Attachment method

Abstract

To paste a tape to a ring frame so that the tape is difficult to peel off from the ring frame.SOLUTION: A pasting method for pasting a tape having a workpiece pasted thereto to a ring frame includes an expanding step for expanding the tape in all directions, an arrangement step for arranging a ring frame on the tape which has been expanded, a first pasting step of pressing the tape against one surface of the ring frame along an inner circumference of an opening portion to paste the tape onto a first annular area of the one surface, a relaxing step of relaxing stretching of the expanded tape, a second pasting step of pasting the tape onto a second annular area located outside the first annular area on one surface, and a separation step of cutting the tape into a circular shape along the inner circumference of the opening portion with a cutting blade being cut into a predetermined position of the tape located outside the first annular area, thereby separating the tape into a circular area and an outer peripheral area.SELECTED DRAWING: Figure 7

Description

Technical Field

[0001] The present invention relates to an attaching method for attaching a tape with a work attached thereto to a ring frame.

Background Art

[0002] After forming a fragile region (so-called, modified layer) inside a work such as a semiconductor wafer having a plurality of devices formed on the front surface side by irradiating a laser beam thereto, a rectangular adhesive tape (hereinafter, tape) attached to the back surface side of the work is expanded in all directions, thereby a method of dividing the work into a plurality of device chips has been put into practical use.

[0003] When expanding the tape, an expanding device is used. For example, when the expanding device forms substantially the same interval between a plurality of device chips having different lengths in the vertical and horizontal directions, the tape is expanded such that the expansion amounts in the vertical direction and the horizontal direction of the tape are different (for example, see Patent Document 1). After the expansion of the tape, by attaching a ring frame to the outside of the work, the interval between the device chips is maintained even after the expansion of the tape by the expanding device is released.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, when the tape is expanded, the adhesive layer of the tape is also expanded in all directions together with the base material layer of the tape, so that the thickness of the adhesive layer becomes thin. Therefore, there has been a problem that the adhesive force to the ring frame decreases with the passage of time, and finally the tape peels off from the ring frame.

[0006] The present invention has been made in view of such problems, and an object thereof is to attach a tape to a ring frame so that the tape is difficult to peel off from the ring frame.

Means for Solving the Problems

[0007] According to one aspect of the present invention, there is provided a pasting method for pasting a tape to which a workpiece is pasted onto a ring frame, Attach the tape to the back surface of the workpiece with the protective tape attached to the front surface, and then clamp the four corners of the tape with a clamping mechanism to eliminate the slack of the tape, and then peel off the protective tape in a state where the slack of the tape is eliminated. Then, after clamping the four sides of the tape with the first, second, third, and fourth clamping units, release the clamping of the tape by the clamping mechanism, and transfer the workpiece and the tape from the clamping mechanism to the first, second, third, and fourth clamping units. A transfer step, and after the transfer step, with the first, second, third, and fourth clamping units an expanding step of expanding the tape in all directions; an arranging step of arranging the ring frame on the tape in a state where the tape is expanded so that the workpiece is positioned at the opening of the ring frame; after the arranging step, a first pasting step of pasting the tape to a first annular region on one surface by pressing the tape against one surface of the ring frame along the inner peripheral circle of the opening; a relaxing step of relaxing the extension of the expanded tape after the first pasting step; after the relaxing step, a second pasting step of pasting the tape to a second annular region located outside the first annular region on one surface of the ring frame by pressing the tape against one surface of the ring frame along the inner peripheral circle of the opening; and a separating step of separating the tape into a circular region integrated with the workpiece and the ring frame and an outer peripheral region located outside the circular region by cutting the tape circularly along the inner peripheral circle of the opening with a cutting blade cut into a predetermined position of the tape located outside the first annular region after the second pasting step.

[0008] Preferably, in the separating step, the tape is cut circularly with the cutting blade cut into the outer peripheral edge of the corresponding region of the tape corresponding to the second annular region. Also, preferably, in the expanding step, the tape is expanded in all directions by the first, second, third, and fourth clamping units. In the relaxing step, each of the first, second, third, and fourth clamping units that clamp the tape is moved in a direction opposite to the direction of movement in the expanding step by a distance shorter than the moving distance in the expanding step, thereby relaxing the stretching of the expanded tape.

