport unit 80, the dropping means 90, and the like.
[0034] [Operation of cutting equipment] Next, the operation of the cutting device 1 configured as described above will be explained.
[0035] During the cutting process of the package substrate W by the cutting device 1, the package substrate W housed in the cassette 2 is removed by the unloading unit 20 and temporarily placed in the temporary storage means 3. In this temporary storage means 3, the package substrate W is aligned, and the aligned package substrate W is held by the first transport unit 30 and transported to the holding table 10, where it is held by suction on the holding table 10.
[0036] On the other hand, at the processing location, once an image is obtained by imaging the surface of the package substrate W using the imaging means 34, the planned division lines to be cut are detected by pattern matching processing based on that image. Once the planned division lines of the package substrate W are detected in this way, the position of the cutting blade 42 of the cutting unit 40 in the Y-axis direction (indexing direction) is determined, and the position of the cutting blade 42 in the Y-axis direction is aligned with the position of the planned division lines to be cut on the package substrate W by an index feeding means (not shown).
[0037] Then, from the above state, the cutting blade 42 is driven to rotate at high speed, and is lowered by a predetermined cutting amount by a lifting mechanism (not shown), while the holding table 10 and the package substrate W held therein move in the -X axis direction by an X-axis moving means (not shown). In addition, cutting fluid is supplied from a water supply source (not shown) to a cutting fluid nozzle, and the cutting fluid is sprayed from the cutting fluid nozzle toward the cutting blade 42.
[0038] Then, at the processing position, the package substrate W held on the holding table 10 is cut along the division lines by the cutting blade 42 while receiving a supply of cutting fluid. When the above cutting process on the package substrate W is completed along all the division lines in one direction, the holding table 10 and the package substrate W held thereon are rotated by 90° by a rotational drive mechanism (not shown), and cutting is similarly performed along the division lines in the other direction that are perpendicular to the division lines that have been cut. When cutting along all the division lines of the package substrate W is completed, the package substrate W is divided into multiple chips C, each on which a device is mounted.
[0039] Once the cutting process of the package substrate W by the cutting unit 40 is complete, the package substrate W is sucked and held by the second transport unit 80 and transported from the holding table 10 to the lower surface drying means 70 via the upper surface cleaning means 50 and the lower surface cleaning means 60. During this transport process, the upper and lower surfaces of the package substrate W are cleaned by the upper surface cleaning means 50 and the lower surface cleaning means 60, respectively. The package substrate W, with its upper and lower surfaces cleaned, is then sucked and held on the drying table 71 of the lower surface drying means 70, where the lower surface is dried by the lower surface drying means 70, and the upper surface is dried by the hot air sprayed from the hot air spray nozzle 91 of the drop-in means 90. The divided chips C of the package substrate W, with their upper and lower surfaces now dry, are then dropped into the input port 4a of the chip storage means 4 by the drop-in means 90.
[0040] Then, in the chip storage means 4, the multiple chips C that have been inserted are stored in a chip storage container (not shown), and a series of cutting operations on one package substrate W is completed. When the cutting operations on multiple package substrates W are performed continuously in this manner and a predetermined amount of chips C are stored in the chip storage container, the drawer 95 is pulled out and the chip storage container is removed, the chips C are recovered, and then the empty chip storage container is set in the chip storage means 4.
[0041] [Method for transporting chips] Next, an embodiment of the chip C transport method according to the present invention will be described.
[0042] The following describes an embodiment in which, in the cutting apparatus 1, a plurality of divided chips C of a package substrate W held by suction on a holding table 10 are held by suction using a second transport unit 80 and transported to a lower surface drying means 70.
[0043] <First Embodiment> The method for transporting the chip C according to the first embodiment is characterized by performing the following steps 1) suction and holding step and 2) lifting step two or more times (three times in this embodiment).
[0044] 1) Suction holding step: In the suction holding step, the control unit 100 initially sets the number of suction holding steps and lifting steps n to 0 (n=0) (step S1 in Figure 6). Next, the control unit 100 opens one of the electromagnetic valves V2 shown in Figure 4 and closes the other electromagnetic valve V1 (step S2). As a result, air is ejected from the air supply source 16 through the branch pipe 14b, the piping 14, and the suction passages 13 and 12, and then through multiple suction holes (not shown) that open onto the holding surface 11 of the holding table 10. This makes it easier for the multiple divided chips C of the package substrate W held on the holding surface 11 of the holding table 10 to detach from the holding surface 11.
