Segmentation device

Abstract

The present invention provides a splitting apparatus that can reliably split a wafer, in which a splitting trigger has been formed on the planned splitting line, into individual device chips. [Solution] The splitting device 2 includes a table 4 that supports a wafer W disposed on a frame F having an opening Fa for housing the wafer W via tape T, a pair of support bars 6 disposed to sandwich a planned splitting line L and supporting the wafer W via tape T, and a pressing means 8 that includes a pressing bar 58 that presses the planned splitting line L of the wafer W supported by the pair of support bars 6 to split the wafer W. The pressing means 8 includes a plurality of pressing bars 58 of different lengths, and the pressing bars 58 can be appropriately selected according to the length of the planned splitting line L.

Description

Technical Field

[0001] The present invention relates to a dicing device for dicing a wafer in which a dicing trigger is formed on a planned dicing line.

Background Art

[0002] A wafer on which a plurality of devices such as ICs and LSIs are partitioned by a planned dicing line and formed on the surface is ground on the back surface to a predetermined thickness and then diced into individual device chips by a dicing device, and each diced device chip is used in electrical devices such as mobile phones and personal computers.

[0003] In addition, a technique has also been proposed in which a dicing trigger is created on the planned dicing line of a wafer by a laser processing device, and then an external force is applied to the wafer to dice the wafer into individual device chips (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, there is a problem that there are cases where sufficient external force is not applied to the planned dicing line where the dicing trigger is formed, and the wafer cannot be reliably diced into individual device chips.

[0006] An object of the present invention is to provide a dicing device capable of reliably dicing a wafer in which a dicing trigger is formed on a planned dicing line into individual device chips.

Means for Solving the Problems

[0007] According to the present invention, the following dividing device is provided that solves the above problems. That is, "A splitting device for splitting a wafer in which a splitting trigger has been formed on a planned splitting line, A table supporting wafers, which are arranged via tape on a frame having an opening for housing wafers, A pair of support bars are positioned to sandwich the planned division line and support the wafer via tape, The system includes a pressing means comprising a pressing bar for pressing a wafer along a planned splitting line on a wafer supported by a pair of support bars to split the wafer, The provided dividing device includes a plurality of pressing bars of different lengths, the pressing bars of which can be appropriately selected according to the length of the dividing line.

[0008] Preferably, the pressing means includes a rotating shaft, and a plurality of pressing bars are arranged radially on the rotating shaft. The table preferably includes a frame holding portion for holding the frame and an opening for bringing the wafer to face the support bar via a tape. [Effects of the Invention]

[0009] The present invention is a splitting apparatus for splitting a wafer in which a splitting trigger has been formed on a splitting line, A table supporting wafers, which are arranged via tape on a frame having an opening for housing wafers, A pair of support bars are positioned to sandwich the planned division line and support the wafer via tape, The system includes a pressing means comprising a pressing bar for pressing a wafer along a planned splitting line on a wafer supported by a pair of support bars to split the wafer, The pressing means includes a plurality of pressing bars of different lengths, and the pressing bars can be appropriately selected according to the length of the planned division line, so that a wafer in which a division trigger has been formed along the planned division line can be reliably divided into individual device chips. [Brief explanation of the drawing]

[0010] [Figure 1] A perspective view of the dividing device according to the present invention. [Figure 2] (a) Exploded perspective view of the table and support bar shown in Figure 1, (b) Perspective view of the table and support bar shown in (a). [Figure 3] A perspective view of the support bar shown in Figure 1. [Figure 4] A perspective view of the pressing mechanism shown in Figure 1. [Figure 5] A schematic diagram illustrating the formation of the splitting mechanism on the wafer. [Figure 6] A schematic cross-sectional view of a wafer when the splitting mechanism is being formed. [Figure 7] A schematic diagram of the wafer being split using the splitting device shown in Figure 1. [Modes for carrying out the invention]

[0011] Hereinafter, preferred embodiments of the dividing device according to the present invention will be described with reference to the drawings.