Advantages of the Invention

[0009] In the pasting method according to one aspect of the present invention, after the first pasting step of pasting a tape on the first annular region on one surface of the ring frame, a relaxation step of relaxing the extension of the extended tape is performed. Thereby, the extension of the tape is maintained inside the first annular region, while the extension of the tape is relaxed outside the first annular region.

[0010] Then, after the relaxation step, a second pasting step of pasting the tape on the second annular region located outside the first annular region is performed. The thickness of the adhesive layer of the tape pasted on the second annular region is thicker than the region corresponding to the first annular region, so that a decrease in the adhesive force of the tape over time can be suppressed. Therefore, the adhesive force is stably exhibited, and it becomes difficult for the tape to peel off from the ring frame.

Brief Description of the Drawings

[0011]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Embodiments for Carrying Out the Invention

[0012] Referring to the accompanying drawings, an embodiment according to one aspect of the present invention will be described. First, the expansion device 2 used in the pasting method of the present embodiment will be described. FIG. 1 is a perspective view of the expansion device 2. The X-axis direction, Y-axis direction, and Z-axis direction (height direction) shown in FIG. 1 are orthogonal to each other.

[0013] The expansion device 2 has a base 4 that supports a plurality of components. A rectangular opening 4a is provided at the center of the base 4. Above the opening 4a, a disc-shaped chuck table (holding table) 6 is arranged. The chuck table 6 has a metal frame.

[0014] A disc-shaped recess is formed in the frame, and a disc-shaped porous ceramic is fixed in this recess. A predetermined flow path (not shown) is formed in the frame, and a suction source (not shown) such as an ejector is connected to this flow path.

[0015] When the suction source is operated, a negative pressure is transmitted to the upper surface of the porous ceramic. The upper surfaces of the porous ceramic and the frame function as holding surfaces for sucking and holding the tape 15 described later.

[0016] Four clamp mechanisms (not shown) are provided on the side of the chuck table 6. The four clamp mechanisms are arranged at substantially equal intervals along the circumferential direction of the chuck table 6, and pull the four corners of the tape 15 to eliminate the slack of the tape 15.

[0017] A columnar lifting unit 8 that can move up and down in the vertical direction is connected to the lower part of the chuck table 6. The lifting unit 8 moves the chuck table 6 up and down so as to pass through the opening 4a.

[0018] A disc-shaped support plate (not shown) having a larger diameter than the lifting unit 8 is provided at the lower part of the lifting unit 8. The support plate is arranged concentrically with the lifting unit 8. A rotational drive source (not shown) such as a motor is provided at the lower part of this support plate.

[0019] The rotational drive source is supported by a moving plate (not shown) disposed below the base 4. The moving plate is slidably attached to a pair of guide rails (not shown) arranged along a predetermined direction. A nut portion (not shown) is provided on the lower surface side of the moving plate.

[0020] A ball screw (not shown) arranged substantially parallel to the guide rail is rotatably connected to the nut portion. A motor (not shown) is connected to one end of the ball screw. The moving plate, the pair of guide rails, the ball screw, the motor, etc. constitute a moving mechanism for moving the chuck table 6 in the horizontal direction (for example, the X-axis direction).

[0021] A first roller 10 (see FIG. 5(A)), a second roller 12 (see FIG. 7(A)), and a cutting blade 14 (see FIG. 8) are provided on the side portion of the chuck table 6 in a manner supported by the support plate.

[0022] The first roller 10 is provided at the upper end of the air cylinder 10a (see FIG. 5(A)). The first roller 10 has a relatively small width (the length of the cylinder). The first roller 10 has a width corresponding to about 1 / 9 to 1 / 7 of the radial width of the ring frame 17 (that is, the difference between the outer diameter and the inner diameter), for example.

[0023] Similarly, the second roller 12 is provided at the upper end of the air cylinder 12a (see FIG. 7(A)). The second roller 12 has a relatively large width. The second roller 12 has a width corresponding to about 6 / 7 to 8 / 9 of the radial width of the ring frame 17, for example. Also, the cutting blade 14 is provided at the upper end of the air cylinder 14a (see FIG. 8).

