Pickup method and pickup device

Abstract

To propose a new technique of picking up a chip after confirming the state of separation of the chip.SOLUTION: A pickup method for picking up a chip stuck onto a tape from the tape comprises: a pushing-up step of locating a chip via a tape with respect to a push-up mechanism including a suction part that has a suction surface for sucking and holding a rear surface of the tape and a push-up part that is arranged in the suction surface, has a pressing surface smaller than the chip to be picked up on the tip thereof and can freely ascend / descend, and pushing up the chip via the tape with the push-up part in such a state that the rear surface of the tape is sucked by the suction surface to separate the chip from the tape; an imaging step of forming a photographed image by imaging the rear surface side of the chip via the tape; a determination step of determining whether or not the chip is separated from the tape on the basis of the photographed image; and a pickup step of picking up the chip by holding the front surface side of the chip by a chip holding tool when determining that the chip is separated from the tape.SELECTED DRAWING: Figure 12

Description

[Technical Field]

[0001] The present invention relates to a method for picking up a chip attached to a tape. [Background technology]

[0002] Conventionally, as disclosed in Patent Document 1, for example, a method is known in which a chip attached to tape is pushed up from below by a push-up member to peel it off, and the upper side of the chip is suction-held by a chip holding member to pick up the chip.

[0003] When pushing up the chip from below, if stress acts locally on the chip, the chip may be damaged. The risk of damage is particularly high when the chip is thin, less than 100 μm.

[0004] From the above perspective, it is ideal to configure the area of ​​the pressing surface of the push-up member to correspond to the size of the chip, and to position the push-up member at the center of the chip and push it up, so that the chip is picked up without applying stress locally to the chip as much as possible.

[0005] In Patent Document 1, the push-up member is composed of multiple pressing parts, first to third, and after all of the push-up members are raised to a predetermined position, the pressing part closer to the center of the chip is raised in stages, resulting in a pyramidal push-up configuration by the multiple pressing parts. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2013-033850 Summary of the Invention [Problem to be solved by the invention]

[0007] According to conventional methods, the area of ​​the pressing surface of the push-up member needs to be set according to the size of the chip, and when picking up chips of different sizes, it is necessary to prepare a push-up member that corresponds to the size of the chip each time.

[0008] For this reason, in the past, it was necessary to produce multiple types of push-up members of different sizes and change the push-up members each time depending on the size of the chip.

[0009] Replacing the push-up members as described above requires a lot of labor and time for the replacement work, and furthermore, it involves the cost of producing and managing multiple types of push-up members, so improvements were needed.

[0010] Furthermore, in the past, after the push-up, there was no check to see if the chip had peeled off from the tape, so there was a concern that some areas of the chip might not actually peel off from the tape and might remain firmly attached.

[0011] If a portion of the chip remains firmly attached, stress acts locally when the upper surface of the chip is held by suction with the chip holding member, increasing the possibility of the chip being damaged.

[0012] The present invention has been made in view of the above, and proposes a new technique for picking up a chip after checking the state of chip detachment. [Means for solving the problem]

[0013] The problem to be solved by the present invention is as described above, and the means for solving this problem will now be described.

[0014] According to one aspect of the present invention, a pickup method for picking up a chip attached to a tape from the tape includes the following steps: a push-up step in which the chip is positioned via the tape using a push-up mechanism equipped with a suction section having a suction surface that suction-holds the back surface of the tape, and a push-up section that is arranged inside the suction surface and can be raised and lowered and has a pressing surface at its tip that is smaller than the chip to be picked up, and the push-up section pushes up the chip via the tape while the back surface of the tape is being sucked by the suction surface, thereby peeling the chip from the tape; an imaging step in which the back side of the chip is imaged via the tape to form an image; a determination step in which, based on the imaged image, it is determined whether the chip has peeled from the tape; and a pickup step in which, if it is determined that the chip has peeled from the tape, the front side of the chip is held by a chip holder and picked up.

[0015] Furthermore, according to one aspect of the present invention, the method further includes an additional pushing-up step of additionally pushing up the non-peeled portion if it is determined in the determining step that the chip has not been peeled off from the tape.

[0016] Furthermore, according to one aspect of the present invention, in the judgment step, the pushed-up points on the chip that have been pushed up by the push-up mechanism up until it is determined that the chip has peeled off from the tape are stored, and when picking up a chip of the same type as the chip attached to the tape, the push-up step is performed on the stored pushed-up points without performing the imaging step and the judgment step.

[0017] According to one aspect of the present invention, a pickup device that picks up a chip attached to a tape from the tape includes a push-up mechanism that includes a suction section having a suction surface that suction-holds the back surface of the tape, and a push-up section that is arranged inside the suction surface and can be raised and lowered and has a pressing surface at its tip that is smaller than the chip to be picked up; a positioning mechanism that positions the chip with respect to the push-up mechanism via the tape; a chip back surface imaging unit that images the back surface side of the chip via the tape to form an imaged image; a controller that determines whether the chip has detached from the tape based on the imaged image; and a pickup mechanism that holds the front surface side of the chip and picks it up, wherein the controller picks up the chip when it determines that the chip has detached from the tape.

[0018] Furthermore, according to one aspect of the present invention, the controller has a chip backside imaging unit control unit that controls the operation of the chip backside imaging unit, a memory unit that stores the captured image, an image processing unit that processes the captured image to identify peeled areas and non-peeled areas, a determination unit that determines whether the chip has been peeled from the tape and can be picked up, and a push-up position setting unit that selects the area at the non-peeled area where the chip should be pushed up, and repeats the pushing up of the non-peeled area sequentially until it is determined that the chip has been peeled.