[0012] (splitting device 2) As shown in Figure 1, the splitting device 2 includes a table 4 that supports a wafer W disposed on a frame F having an opening Fa for housing the wafer W via tape T, a pair of support bars 6 disposed to sandwich a planned splitting line L and supporting the wafer W via tape T, and a pressing means 8 equipped with a pressing bar that presses the planned splitting line L of the wafer W supported by the pair of support bars 6 to split the wafer W.

[0013] (Table 4 of the splitting device 2) Referring to FIGS. 1 and 2, table 4 includes a top plate 10 for supporting wafer W and a pair of legs 12 (see FIG. 2(a)) for rotatably supporting the top plate 10. The outer periphery of the top plate 10 in this embodiment is circular. As shown in FIG. 1, a belt 14 is wound around the outer periphery of the top plate 10. The belt 14 is also wound around a pulley 18 mounted on the output shaft 16a of the motor 16. As shown in FIG. 2(a), a plurality of bearings 20 for rotatably supporting the top plate 10 are mounted on the upper ends of the pair of legs 12. The top plate 10 is configured to be rotated by the motor 16 via the belt 14 about the Z-axis direction (vertical direction) indicated by arrow Z in FIG. 1. The X-axis direction indicated by arrow X in FIG. 1 is perpendicular to the Z-axis direction, and the Y-axis direction indicated by arrow Y in FIG. 1 is perpendicular to both the X-axis direction and the Z-axis direction. The XY plane defined by the X-axis direction and the Y-axis direction is substantially horizontal.

[0014] Further, the table 4 includes a frame holding portion 22 for holding the frame F and an opening 24 for facing the wafer W to the pair of support bars 6 via the tape T. The frame holding portion 22 may have a configuration including a plurality (four in this embodiment) of clamps for pressing the frame F against the upper surface of the top plate 10. The opening 24 is rectangular and provided at the center of the top plate 10.

[0015] (Support bar 6 of the dividing device 2) As shown in FIG. 3, the pair of support bars 6 includes a first support bar 6a and a second support bar 6b whose distance from the first support bar 6a can be adjusted. The first and second support bars 6a and 6b are positioned at the opening 24 of the table 4 and are formed in a plate shape extending in the Y-axis direction. At the upper ends of the first and second support bars 6a and 6b, a plurality of suction portions 26 are provided at intervals in the Y-axis direction. The suction portion 26 is formed of a porous member such as porous ceramics. Further, the suction portion 26 is connected to a suction means (not shown). Then, the first and second support bars 6a and 6b are adapted to suck and support the wafer W via the tape T by generating a suction force at the suction portion 26 by the suction means. Note that the plurality of suction portions 26 are configured to be able to control a portion that generates a suction force and a portion that does not generate a suction force. Therefore, at the suction portion 26, the portion that generates a suction force is appropriately adjusted according to the diameter of the wafer W.

[0016] Continuing the description with reference to FIG. 3, the first support bar 6a is attached to a first X-axis movable member 28 provided so as to be movable in the X-axis direction. The second support bar 6b is attached to a second X-axis movable member 30 provided so as to be movable in the X-axis direction on the first X-axis movable member 28.

[0017] The first X-axis movable member 28 is adapted to be moved in the X-axis direction by a first X-axis feed means 32. The first X-axis feed means 32 may be, for example, a ball screw type having a ball screw 34 connected to the first X-axis movable member 28 and extending in the X-axis direction, and a motor 36 for rotating the ball screw 34. Then, the first X-axis feed means 32 converts the rotational motion of the motor 36 into a linear motion by the ball screw 34 and transmits it to the first X-axis movable member 28, and moves the first X-axis movable member 28 in the X-axis direction along a pair of guide rails 38. Thereby, the position of the first support bar 6a in the X-axis direction is adjusted.