[0024] The air cylinders 10a, 12a, 14a are arranged on the outer peripheral portion of the support plate. If the rotational drive source is operated, the first roller 10, the second roller 12, and the cutting blade 14 rotate around the lifting unit 8 together with the chuck table 6.

[0025] Above the base 4, at one end in the X-axis direction, a first clamping unit 20a is provided. The first clamping unit 20a has a moving plate 22. The moving plate 22 has a protruding portion 22a that is slidably fitted into a guide groove 4b provided in the base 4.

[0026] The moving plate 22 is provided with a through-hole through which a ball screw 24 passes, and this ball screw 24 is rotatably connected to a nut portion (not shown) provided on the lower surface of the moving plate 22.

[0027] A pulse motor 26 is provided at one end of the ball screw 24. If the pulse motor 26 is rotated in a predetermined direction, the moving plate 22 approaches the opening 4a, and if the pulse motor 26 is rotated in the opposite direction of the predetermined direction, the moving plate 22 moves away from the opening 4a.

[0028] A support column 28 extending in the Z-axis direction is provided at one end of the moving plate 22. A convex portion 30 is formed on one side surface of the support column 28 on the opening 4a side. The concave portions of the upper arm 32 and the lower arm 42 are slidably fitted into the convex portion 30.

[0029] A nut portion 34 is provided at the base end of the upper arm 32. The nut portion 34 passes through an opening provided in the convex portion 30 and is located on the other surface side of the support column 28. A ball screw 36 arranged substantially parallel to the Z-axis direction is rotatably connected to the nut portion 34.

[0030] A pulse motor 38 is connected to the upper end of the ball screw 36. If the pulse motor 38 is rotated in a predetermined direction, the upper arm 32 moves downward, and if the pulse motor 38 is rotated in the opposite direction of the predetermined direction, the upper arm 32 moves upward.

[0031] At the tip of the upper arm 32, a rectangular parallelepiped-shaped upper clamping part 32a having a long part in a direction orthogonal to the longitudinal direction of the upper arm 32 in the horizontal direction is provided. A plurality of columnar rollers (not shown) are provided along the longitudinal direction of the upper clamping part 32a. The rotation axis of each roller is arranged substantially parallel to the longitudinal direction of the upper arm 32.

[0032] At the base end of the lower arm 42, a nut part 44 is provided. The nut part 44 passes through the opening provided in the convex part 30 and is located on the other surface side of the support column 28. A ball screw 46 arranged substantially parallel to the Z-axis direction is rotatably connected to the nut part 34.

[0033] A pulse motor 48 is connected to the lower end of the ball screw 46. If the pulse motor 48 is rotated in a predetermined direction, the lower arm 42 moves upward, and if the pulse motor 48 is rotated in the opposite direction of the predetermined direction, the lower arm 42 moves downward.

[0034] At the tip of the lower arm 42, a rectangular parallelepiped-shaped lower clamping part 42a having a long part in a direction orthogonal to the longitudinal direction of the lower arm 42 in the horizontal direction is provided. A plurality of columnar rollers 42b are provided along the longitudinal direction of the lower clamping part 42a. The rotation axis of each roller 42b is arranged substantially parallel to the long part of the lower arm 42.

[0035] On the opposite side of the first clamping unit 20a with respect to the opening 4a, a second clamping unit 20b is provided. The structure of the second clamping unit 20b is substantially the same as that of the first clamping unit 20a. The first clamping unit 20a and the second clamping unit 20b have the function of expanding the tape 15 in the X-axis direction.

[0036] Similarly, a third clamping unit 20c and a fourth clamping unit 20d are provided so as to sandwich the opening 4a in the Y-axis direction. The third clamping unit 20c and the fourth clamping unit 20d each have substantially the same structure as the first clamping unit 20a and have the function of expanding the tape 15 in the Y-axis direction.

[0037] Next, with reference to FIGS. 2 to 8, a pasting method for pasting the tape 15 (see FIG. 3 etc.) to which the work 11 is pasted onto the ring frame 17 (see FIG. 4 etc.) will be described. FIG. 2 is a flowchart of the pasting method.