[0045] In the above state, the transport pad 81 of the second transport unit 80 is positioned above the package substrate W as shown in Figure 5(a) (step S3 in Figure 6), the transport pad 81 is lowered by the lifting unit 5 shown in Figure 3, and as shown in Figure 5(b), the contact surface 83 of the transport pad 81 presses against the multiple chips C on the holding table 10, thereby attracting and holding these chips C to the contact surface 83 (step S4: suction holding step). At this time, the control unit 100 has opened the electromagnetic valve V3 shown in Figure 4, so the negative pressure from the suction source 87 reaches the suction hole 83a of the contact surface 83 (see Figure 2) via the piping 86 and connecting passages 85, 84. As a result, the multiple chips C on the holding table 10 are attracted and held to the contact surface 83 of the transport pad 81 by this negative pressure, but there are cases where not all chips C are attracted and held to the contact surface 83, and some chips C may remain on the holding surface 11 of the holding table 10.
[0046] 2) Ascending step: In the next ascending step, the transfer pad 81 is lifted by a predetermined height h as shown in FIG. 5(c) by the lifting unit 5 shown in FIG. 3 (step S5: ascending step). Here, the predetermined height h by which the transfer pad 81 is lifted is set to be less than the thickness t of the chip C (h < t). By setting the predetermined height h by which the transfer pad 81 is lifted to be less than the thickness t of the chip C, the chip C held by suction on the contact surface 83 of the transfer pad 81 and the chip C not held by suction overlap in the height direction by Δh as shown in FIG. 5(c). Therefore, the angle at which the bottom surface of the chip C not sucked by the contact surface 83 of the transfer pad 81 is held on the holding surface 11 of the holding table 10 is limited to 90° or less, preferably 30° or less, and it does not stand up between the contact surface 83 and the holding surface 11.
[0047] Next, the number of times n of the suction holding step (step S4) and the ascending step (step S5) is counted (n = n + 1) (step S6), and it is determined whether the counted number of times n has reached a preset number of times (in this embodiment, 3 times) (step S7). When the number of times n of the suction holding step (step S4) and the ascending step (step S5) has not reached the predetermined number of times (n = 3) (step S7: No), the suction holding step (step S4), the ascending step (step S5), and the counting of the number of times n (n = n + 1) are repeated. When the number of times n has reached the preset number of times (3 times) (step S7: Yes), the lifting unit 5 shown in FIG. 3 is driven and the transfer pad 81 is lifted by a height greater than the thickness t of the chip C as shown in FIG. 5(d) (step S8).
[0048] In this embodiment, the number of times n is repeated between the suction holding step (step S4) and the lifting step (step S5) is set to 3 (n=3). However, it has been empirically proven that by repeating the suction holding step and the lifting step 3 times, all the chips C can be suction-held to the contact surface 83 of the transport pad 81, as shown in Figure 5(d). However, this number n is not set uniformly depending on the size and number of chips C, but should be set to an appropriate number depending on the size and number of chips C if it is 2 or more times.
[0049] As a result of repeating the above suction-holding step and lifting step a predetermined number of times (3 times), as shown in Figure 5(d), the transport pad 81 with all the chips C held by suction on the contact surface 83 is transported to the lower drying means 70 shown in Figure 1 (step S9), and the series of transports of chips C by the transport method according to this embodiment is completed (step S10).
[0050] As described above, in this embodiment, the suction holding step, in which the contact surface 83 of the transport pad 81 is pressed against the plurality of chips C held on the holding surface 11 of the holding table 10 to suction and hold the chips C, and the lifting step, in which the transport pad 81 is raised after the suction holding step, are performed three times, so that all of the chips C can be suction-held and transported by the suction pad 81.
[0051] <Second Embodiment> Next, a second embodiment of the chip C transport method according to the present invention will be described with reference to Figures 7 and 8. In Figure 7, the same elements as those shown in Figure 4 are denoted by the same reference numerals, and further explanation of them will be omitted below.