[0018] The second X-axis movable member 30 is moved in the X-axis direction by a second X-axis feed means 40. The second X-axis feed means 40 may be a ball screw type having a ball screw 42 connected to the second X-axis movable member 30 and extending in the X-axis direction, and a motor 44 that rotates the ball screw 42. In this embodiment, a pair of second X-axis feed means 40 are provided, but the second X-axis feed means 40 may be single. The second X-axis feed means 40 converts the rotational motion of the motor 44 into linear motion using the ball screw 42 and transmits it to the second X-axis movable member 30, moving the second X-axis movable member 30 in the X-axis direction. This adjusts the X-axis position of the second support bar 6b ​​relative to the first support bar 6a.

[0019] (Pressing means 8 of the splitting device 2) The pressing means 8 will be described with reference to Figure 4. The pressing means 8 comprises an X-axis guide member 46 extending in the X-axis direction, an X-axis movable member 48 supported by the X-axis guide member 46 so as to be movable in the X-axis direction, an X-axis feed means 50 for moving the X-axis movable member 48 in the X-axis direction, a Z-axis movable member 52 supported by the X-axis movable member 48 so as to be movable in the Z-axis direction, and a Z-axis feed means 54 for moving the Z-axis movable member 52 in the Z-axis direction. The Z-axis movable member 52 is rotatably supported by a rotating shaft 56, and is provided with a motor (not shown) for rotating the rotating shaft 56 with the Y-axis direction as its axis. As shown in Figure 4, a plurality of pressing bars 58 of different lengths in the Y-axis direction are arranged radially on the rotating shaft 56. The tip portion of the pressing bar 58 is formed in a triangular cross-section, with the thickness gradually decreasing towards the tip. The X-axis feed means 50 and the Z-axis feed means 54 of the pressing means 8 may both be ball screw type.

[0020] (Waha W) The disc-shaped wafer W shown in Figures 1 and 5 can be formed from a suitable semiconductor material, such as silicon. The surface Wa of the wafer W is divided into multiple rectangular regions by grid-like division lines L. A device D, such as an IC or LSI, is formed in each of the multiple rectangular regions. The wafer W is also disposed on an annular frame F having a circular opening Fa that houses the wafer W, via a tape T.

[0021] (This creates the trigger for the splitting of wafer W) To create a starting point for splitting along the planned splitting line L of the wafer W, for example, the laser processing apparatus 60 shown in Figure 5 can be used. The laser processing apparatus 60 comprises a chuck table (not shown) for holding the wafer W by suction, an oscillator (not shown) that emits a pulsed laser beam LB with a wavelength that is transparent to the wafer W, and a concentrator 62 that focuses the laser beam LB emitted by the oscillator and irradiates the wafer W held by suction on the chuck table.

[0022] To create a starting point for splitting along the planned splitting line L of the wafer W, first, the wafer W is held in place by suction using the chuck table of the laser processing apparatus 60. Next, the wafer W is imaged from above using the imaging means (not shown) of the laser processing apparatus 60, and the planned splitting line L is aligned in the X-axis direction based on the image of the wafer W captured by the imaging means. Then, the laser beam LB is aimed at the planned splitting line L aligned in the X-axis direction, and the focal point of the laser beam LB is positioned inside the wafer W. Next, as shown in Figure 6, while the chuck table is processed and fed in the X-axis direction, a laser beam LB with a wavelength that is transparent to the wafer W is irradiated onto the wafer W from the focuser 62. This allows the modified layer 64, which serves as a starting point for splitting, to be formed inside the wafer W along the planned splitting line L.

[0023] Next, the focal point is indexed and fed in the Y-axis direction by the distance of the division line L in the Y-axis direction, and then, as described above, the laser beam LB is irradiated onto the wafer W to form a modified layer 64 inside the wafer W along the division line L. Then, by alternately repeating the irradiation of the laser beam LB and indexing and feeding, the modified layer 64 is formed inside the wafer W along all of the division line L aligned in the X-axis direction. After rotating the chuck table by 90 degrees, the irradiation of the laser beam LB and indexing and feeding are alternately repeated. In this way, the modified layer 64 is formed along all of the division line L that are orthogonal to the division line L on which the modified layer 64 was previously formed. In this way, a grid-like modified layer 64, which serves as a trigger for division, is formed inside the wafer W along the grid-like division line L.