[0019] Furthermore, according to one aspect of the present invention, the device further includes a map memory unit that stores the coordinates of the locations that have been pushed up until it is determined that peeling has occurred as map data, and when another chip is pushed up, the same locations as the pushed up locations included in the map data are pushed up. [Effects of the Invention]

[0020] The present invention has the following effects.

[0021] That is, according to one aspect of the present invention, the chip is peeled off from the tape by being pushed up multiple times by a push-up part having a pressing surface smaller than the chip to be picked up, so that it is possible to accommodate the pickup of chips of different sizes. Furthermore, since the chip is picked up after determining whether or not it has peeled off based on an image of the back side of the pushed-up chip, it is possible to prevent the occurrence of chip damage caused by picking up a chip in an unpeeled state.

[0022] Furthermore, according to one aspect of the present invention, by performing additional pushing up when it is determined that the chip has not been peeled off, the number of pushing ups required until peeling is minimized, thereby preventing the occurrence of chip damage due to the load being placed on the chip.

[0023] Furthermore, according to one aspect of the present invention, by using map data of the push-up location when it is determined that the chip has been peeled, it is possible to peel other chips in the future using the same push-up method, thereby eliminating the need for imaging and determination steps and improving the throughput of the pickup. [Brief explanation of the drawings]

[0024] [Figure 1] FIG. 2 is a perspective view of the pickup device, with some of the components omitted. [Figure 2] FIG. 2 is a perspective view of the pickup device, with some of the components omitted. [Figure 3] 10A and 10B are diagrams illustrating the configuration of a wafer unit that holds a wafer after cutting. [Figure 4] 1A and 1B are diagrams illustrating the imaging of a wafer by a wafer imaging camera. [Figure 5] 1A is a cross-sectional view showing a wafer unit arranged above a push-up mechanism, FIG. 1B is a cross-sectional view showing an enlarged portion of the push-up mechanism, and FIG. 1C is a cross-sectional view showing an enlarged portion of a push-up mechanism of another embodiment. [Figure 6] 5A is a diagram illustrating the relationship between the area of ​​the pressing surface of the push-up portion and the area of ​​the chip in the configuration of FIG. 5B. FIG. 5B is a diagram illustrating the relationship between the area of ​​the pressing surface of the push-up portion and the area of ​​the chip in the configuration of FIG. 5C. [Figure 7] FIG. 2 is a perspective view showing a pickup mechanism. [Figure 8] 1A is a diagram illustrating the pushing-up by the pushing-up part, and FIG. 1B is a diagram illustrating the peeling-off of the pushed-up part and the surrounding part. [Figure 9] FIG. 2 is a diagram showing a captured image and a configuration of a controller. [Figure 10] 1 is a flowchart showing steps of a pick-up method. [Figure 11] FIG. 10 is a diagram showing how the back side of the chip is imaged through the tape. [Figure 12] 10A and 10B are diagrams illustrating examples of captured images captured by repeated thrusting. [Figure 13] 10A and 10B are diagrams illustrating another example of captured images captured by repeated thrusting. [Figure 14] FIG. 10 is a diagram illustrating a pickup step. DETAILED DESCRIPTION OF THE INVENTION

[0025] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. 1 and 2 are diagrams showing the configuration of the pickup device 2. FIG. 1, the pickup device 2 includes a base 4 that supports the structural elements that make up the pickup device 2. A cassette mounting table 5 is provided at one corner of the base 4, and a cassette 5a is mounted on the cassette mounting table 5.

[0026] 1 accommodates, for example, a plurality of wafer units 11 as shown in FIG. 3. In the wafer unit 11, the back surface 13b of the wafer 13 is fixed to an annular frame 21 via tape 19, and the front surface 13a of the wafer 13 is exposed. The wafer 13 is singulated into chips 23 by cutting or the like to form division starting points along intended division lines 17 extending in mutually perpendicular directions. Devices 24 are formed on the front surface side of the chips 23.

[0027] 1, a temporary placement mechanism 10 capable of temporarily placing wafer units 11 in two tiers is provided adjacent to the cassette placement table 5. The temporary placement mechanism 10 includes a pair of guide rails 12 arranged parallel to each other. Each of the pair of guide rails 12 is configured to form two tiers of shelves, and includes a first support surface 12a and a second support surface 12b that are generally parallel to the X-axis direction (first horizontal direction, left-right direction) and the Y-axis direction (second horizontal direction, front-rear direction).

[0028] 1, each of the first support surfaces 12a is disposed above and overlaps with the second support surfaces 12b. The pair of first support surfaces 12a and the pair of second support surfaces 12b each support the lower surface of the end (annular frame 21) of the wafer unit 11. For example, the pair of first support surfaces 12a supports the wafer unit 11 transferred from the cassette mounting table 5, and the pair of second support surfaces 12b supports the wafer unit 11 transferred from the frame holding mechanism 14 described below.

[0029] 1, a frame holding mechanism 14 is provided at a position adjacent to the temporary placement mechanism 10. The frame holding mechanism 14 includes a frame support part 16 that supports the lower surface side of the annular frame 21, and a frame pressing part 18 that is disposed above the frame support part 16 and comes into contact with the upper surface side of the annular frame 21. The frame support part 16 and the frame pressing part 18 are each formed in an annular shape corresponding to the shape of the annular frame 21, and are disposed so as to overlap each other.