[0052] In this embodiment, as shown in Figure 7, a pressure gauge 88 is installed in the middle of the piping 86, and the control unit 100 repeats the suction holding step and the lifting step described in the first embodiment if the absolute value |P| of the negative pressure P detected by this pressure gauge 88 is below a predetermined threshold |P0| (|P| < |P0|). In other words, if the absolute value |P| of the negative pressure P is below a predetermined threshold |P0| (|P| < |P0|), an air leak occurs because there are chips C that are not sucked onto the contact surface 83 of the transport pad 81 during the suction holding step. Therefore, in this embodiment, if the absolute value |P| of the negative pressure P is above a predetermined threshold |P0|, it is determined that all chips C are being sucked and held by the suction pad 81. However, in this embodiment, if the absolute value of the negative pressure P |P| remains below a predetermined threshold |P0| (|P| < |P0|) even after repeating the suction holding step and the lifting step a predetermined number of times (5 times in this embodiment), it is determined that the transport pad 81 is unable to suction and hold all the chips C for some reason, and an error is reported to interrupt the process.
[0053] The method for transporting the chip C according to this embodiment will be described below in accordance with the flowchart shown in Figure 8.
[0054] In the chip C transport method according to this embodiment, similar to the first embodiment, the control unit 100 sets the number of suction holding steps and lifting steps n to 0 (n=0) as an initial setting (step S11). Next, the control unit 100 opens one of the electromagnetic valves V2 shown in Figure 7 and closes the other electromagnetic valve V1 (step S12). As a result, air is ejected from the air supply source 16 from the branch pipe 14b through the piping 14 and suction passages 13, 12 and out of a plurality of suction holes (not shown) that open to the holding surface 11 of the holding table 10. Therefore, the plurality of divided chips C of the package substrate W held on the holding surface 11 of the holding table 10 become easier to detach from the holding surface 11.
[0055] In the above state, the transport pad 81 of the second transport unit 80 is positioned above the package substrate W as shown in Figure 5(a) (step S13), the transport pad 81 is lowered by the lifting unit 5 shown in Figure 3, and as shown in Figure 5(b), the contact surface 83 of the transport pad 81 presses against the multiple chips C on the holding table 10, thereby suction-holding these chips C to the contact surface 83 of the transport pad 81 (step S14: suction-holding step).
[0056] Next, the lifting step is performed in the same manner as in the first embodiment (step S15). That is, in the lifting step, the transport pad 81 is raised by the lifting unit 5 shown in Figure 3 by a predetermined height h, as shown in Figure 5(c).
[0057] When the above rising step (step S15) is performed, the negative pressure P in the pipe 86 is measured by the pressure gauge 88 shown in Figure 7 (step S16). Then, the number of times n has been performed in the suction holding step (step S14) and the rising step (step S15) is counted (n=n+1) (step S17), and it is determined whether the absolute value |P| of the negative pressure P in the pipe 86 measured by the pressure gauge 88 exceeds a predetermined threshold |P0| (step S18).
[0058] If the absolute value |P| of the negative pressure P in the piping 86 measured by the pressure gauge 88 exceeds a predetermined threshold |P0| (|P|>|P0|) (Step S18: Yes), it is determined that all the chips C are being held by suction on the contact surface 83 of the suction pad 81, and the lifting mechanism 5 shown in Figure 3 is driven, causing the transport pad 81 to rise to a height greater than the thickness t of the chips C, as shown in Figure 5(d) (Step S19). The transport pad 81, with all the chips C held by suction on the contact surface 83, is then transported to the lower drying means 70 shown in Figure 1 (Step S20), and the transport of the chips C by the transport method according to this embodiment is completed (Step S21).
[0059] On the other hand, if the absolute value |P| of the negative pressure P in the pipe 86 measured by the pressure gauge 88 does not exceed a predetermined threshold |P0| (|P| < |P0|) (step S18: No), it is determined whether the number of times n for the suction holding step and the rising step has reached 5 (step S22). If the number of times n for the suction holding step and the rising step has not reached 5 (step S22: No), the process of steps S14 to S18, which include the suction holding step and the rising step, is repeated.