[0038] The work 11 of the present embodiment is a semiconductor wafer on which a device such as an IC (Integrated Circuit) is formed on the front surface side. However, a modified layer is formed on the work 11 along the planned division line, and then the back surface side is ground.

[0039] Specifically, with a protective tape (not shown) pasted on the front surface side of the work 11, the formation of the modified layer and the grinding of the back surface side are sequentially performed on the work 11, so that cracks reach the front and back surfaces of the work 11 starting from the modified layer.

[0040] After grinding 、 A resin tape 15 is pasted on the back surface side of the work 11. The tape 15 has a laminated structure of a base material layer and an adhesive layer (paste layer) provided on one surface of the base material layer.

[0041] The base material layer is made of a resin such as polyolefin, polyvinyl chloride, polyethylene terephthalate, etc., and the adhesive layer is formed of an adhesive such as acrylic, silicone, rubber, or acrylic.

[0042] After the tape 15 is pasted, the four corners of the tape 15 are clamped by the clamp mechanism provided on the four sides of the chuck table 6 to eliminate the slack of the tape 15, and the protective tape is peeled off from the front surface side of the work 11 by a peeling mechanism (not shown).

[0043] Thereafter, the chuck table 6 is moved downward below the opening 4a by the moving mechanism, and further, the chuck table 6 is raised to substantially the same height as the first clamping unit 20a etc. by the lifting unit 8.

[0044] Next, after the four sides of the tape 15 are clamped by the first clamping unit 20a, the second clamping unit 20b, the third clamping unit 20c, and the fourth clamping unit 20d, the clamping mechanism is released. Thereby, the laminate of the workpiece 11 and the tape 15 is delivered to the expanding device 2.

[0045] In this state, first, the first clamping unit 20a and the second clamping unit 20b are moved along the X-axis direction by a predetermined distance (for example, 10 mm) so as to move away from the opening 4a. Next, the third clamping unit 20c and the fourth clamping unit 20d are moved along the Y-axis direction by a predetermined distance (for example, 10 mm) so as to move away from the opening 4a.

[0046] In this way, the tape 15 is expanded in all directions (expansion step S10). FIG. 3 is a diagram showing the expansion step S10. In the drawings after FIG. 3, the third clamping unit 20c and the fourth clamping unit 20d are omitted.

[0047] Incidentally, in the expansion step S10, after expanding the tape 15 along the Y-axis direction, the tape 15 may be expanded along the X-axis direction. Further, the expansion amount of the tape 15 in the X-axis direction and the expansion amount of the tape 15 in the Y-axis direction can be appropriately adjusted according to the shape of the device chip 13.

[0048] After the expansion step S10, while maintaining the expanded state of the tape 15, the ring frame 17 is disposed on the adhesive layer side of the tape 15 (disposal step S20). FIG. 4 is a diagram showing the disposal step S20.

[0049] In the present embodiment, the upper surface 17a side of the metal ring frame 17 is sucked and held by the disk-shaped suction unit 50 and conveyed, and the ring frame 17 is disposed on the tape 15 so that the workpiece 11 is positioned at the opening 17b of the ring frame 17.

[0050] However, in the placement step S20, it is preferable to separate the ring frame 17 from the tape 15 by a minute distance (several millimeters; for example, from 1 mm to 3 mm). Thereby, in the relaxation step S40 described later, the tape 15 can smoothly contract together with its adhesive layer.

[0051] After the placement step S20, as shown in FIG. 5(A), while maintaining the tape 15 in the extended state, the first roller 10 is raised above the chuck table 6. At this time, the first roller 10 presses a part of the lower surface (one surface) 17c of the ring frame 17 near the inner peripheral circle of the opening 17b.

[0052] In this state, by rotating the support column 16, the tape 15 is pressed by the first roller 10 along the inner peripheral circle of the opening 17b, and the first annular region 17c 1 on the lower surface 17c located near the inner peripheral circle of the opening 17b is attached to the tape 15 (the first attachment step S30).