[0030] 1 is configured to be movable along the Z-axis direction (vertical direction, up-down direction). When the frame support part 16 is moved upward in a state in which the wafer unit 11 is positioned so that the annular frame 21 is supported by the frame support part 16, the annular frame 21 is sandwiched and fixed between the frame support part 16 and the frame pressing part 18.

[0031] Whether or not the annular frame 21 is properly fixed by the frame holding mechanism 14 can be confirmed, for example, by detecting whether or not the frame support portion 16 and the frame pressing portion 18 are electrically connected via the annular frame.

[0032] 1, a transfer mechanism 20 that transfers the wafer unit 11 between the cassette 5a and the frame holding mechanism 14 is provided above the temporary placement mechanism 10 and the frame support part 16. The transfer mechanism 20 is configured to be movable along the Y-axis direction and the Z-axis direction, and includes a first gripping part 22a and a second gripping part 22b that grip the annular frame 21 of the wafer unit 11 from above and below. The first gripping part 22a is provided on the cassette mounting table 5 side of the transfer mechanism 20, and the second gripping part 22b is provided on the frame holding mechanism 14 side of the transfer mechanism 20.

[0033] 1, when the wafer unit 11 is carried out of the cassette 5a, the transfer mechanism 20 is moved along the Y-axis direction toward the temporary placement mechanism 10 while the first gripping parts 22a grip the end of the wafer unit 11 housed in the cassette 5a. As a result, the wafer unit 11 is pulled out of the cassette 5a and placed on (the upper level of) a pair of first support surfaces 12a provided on the temporary placement mechanism 10. Thereafter, the gripping by the first gripping parts 22a is released.

[0034] Next, with the end of the wafer unit 11 on the cassette 5a side being gripped by the second gripping part 22b of the transport mechanism 20, the transport mechanism 20 is moved along the Y-axis direction toward the frame holding mechanism 14. As a result, the wafer unit 11 is transported between the frame support part 16 and the frame pressing part 18, and the annular frame 21 is supported by the frame support part 16.

[0035] 1 and 2, a cutout portion 18a is formed by cutting out the frame holding portion 18 on the temporary placement mechanism 10 side of the frame holding portion 18. This cutout portion 18a is configured to be large enough for the transport mechanism 20 to pass through. This prevents the transport mechanism 20 from coming into contact with the frame holding portion 18 when the wafer unit 11 is transported to the frame holding mechanism 14.

[0036] 1, after the wafer unit 11 is transported to the frame holding mechanism 14, the second holding part 22b releases the holding of the wafer unit 11, and the frame support part 16 moves upward. As a result, the annular frame 21 is sandwiched and fixed between the frame support part 16 and the frame pressing part 18.

[0037] 1 and 2, the frame holding mechanism 14 is supported by a positioning mechanism 30 that controls the position of the frame holding mechanism 14. The positioning mechanism 30 includes an X-axis movement mechanism 32 that moves the frame holding mechanism 14 along the X-axis direction, and a Y-axis movement mechanism 42 that moves the frame holding mechanism 14 along the Y-axis direction. The X-axis movement mechanism 32 and the Y-axis movement mechanism 42 control the horizontal position of the frame holding mechanism 14.

[0038] The X-axis movement mechanism 32 includes a pair of guide rails 34 arranged along the X-axis direction on the base 4. A ball screw 36 is provided between the pair of guide rails 34 and arranged generally parallel to the pair of guide rails 34. A pulse motor 38 that rotates the ball screw 36 is connected to one end of the ball screw 36.

[0039] A moving block 40 is slidably disposed on the pair of guide rails 34. A nut portion (not shown) is provided on the lower surface (back surface side) of the moving block 40, and this nut portion is threadedly engaged with the ball screw 36. When the ball screw 36 is rotated by the pulse motor 38, the moving block 40 moves in the X-axis direction along the pair of guide rails 34.

[0040] The Y-axis movement mechanism 42 includes a pair of guide rails 44 arranged along the Y-axis direction on the moving block 40. A ball screw 46 is provided between the pair of guide rails 44 and arranged generally parallel to the pair of guide rails 44. A pulse motor 48 that rotates the ball screw 46 is connected to one end of the ball screw 46.

[0041] 1, the frame holding mechanism 14 is slidably disposed on a pair of guide rails 44. A nut portion (not shown) is provided on a support portion 14f of the frame holding mechanism 14, and this nut portion is threadedly engaged with a ball screw 46. When the ball screw 46 is rotated by a pulse motor 48, the frame holding mechanism 14 moves in the Y-axis direction along the pair of guide rails 44.

[0042] 1 and 2, the moving block 40 is configured in a plate shape, and an opening 41 that penetrates in the vertical direction is formed below the frame holding mechanism 14. This opening 41 allows the pushing-up mechanism 50, which will be described later, to push up from below.

[0043] A rectangular opening 4b is provided in the region between the pair of guide rails 36 in the base 4. A cylindrical push-up mechanism 50 is provided inside this opening 4b to push up the chips 23 (FIG. 3) included in the wafer 13 of the wafer unit 11 from the bottom side upward. The push-up mechanism 50 is connected to a lifting mechanism (not shown) comprised of a motor or the like, and moves up and down along the Z-axis direction.