[0060] Then, if the number of repetitions n of the suction holding step and the rising step reaches 5 (S22: Yes), that is, if the absolute value |P| of the negative pressure P in the pipe 86 measured by the pressure gauge 88 does not exceed a predetermined threshold |P0| (|P|<|P0|) even after repeating the suction holding step and the rising step 5 times, an error is displayed (step S23) and the process is terminated (step S21).
[0061] As described above, in this embodiment, if the absolute value |P| of the negative pressure P detected by the pressure gauge 88 is below a predetermined threshold |P0| (|P| < |P0|), the suction holding step and the lifting step are performed again, thereby achieving the effect that all the tips C can be suctioned, held, and transported by the suction pad 81.
[0062] In this embodiment, the upper limit for the number of repetitions n of the suction holding step and the lifting step is set to 5 times, but this upper limit for the number of repetitions n can be set to any number, as long as there are multiple such repetitions.
[0063] Furthermore, in this embodiment, the upper limit of the number of repetitions n of the suction holding step and rising step when the absolute value |P| of the negative pressure P in the pipe 86 measured by the pressure gauge 88 does not exceed a predetermined threshold |P0| (|P| < |P0|) is set to n = 5 (5 times). However, the time taken to repeat the suction holding step and rising step may be measured, and the suction holding step and rising step may be repeated until the measured time reaches the upper limit.
[0064] By the way, the above description has been an application of the present invention to a method for transporting chips C by a second transport unit 80 in a cutting apparatus 1 for cutting a package substrate W, but the present invention can be similarly applied to a method for transporting chips in a processing apparatus that processes any workpiece other than a package substrate W.
[0065] Furthermore, in the above embodiment, the pressure of the air ejected from the holding table 10 and the pressing force of the conveying pad 81 on the tip C were kept constant during the suction holding step. However, these air pressure and pressing force may be increased as the number of suction holding steps and lifting steps n increases.
[0066] 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]
[0067] 1: Cutting device, 1A: Base, 1B: Column, 2: Cassette, 3: Temporary placement means, 4: Chip storage means, 4a: Input slot, 5: Lifting unit, 6: Ball screw shaft, 7: Servo motor, 8: Guide rail, 10: Holding table, 11: Holding surface, 12,13: Suction path, 14: Piping, 14a,14b: Branch pipe, 15: Suction source, 16: Air supply source, 17: Support member, 20: Discharge means, 30: First transport unit, 31: Suction pad, 32: Air cylinder mechanism, 33: Operating arm, 34: Imaging means, 40: Cutting unit, 41: Spindle housing, 42: Cutting blade, 50: Upper surface cleaning means, 60: Lower surface cleaning means, 61: Cleaning roller, 70: Lower surface drying means, 71: Drying table, 80: Second conveying unit, 81: Conveying pad, 82: Operating arm, 83: Contact surface, 83a: Suction hole, 84, 85: Suction path, 86: Piping, 87: Suction source, 88: Pressure gauge, 90: Dropping mechanism, 91: Hot air spray nozzle, 92: Drop brush, 93: Air cylinder mechanism, 94: Operating arm, 95: Drawer, 100: Control unit, C: chip, h: lift height of the transport pad, Δh: chip overlap height. P: negative pressure, P0: negative pressure threshold, t: chip thickness, V1, V2, V3: solenoid valves. W: Package substrate
Claims
1. A holding table that holds a package substrate divided into multiple chips, A transport unit for unloading multiple chips from the holding table, A control unit that controls the transport unit, A chip transport method for transporting multiple chips in a processing apparatus equipped with, The transport unit is, A contact surface that contacts multiple chips, Multiple suction holes are formed on the contact surface corresponding to multiple chips, A suction path connecting the suction port and the suction source, A lifting unit that raises and lowers the contact surface, It has, The control unit is A suction holding step involves pressing the contact surface against a plurality of chips held on the holding table to hold the chips by suction, A lifting step is performed to raise the contact surface after the suction holding step, Perform each of these at least twice, A method for transporting a chip, characterized in that, in the raising step, the height to which the contact surface is raised is less than the thickness of the chip.
2. The transport unit is equipped with a pressure gauge for detecting the pressure in the suction passage. The chip transport method according to claim 1, characterized in that the control unit repeats the suction holding step and the lifting step if the absolute value of the negative pressure detected by the pressure gauge falls below a predetermined threshold.