[0053] FIG. 5(A) is a diagram showing the first attachment step S30. The first annular region 17c 1 is set in the range from the inner peripheral circle of the opening 17b to about 1 / 9 to 1 / 7 of the width of the ring frame 17. For example, the first annular region 17c 1 is a region having a width of about 2 mm to 3 mm from the inner peripheral circle of the opening 17b.

[0054] By the first attachment step S30, the workpiece 11, the tape 15, and the ring frame 17 are integrated to form the workpiece unit 19. FIG. 5(B) is a top view of the workpiece unit 19. In FIG. 5(B), the outer peripheral edge of the first annular region 17c 1 is indicated by a broken line.

[0055] However, in the first annular region 17c 1 , since the tape 15 with the adhesive layer also extended together with the base material layer is attached, over time, the adhesive force to the ring frame 17 decreases, and there is a risk that the tape 15 may peel off from the ring frame 17.

[0056] Therefore, in this embodiment, after the first pasting step S30, the extension (i.e., tension) of the tape 15 is relaxed to contract the tape 15 to some extent (relaxing step S40). FIG. 6 is a diagram showing the relaxing step S40.

[0057] In the relaxing step S40, each of the first clamping unit 20a to the fourth clamping unit 20d is moved by approximately half of the moving distance in the expanding step S10 (for example, 5 mm) so as to approach the opening 4a.

[0058] After the relaxing step S40, the second roller 12 is used to paste the relaxed region onto the lower surface 17c of the ring frame 17 (second pasting step S50). FIG. 7(A) is a diagram showing the second pasting step S50.

[0059] In the second pasting step S50, the first roller 10 is lowered. Instead, the second roller 12 having a larger width than the first roller 10 is raised above the chuck table 6, and the region outside the first annular region 17c 1 is pressed by the second roller 12.

[0060] By rotating the support column 16 with the second roller 12 pressed against the tape 15, the tape 15 is pressed by the second roller 12 along the inner circumferential circle of the opening 17b. Thereby, the tape 15 is pasted onto the second annular region 17c 1 located outside the first annular region 17c 2 of the ring frame 17.

[0061] Note that in the second pasting step S50, the second roller 12 may press the entire lower surface 17c, or may press only the region outside the first annular region 17c 1 FIG. 7(B) is a top view of the work unit 19 after the second pasting step S50. In FIG. 7(B), the outer peripheral edge of the second annular region 17c 2 is shown by a broken line.

[0062] The second annular region 17c 2 In the corresponding region 15a of the tape 15 attached to the first annular region 17c (see FIG. 7(A)), since the adhesive layer is thicker than the region of the tape 15 corresponding to the first annular region 17c 1 it is possible to suppress a decrease in the adhesive force of the tape 15 over time. Therefore, the adhesive force of the tape 15 is stably exhibited, and the tape 15 is less likely to be peeled off from the ring frame 17.

[0063] After the second attachment step S50, the tape 15 is cut into a circular shape and separated into a circular region 15b and an outer peripheral region 15c located outside the circular region 15b (separation step S60). FIG. 8 is a diagram showing the separation step S60.

[0064] In the separation step S60, the second roller 12 is lowered, and instead, the cutting blade 14 is raised above the chuck table 6. Then, the cutting blade 14 is cut into a predetermined position of the tape 15 located outside the first annular region 17c 1 and the support column 16 is rotated.

[0065] In the present embodiment, with the cutting blade 14 cut into the outer peripheral edge of the corresponding region 15a of the tape 15, the support column 16 is rotated, and the tape 15 is cut into a circular shape along the inner peripheral circle of the opening 17b. Thereby, the tape 15 is separated into a circular region 15b and an outer peripheral region 15c.

[0066] By cutting the tape 15 with the outer peripheral edge of the corresponding region 15a as a boundary, substantially all of the corresponding region 15a of the tape 15 attached to the second annular region 17c 2 can be left. Therefore, for example, compared with the case where the tape 15 is cut at a position approximately halfway in the width direction of the second annular region 17c 2 the tape 15 is less likely to be peeled off from the ring frame 17.

[0067] After the separation step S60, the work unit 19 in which the work 11 is supported by the ring frame 17 through the circular region 15b of the tape 15 is conveyed to another processing region by the suction unit 50, and the processing of the next step is performed.