[0044] 1 and 2, a chip backside imaging unit 7 is provided inside the opening 4b for imaging the backside of the chip 23 (FIG. 3) through the tape 19 from below the wafer unit 11. The chip backside imaging unit 7 is configured with, for example, a visible light camera, and images the backside of the chip 23 through the tape 19, which is translucent.

[0045] The chip backside imaging unit 7 may be configured to be movable under the control of the controller 1, in addition to being fixed in position inside the opening 4b.

[0046] With the annular frame 21 of the wafer unit 11 fixed by the frame holding mechanism 14, the frame holding mechanism 14 is moved along the X-axis direction by the positioning mechanism 30, whereby the wafer unit 11 is positioned above the opening.

[0047] As shown in Figures 1, 2, and 4, a wafer imaging camera 60 is provided on the path along which the frame holding mechanism 14 is moved to above the push-up mechanism 50, as an imaging means for imaging the top surface of the wafer 13 (Figure 4) attached to the annular frame 21 fixed by the frame holding mechanism 14.

[0048] The imaging by the wafer imaging camera 60 may be performed while the wafer is fixed to the frame holding mechanism 14, or may be performed when the wafer is transported by the transport mechanism 20 before being fixed to the frame holding mechanism 14, or when the wafer is placed on the temporary placement mechanism 10. The placement of the wafer imaging camera 60 can also be designed according to an appropriate position corresponding to each timing.

[0049] 1 and 2, the frame holding mechanism 14 positioned above the opening 4b is adjusted in position by a positioning mechanism 30 (FIGS. 1 and 2) to align the position of the chip 23 to be picked up directly above the push-up mechanism 50, as shown in FIG. 5(A). In this embodiment, the chip 23 is moved horizontally within the XY plane by the positioning mechanism 30 (FIGS. 1 and 2), and the relative position of the chip 23 with respect to the push-up mechanism 50 is determined. However, the push-up mechanism 50 may be configured to move horizontally within the XY plane, and the relative positions of the push-up mechanism 50 and the chip 23 may be determined.

[0050] Figure 5(A) is a cross-sectional view showing a wafer unit 11 arranged above a push-up mechanism 50, which, as shown in Figure 5(B), comprises a suction section 52 formed in a hollow cylindrical shape and constituting an outer layer section, and a square pillar-shaped push-up section 54 arranged inside the suction section 52.

[0051] 5(B), a plurality of suction grooves 52b are formed concentrically around the circumferential direction of suction part 52 at the upper end of suction part 52, and the upper end surface of suction part 52 is configured as suction surface 52a. Each of suction grooves 52b is connected to suction source 58, such as an ejector, via a suction passage (not shown) and a valve 56 formed inside thrust-up mechanism 50. Suction part 52 is connected to lifting mechanism 52c, such as a motor, and moves up and down along the Z-axis direction.

[0052] The push-up unit 54 includes a first push-up pin 54a formed in the shape of a rectangular prism and a second push-up pin 54b formed in the shape of a hollow rectangular prism and surrounding the first push-up pin 54a. The first push-up pin 54a and the second push-up pin 54b are connected to lifting mechanisms 55a and 55b, respectively, which are constituted by motors or the like, and move up and down along the Z-axis direction.

[0053] The upper surfaces 57a, 57b of the first push-up pin 54a and the second push-up pin 54b are flat surfaces that together form a single pressing surface 57, which comes into contact with the underside of the tape and pushes up the chip from below, as will be described in detail later.

[0054] Note that, like a push-up portion 54A shown in FIG. 5(C), a configuration may be adopted in which one push-up pin 54c is provided, and the pressing surface 57A may be configured by an upper surface 57c of the push-up pin 54c.

[0055] As shown in FIG. 6A, the area 57M of the pressing surface 57 of the push-up portion 54, i.e., the combined area of ​​the two upper surfaces 57a and 57b, is set smaller than the area 23M (area of ​​the back surface) of the chip 23 to be picked up. In the example of FIG. 6A, the area 57M of the pressing surface 57 is set to be approximately 1 / 25 of the area 23M of the chip 23, but is not limited to this. Note that the smaller the area 57M of the pressing surface 57, the more chip sizes it can accommodate. Furthermore, in this embodiment, the pressing surface 57 formed by the upper surface of the push-up portion 54 is a rectangle similar to the shape of the chip 23, but it may also be a non-similar shape.

[0056] FIG. 6(B) shows the configuration of the push-up portion 54A of FIG. 5(C), in which the area 57AM of the pressing surface 57A formed by the upper surface 57c is set smaller than the area 23M (area of ​​the back surface) of the chip 23 to be picked up. In the example of FIG. 6(B), the area 57AM of the pressing surface 57A is set to be approximately 1 / 25 of the area 23M of the chip 23, but is not limited to this. Note that the smaller the area 57AM of the pressing surface 57A, the more chip sizes can be accommodated. In this embodiment, the pressing surface 57A formed by the upper surface of the push-up portion 54A is a rectangle similar to the shape of the chip 23, but it may also be a non-similar shape.

[0057] Next, the pickup mechanism 70 shown in FIG. 2 will be described. The chip pushed up by the push-up mechanism 50 is picked up by a pickup mechanism 70. The pickup mechanism 70 is equipped with a chip holder 76 (collet) that picks up the chip pushed up by the push-up mechanism 50, and is connected to a chip holder moving mechanism 80 that controls the position of the chip holder 76.

[0058] 7 is a perspective view showing a pickup mechanism 70. The pickup mechanism 70 comprises a movable base 72 connected to a chip holder moving mechanism 80, and a columnar arm 74 arranged along the X-axis direction from the movable base 72 toward the opposite side of the chip holder moving mechanism 80, connecting the chip holder 76 to the chip holder moving mechanism 80. The arm 74 comprises a columnar first support portion 74a connected to the chip holder moving mechanism 80 via the movable base 72, and a second support portion 74b protruding downward from the tip of the first support portion 74a.

[0059] The first support portion 74a and the second support portion 74b are configured to be connectable and detachable to each other. For example, the first support portion 74a and the second support portion 74b are configured to be detachable from each other using a tool changer or the like. The first support portion 74a is configured to move in the X-axis direction by an X-axis direction movement mechanism 74d, thereby allowing the second support portion 74b to move in the X-axis direction. This makes it possible to select the storage position in the X-axis direction when storing the chip in the chip storage device 501 shown in FIG. 1.

[0060] As shown in Figure 7, a chip holder 76 that holds a chip is fixed to the lower end side of the second support part 74b. The lower surface of the chip holder 76 forms a suction surface 76a that suction-holds the chip. The suction surface 76a is connected to a suction source (not shown) via a suction path (not shown) formed inside the chip holder 76. With the chip in contact with the suction surface 76a of the chip holder 76, the chip is suction-held by the chip holder 76 by applying negative pressure from the suction source to the suction surface 76a.

[0061] 2, the pickup mechanism 70 is connected to a chip holder moving mechanism 80. The chip holder moving mechanism 80 includes a Y-axis moving mechanism 82 that moves the pickup mechanism 70 along the Y-axis direction, and a Z-axis moving mechanism 92 that moves the pickup mechanism 70 along the Z-axis direction. The Y-axis moving mechanism 82 and the Z-axis moving mechanism 92 control the positions of the chip holder 76 in the Y-axis and Z-axis directions.

[0062] The Y-axis movement mechanism 82 includes a pair of guide rails 84 arranged along the Y-axis direction. A ball screw 86 is provided between the pair of guide rails 84 and arranged generally parallel to the pair of guide rails 84. A pulse motor 88 that rotates the ball screw 86 is connected to one end of the ball screw 86.

[0063] A moving block 90 is slidably mounted on the pair of guide rails 84. The moving block 90 is also provided with a nut portion (not shown), which is threadedly engaged with a ball screw 86. When the ball screw 86 is rotated by the pulse motor 88, the moving block 90 moves in the Y-axis direction along the pair of guide rails 84.

[0064] 2 and 7, the Z-axis movement mechanism 92 includes a pair of guide rails 94 arranged along the Z-axis direction on the side surfaces of the movement block 90. ​​A ball screw 96 is provided between the pair of guide rails 94 and arranged generally parallel to the pair of guide rails 94. A pulse motor 98 that rotates the ball screw 96 is connected to one end of the ball screw 96.

[0065] 7, a movable base 72 of the pickup mechanism 70 is slidably mounted on a pair of guide rails 94. A nut portion (not shown) is provided on the movable base 72, and this nut portion is threadedly engaged with a ball screw 96. When the ball screw 96 is rotated by a pulse motor 98, the movable base 72 moves in the Z-axis direction along the pair of guide rails 94.

[0066] The pickup mechanism 70 configured as described above picks up the chip 23 pushed up by the push-up mechanism 50. The picked-up chip is transported to the chip observation mechanism 100 or the strength measurement mechanism 200 as appropriate, and is also stored in the chip storage device 501 as appropriate, as shown in FIG.

[0067] Next, an image captured by the chip backside imaging unit 7 (FIGS. 1 and 2) will be described. 8(A) and 8(B), when the chip 23 is pushed up by the push-up mechanism 50, the pushed-up portion 23m corresponding to the push-up portion 54 is peeled off from the tape 19. Furthermore, as the pushed-up portion 23m is peeled off, the surrounding portion 23n of the pushed-up portion 23m is also peeled off. In FIG. 8(A), the surrounding portion 23n is shown as a roughly fan-shaped portion.

[0068] 9 is an example of an image P1 formed by capturing an image of the backside of the chip through the tape after the chip has been pushed up. The image P1 is processed to be a grayscale image, for example, and the peeled portion H1 that has peeled off the tape, i.e., the portion corresponding to the pushed-up portion 23m and the surrounding portion 23n, has a high brightness. On the other hand, the non-peeled portion H2 that has not peeled off the tape 19 has a low brightness.

[0069] As shown in Figure 9, the controller 1 has the following components for detecting the peeled state of the chip: a chip backside imaging unit control unit 101 that controls the operation of the chip backside imaging unit 7; a memory unit 102 that stores the captured image P1; an image processing unit 103 that processes the captured image P1 to identify peeled areas H1 and non-peeled areas H2; a judgment unit 104 that judges whether the chip has been peeled from the tape and can be picked up; a push-up position setting unit 105 that selects the area to be pushed up based on the chip size and the captured image; and a map memory unit 106 that stores the coordinates of the area that has been pushed up until it is judged that peeling has occurred as map data M.

[0070] As shown in FIG. 9, the controller 1 also includes a push-up mechanism control unit 111 that controls the operation of the push-up mechanism 50, a position control unit 112 that controls the positioning mechanism 30 (FIG. 1) that positions the chip at a predetermined position in a horizontal plane, a wafer imaging camera control unit 113 that controls the wafer imaging camera 60 (FIG. 1) that images the front side of the wafer, and a chip size memory unit 114 that stores the size of the chip to be picked up.