[0068] In this embodiment, the adhesive layer of the corresponding region 15a of the tape 15 corresponding to the second annular region 17c 2 is thicker than the adhesive layer of the region of the tape 15 corresponding to the first annular region 17c 1 Therefore, a decrease in the adhesive force of the tape 15 over time can be suppressed. Therefore, the adhesive force of the tape 15 is stably exhibited, and the tape 15 is less likely to be peeled off from the ring frame 17.

[0069] In addition, the structure, method, etc. according to the above embodiment can be appropriately changed and implemented as long as they do not deviate from the scope of the object of the present invention. For example, as the cutting blade 14, a cutting blade of a rotary cutter can also be used.

[0070] Further, the outer diameter of the range of the lower surface 17c to which the tape 15 is attached in the second pasting step S50 can be extended to a position corresponding to the straight portion of the outer peripheral portion of the ring frame 17. In this way, the larger the diameter of the second annular region 17c 2 is, the more the adhesive force of the tape 15 can be ensured.

Explanation of reference numerals

[0071] 2: Expansion device, 4: Base, 4a: Opening, 4b: Guide groove 6: Chuck table (holding table), 8: Lifting unit 10: First roller, 12: Second roller, 14: Cutting blade 10a, 12a, 14a: Air cylinder, 16: Support column 11: Work, 13: Device chip 15: Tape, 15a: Corresponding region, 15b: Circular region, 15c: Outer peripheral region 17: Ring frame, 17a: Upper surface, 17b: Opening 17c: Lower surface (one surface), 17c 1 : First annular region, 17c2 : Second annular region 19: Work unit 20a: First clamping unit, 20b: Second clamping unit 20c: Third clamping unit, 20d: Fourth clamping unit 22: Moving plate, 22a: Protrusion 24: Ball screw, 26: Pulse motor, 28: Support pillar, 30: Convex part 32: Upper arm, 32a: Upper clamping part 34: Nut part, 36: Ball screw, 38: Pulse motor 42: Lower arm, 42a: Lower clamping part, 42b: Roller 44: Nut part, 46: Ball screw, 48: Pulse motor, 50: Suction unit

Claims

1. A pasting method for pasting a tape with a workpiece attached thereto onto a ring frame, comprising: pasting the tape on the back surface of the workpiece with a protective tape pasted on the surface thereof, then peeling off the protective tape in a state where the slack of the tape is eliminated by clamping the four corners of the tape with a clamping mechanism, and then, after clamping the four sides of the tape with first, second, third, and fourth clamping units, releasing the clamping of the tape by the clamping mechanism to transfer the workpiece and the tape from the clamping mechanism to the first, second, third, and fourth clamping units; an expanding step of expanding the tape in four directions with the first, second, third, and fourth clamping units after the transferring step; an arranging step of arranging the ring frame on the tape so that the workpiece is positioned at the opening of the ring frame in a state where the tape is expanded; a first pasting step of pasting the tape on a first annular region of one surface by pressing the tape against one surface of the ring frame along the inner peripheral circle of the opening after the arranging step; a relaxing step of relaxing the extension of the expanded tape after the first pasting step; a second pasting step of pasting the tape on a second annular region located outside the first annular region of one surface by pressing the tape against one surface of the ring frame along the inner peripheral circle of the opening after the relaxing step; a separating step of separating the tape into a circular region integrated with the workpiece and the ring frame and an outer peripheral region located outside the circular region by cutting the tape into a circle along the inner peripheral circle of the opening with a cutting blade cutting into a predetermined position of the tape located outside the first annular region after the second pasting step; The pasting method is characterized by comprising the above steps.

2. The pasting method according to claim 1, wherein in the separating step, the tape is cut into a circle with the cutting blade cutting into the outer peripheral edge of the corresponding region of the tape corresponding to the second annular region.

3. In the expanding step, the tape is expanded in four directions with the first, second, third, and fourth clamping units. In the relaxation step, each of the first, second, third, and fourth clamping units that clamp the tape is moved by a distance shorter than the moving distance in the expansion step in a direction opposite to the direction in which it was moved in the expansion step, thereby relaxing the stretching of the expanded tape. The pasting method according to claim 1 or 2, characterized in that.

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