[0071] Next, a pickup method using the above configuration will be described below. Figure 10 is a flowchart showing each step of the pickup method described below.

[0072] The following describes the configuration of the push-up unit 54 shown in Figures 5(B) and 6(A), but the same applies to the push-up unit 54A shown in Figures 5(C) and 6(B). Also, various processes such as control of each operation required to carry out the following method and calculation of position coordinates based on captured images are executed by the controller 1 (Figures 1 and 9).

[0073] <Wafer surface imaging step> As shown in FIG. 4, this is a step in which the wafer 13 is imaged from above by the wafer imaging camera 60 to capture an image for identifying the arrangement of each chip 23.

[0074] Based on the captured image, the controller calculates the center position and corner position coordinates of each chip 23. The controller stores in advance the chip size and the center position coordinates of the push-up mechanism 50, and specifies the relative positional relationship between each chip 23 and the push-up mechanism 50 on the horizontal plane.

[0075] <Thrust Step> As shown in Figures 5(A) and 8(B), this is a step in which the chip 23 is positioned relative to the push-up mechanism 50 via the tape 19, and while the back surface of the tape 19 is being sucked by the suction surface 52a, the push-up section 54 pushes up the chip 23 via the tape 19, thereby peeling the chip 23 from the tape 19.

[0076] Specifically, as shown in Fig. 5(A), the controller moves the tip 23 to be pushed up first above the push-up mechanism 50 (initial positioning step). For example, as in the example of Fig. 8(A), the push-up position setting unit 105 (Fig. 9) positions the tip 23 based on the rectangular shape and size of the tip 23 so that the area 23m to be pushed up by the pressing surface 57 is positioned inside one of its corners. Note that the present invention can also be implemented when the tip 23 is not rectangular.

[0077] The positioning of the chip 23 is performed by controlling the positioning mechanism 30 (FIG. 1) by the position control section 112 (FIG. 9) of the controller to move the frame holding mechanism 14 (wafer unit 11 (FIG. 1)).

[0078] Next, as shown in FIG. 8(B), the suction surface 52a of the suction unit 52 is raised until it contacts the tape 19, and suction is initiated to hold the tape 19 by the suction surface 52a. Next, the first push-up pins 54a and the second push-up pins 54b are pushed up, thereby peeling the pushed-up portion 23m of the chip 23 from the tape 19. In the example of FIG. 8(B), the first push-up pins 54a are pushed up higher than the second push-up pins 54b (first push-up step). As the pushed-up portion 23m is pushed up, the surrounding portion 23n is also peeled off at the same time.

[0079] <Imaging steps> As shown in FIG. 11, this is a step in which the back surface side of the chip 23 is imaged through the tape 19 to form an imaged image P1 (FIG. 9).

[0080] Specifically, the controller moves the chip 23 pushed up in the first pushing-up step above the chip backside imaging unit 7, and causes the chip backside imaging unit 7 to image the chip 23 through the tape 19 and store the captured image P1 (FIG. 9). As shown in FIG. 9, the controller processes the captured image P1 to distinguish between peeled areas H1 and non-peeled areas H2 (first imaging step).

[0081] <Determination step> As shown in FIG. 9, this is a step in which it is determined whether or not the chip 23 has peeled off from the tape 19 based on the captured image P1.

[0082] Specifically, if the peeled area H1 identified in the first imaging step occupies a wide area of ​​the chip 23, the controller determines that the chip 23 has peeled off from the tape 19. On the other hand, if the peeled area H1 identified in the first imaging step occupies only a narrow area of ​​the chip 23 and many non-peeled areas H2 remain, the controller determines that the chip 23 has not peeled off from the tape 19.

[0083] 11, many non-peeled areas H2 remain, and it is determined that no peeling has occurred. As a criterion for determination, for example, if peeled areas H1 occupy 90% or more of the area of ​​the back surface of chip 23, it can be determined that peeling has occurred. The determination condition (threshold value) that serves as the criterion for determining whether or not peeling has occurred is set appropriately depending on the strength and thickness of chip 23 and the type of tape 19.

[0084] <Additional thrust step> In this step, if it is determined in the determination step that the chip 23 has not been peeled off from the tape 19, an additional push-up is performed on the non-peeled portion H2.

[0085] For example, as shown in FIG. 12(A), when a non-peeled portion H2 remains, the non-peeled portion H2 is subjected to thrusting in the same manner as in the first thrusting step.

[0086] Here, the controller 1 selects a location to be pushed up in the non-peeled location H2 by the push-up position setting unit 105 (Fig. 9). For example, as shown in Fig. 12(A), if the chip 23 is rectangular and the initial push-up step has been performed on a pushed-up location 23m inside one of its corners, the push-up position setting unit 105 (Fig. 9) selects a location inside another corner (the corner diagonally opposite the peeled location H1) in the non-peeled location H2 as an additional pushed-up location 23p, as shown in Fig. 12(B).

[0087] Then, as shown in Fig. 12(B), thrusting is performed on the additional thrusted portion 23p. Next, the imaging step is performed in the same manner as above to obtain a captured image P2 as shown in Fig. 12(B), and the determination step is performed in the same manner as above.

[0088] Similarly, the pushing-up step, the imaging step, the judging step, and the additional pushing-up step are repeated until it is judged in the judging step that the chip 23 has peeled off from the tape 19. In other words, the pushing-up of the non-peeled portion H2 is repeated sequentially.

[0089] In the example of FIGS. 12(A) to 12(D), a total of four push-up steps are performed, and all areas of the chip become peeled areas H1, with no non-peeled areas H2 remaining.

[0090] In the example of FIGS. 13(A) to 13(H), a total of eight push-up steps are performed, and most of the chip area becomes peeled areas H1, except for some non-peeled areas H2 near the center.

[0091] 13, it is preferable to reduce the non-peeled areas H2 by first performing the push-up on the corners of the chip or on the side closer to the periphery. This is because the corners of the chip and the side closer to the periphery are particularly difficult to peel, and by leaving areas that are easy to peel, the number of push-up steps can be minimized.

[0092] Also, unlike in FIG. 12 and FIG. 13, if it is determined that the material has been peeled off after only the first push-up step, the process proceeds to the next pick-up step without performing an additional push-up step.

[0093] 9, the map storage unit 106 (FIG. 9) of the controller stores map data M including the coordinates (coordinates within the chip) of the pushed-up locations 23p (there may be multiple locations) selected before it is determined that the chip has been peeled. In the example of FIG. 9, the pushed-up locations 23p that were pushed up in the first push-up step are shown in black. This makes it possible to push up the same locations as the pushed-up locations 23p included in the map data M when the next chip to be picked up is pushed up.

[0094] In the above example, the pushing-up step and the imaging step were repeated alternately to determine peeling, but it is also possible to perform the pushing-up step at multiple locations and then the imaging step, and obtain an image P1 after multiple locations have been pushed up to make the determination.

[0095] In addition, the radius of the peeling point H1 identified in the first push-up step may be determined, and the coordinates and number of push-up points 23m required to peel the entire chip may be automatically calculated or determined by the operator.

[0096] <Pickup step> As shown in FIG. 14, this is a step in which, when it is determined that the chip 23 has peeled off from the tape 19, the front surface side of the chip 23 is held by the chip holder 76 and picked up.

[0097] Specifically, the chip holder moving mechanism 80 (Figure 2) positions the chip holder 76 of the pickup mechanism 70 above the chip 23, and the suction surface 76a of the chip holder 76 suction-holds the chip 23, thereby separating the chip 23 from the tape 19 and picking it up.

[0098] In addition, if the chip holder 76 of the pickup mechanism 70 is configured not to move horizontally, the position of the chip 23 is aligned with the position of the chip holder 76 by first releasing the push-up force and then moving the frame holding mechanism 14 (Figure 1).

[0099] Furthermore, the pickup step may be performed with the push-up mechanism 50 (push-up portion 54) pushing up the chip 23 as shown in FIG. 14, or may be performed with the push-up mechanism 50 (push-up portion 54) lowered.

[0100] Here, if the pickup of the chip 23 fails, that is, if the chip 23 does not separate from the tape 19 but remains stuck to it, the suction surface 76a of the chip holder 76 will not be blocked by the chip 23. This situation can be detected, for example, by monitoring the suction pressure of the suction path leading to the suction surface 76a. If this situation is detected, the pickup may be stopped and the judgment conditions may be changed, and the process may be started again from the pushing-up step.

[0101] <Separate tip push-up step> This is a step of performing a push-up on another chip at the stored push-up position.

[0102] As described above, the map storage unit 106 (FIG. 9) of the controller stores map data M of the pushed-up location 23p (there may be multiple locations) selected before it is determined that the chip has been peeled. This map data M is used to push up the same location of another chip, for example, a chip next to the chip that was initially picked up.

[0103] In this way, by acquiring map data M of the pushed-up portion 23p for one chip and using the map data M when pushing up another chip, it becomes possible to immediately push up the other chip without performing the imaging step or the judgment step. In other words, the imaging step and the judgment step can be omitted, thereby improving throughput.

[0104] The other chips may be chips separated from the same wafer, or chips separated from different wafers of the same type (chips of the same type). In other words, when picking up multiple chips from multiple wafers of the same type, map data M of the push-up location is obtained when peeling off the first chip from the first wafer, so that the same location can be pushed up in other chips included in the same wafer, and even in other chips included in different wafers.

[0105] <Separate chip pick-up step> The above-described pick-up step is performed for another chip. After the pick-up step, another chip push-up step is performed to pick up another chip.

[0106] When a pickup failure occurs during pickup, the recurrence of the pickup failure can be prevented by changing the conditions for judgment in the same manner as described above.

[0107] As described above, according to the present invention, the chip is peeled from the tape by being pushed up multiple times by a push-up part having a pressing surface smaller than the chip to be picked up, so that it is possible to handle the pickup of chips of different sizes. Furthermore, since the chip is picked up after determining whether it has peeled off based on an image of the back side of the pushed-up chip, it is possible to prevent the occurrence of chip damage caused by picking up a chip without peeling off.

[0108] Furthermore, by performing additional pushing up when it is determined that the chip has not been peeled off, the number of pushing ups required until peeling can be minimized, and problems such as chip breakage due to the load being placed on the chip can be prevented.

[0109] Furthermore, by using the map data M of the push-up location when it is determined that the chip has been peeled, the same push-up method can be used to peel other chips from the next time onwards. This makes it possible to omit the imaging step and the determination step, thereby improving the throughput of the pickup.

[0110] In addition to the above example, after performing push-up for one chip and acquiring map data M, push-up for all other chips may be performed by referring to map data M, and if a determination step is performed for each chip and peeling is not found, an additional push-up step may be performed as appropriate to peel the chips. After peeling is confirmed for all chips, the pick-up step is executed for all chips. [Explanation of symbols]

[0111] 1 Controller 2 Pickup device 7 Chip backside imaging unit 10 Mechanism 11 Wafer Unit 13 wafers 13a surface 13b Back side 19 Tape 23 chips 23M area 23m Pushed up point 23n surrounding areas 23p Additional thrust points 24 devices 30 Positioning mechanism 50 Push-up mechanism 52 Suction part 54 Push-up part 57 Pressing surface 60 wafer imaging camera 70 Pickup mechanism 100 Tip observation mechanism 101 Chip backside imaging unit control section 102 Storage section 103 Image processing section 104 Judgment section 105 Push-up position setting section 106 Map memory section 111 Mechanism control unit 112 Position control section 113 Wafer imaging camera control unit H1 Peeling area H2 Non-peeling area M Map Data P1 Captured image P2 Captured image

Claims

1. A pickup method for picking up a chip attached to a tape from the tape, comprising the steps of: the chip is positioned via the tape relative to a push-up mechanism including a suction section having a suction surface for suction-holding the back surface of the tape, and a push-up section disposed inside the suction surface and having a pressing surface at its tip that is smaller than the chip to be picked up, and which can be raised and lowered; a push-up step of pushing up the chip through the tape with the push-up section while sucking the back surface of the tape with the suction surface, thereby peeling the chip from the tape; an imaging step of imaging the back side of the chip through the tape to form an image; a determining step of determining whether the chip has peeled off from the tape based on the captured image; a pick-up step of picking up the chip by holding the front surface side of the chip with a chip holder when it is determined that the chip has peeled off from the tape; If it is determined in the determining step that the chip has not been peeled off from the tape, An additional pushing step of additionally pushing up the non-peeled portion. Pickup method.

2. In the determining step, a pushed-up point on the chip that has been pushed up by the push-up mechanism until it is determined that the chip has peeled off the tape is stored; When picking up a chip of the same type as the chip attached to the tape, the step of pushing up is performed for the stored pushed-up location without performing the imaging step and the determining step.

2. The pickup method according to claim 1.

3. A pickup method for picking up a chip attached to a tape from the tape, comprising: the chip is positioned via the tape relative to a push-up mechanism including a suction section having a suction surface for suction-holding the back surface of the tape, and a push-up section disposed inside the suction surface and having a pressing surface at its tip that is smaller than the chip to be picked up, and which can be raised and lowered; a push-up step of pushing up the chip through the tape with the push-up section while sucking the back surface of the tape with the suction surface, thereby peeling the chip from the tape; an imaging step of imaging the back side of the chip through the tape to form an image; a determining step of determining whether the chip has peeled off from the tape based on the captured image; a pick-up step of picking up the chip by holding the front surface side of the chip with a chip holder when it is determined that the chip has peeled off from the tape, In the determining step, a pushed-up point on the chip that has been pushed up by the push-up mechanism until it is determined that the chip has peeled off the tape is stored; When picking up a chip of the same type as the chip stuck to the tape, the pick-up method performs the pushing-up step for the stored pushing-up location without performing the imaging step and the judging step.

4. A pickup device that picks up chips attached to a tape from the tape, comprising: a push-up mechanism including a suction section having a suction surface for suction-holding the back surface of the tape, and a push-up section that is arranged inside the suction surface and has a pressing surface at its tip that is smaller than the chip to be picked up and can be raised and lowered; a positioning mechanism for positioning the chip relative to the push-up mechanism via the tape; a chip backside imaging unit that images the backside of the chip through the tape to form an image; a controller that determines whether the chip has peeled off from the tape based on the captured image; a pickup mechanism that picks up the chip by holding the front surface side of the chip; Equipped with the controller picks up the chip when it determines that the chip has been peeled off from the tape; The controller a chip backside imaging unit control unit for controlling the operation of the chip backside imaging unit; a storage unit that stores the captured image; an image processing unit that processes the captured image to distinguish between peeled and non-peeled areas; a determination unit that determines whether the chip can be peeled off from the tape and picked up; a push-up position setting unit that selects a position to be pushed up in the non-peeled portion; and Repeat pushing up the non-peeled areas until it is determined that the peeling has occurred. Pickup device.

5. The method further includes a map storage unit that stores, as map data, coordinates of the points that have been pushed up until it is determined that peeling has occurred, When pushing up another chip, the same pushing up location as the pushing up location included in the map data is pushed up.

5. The pickup device according to claim 4.

6. A pickup device for picking up chips attached to a tape from the tape, comprising: a push-up mechanism including a suction section having a suction surface for suction-holding the back surface of the tape, and a push-up section that is arranged inside the suction surface and has a pressing surface at its tip that is smaller than the chip to be picked up and can be raised and lowered; a positioning mechanism for positioning the chip relative to the push-up mechanism via the tape; a chip backside imaging unit that images the backside of the chip through the tape to form an image; a controller that determines whether the chip has peeled off from the tape based on the captured image; a pickup mechanism that picks up the chip by holding the front surface side of the chip; Equipped with the controller picks up the chip when it determines that the chip has been peeled off from the tape; The method further includes a map storage unit that stores, as map data, coordinates of the points that have been pushed up until it is determined that peeling has occurred, When pushing up another chip, the same pushing up location as the pushing up location included in the map data is pushed up. Pickup device.

Images