[0024] (The wafer W is divided by the dividing device 2) Once the splitting trigger is formed on the planned splitting line L of the wafer W, the wafer W is split into individual device chips using the splitting device 2 described above. When splitting the wafer W, first, the wafer W is placed with the top plate 10 of the table 4 facing upwards, and then the frame F is held by the frame holding part 22 of the table 4, thereby supporting the wafer W on the table 4.

[0025] After supporting the wafer W on the table 4, the wafer W is supported via tape T by a pair of support bars 6. In this process, first, the imaging means (not shown) of the splitting device 2 images the wafer W from above, and the planned splitting line L is aligned in the Y-axis direction based on the image of the wafer W captured by the imaging means. Next, the first and second X-axis movable members 28 and 30 are moved by the first and second X-axis feeding means 32 and 40 to position the pair of support bars 6 (first and second support bars 6a and 6b) below the planned splitting line L. Specifically, as shown in Figure 7, the pair of support bars 6 are positioned with a gap between them so as to sandwich the planned splitting line L on which the modified layer 64 is formed. Next, a suction force is generated in the suction part 26 by the suction means, and the wafer W is supported by the pair of support bars 6 via tape T.

[0026] After supporting the wafer W via the tape T with a pair of support bars 6, the wafer W is divided by pressing the division line L with a pressing bar 58. In this process, first, the rotation axis 56 of the pressing means 8 is rotated to point the pressing bar 58 downward according to the diameter of the wafer W. Next, the X-axis feed means 50 of the pressing means 8 is activated to adjust the X-axis position of the downward-pointing pressing bar 58. Specifically, the pressing bar 58 is positioned between the pair of support bars 6 in the X-axis direction. Then, as shown in Figure 7, the pressing bar 58 is lowered and pressed against the division line L between the pair of support bars 6. As a result, since the modified layer 64, which acts as a trigger for division, is formed on the division line L, the wafer W is divided along the division line L pressed by the pressing bar 58.

[0027] After dividing the wafer W along the division line L, the pressing bar 58 is raised and the suction force of the suction parts 26 of the pair of support bars 6 is released. Next, the pair of support bars 6 are moved in the X-axis direction by the distance of the division line L. That is, the pair of support bars 6 are positioned so that they sandwich the undivided division line L located next to the previously divided division line L. Next, a suction force is generated in the suction parts 26 by the suction means, and the wafer W is supported by the tape T through the pair of support bars 6. The pressing bar 58 is also moved in the X-axis direction by the distance of the division line L, so that the pressing bar 58 is positioned between the pair of support bars 6 in the X-axis direction. Then, the pressing bar 58 is lowered and pressed against the division line L between the pair of support bars 6, thereby dividing the wafer W along the division line L.

[0028] As described above, the wafer W is divided along all of the division lines L aligned in the Y-axis direction by repeatedly moving the pair of support bars 6 and pressure bars 58 by the distance of the division lines L and using the pressure bars 58. Then, the top plate 10 of the table 4 is rotated 90 degrees, and the wafer W is divided along all of the division lines L by repeatedly moving the pair of support bars 6 and pressure bars 58 by the distance of the division lines L and using the pressure bars 58. This divides the wafer W along all of the division lines L that are orthogonal to the previously divided division lines L. In this way, the wafer W is divided into individual device chips along the grid-like division lines L.

[0029] In the splitting apparatus 2 of this embodiment, the pressing means 8 is equipped with a plurality of pressing bars 58 of different lengths. By appropriately selecting a pressing bar 58 corresponding to the length of the planned splitting line L, sufficient external force can be applied to the planned splitting line L where the splitting trigger (modified layer 64) is formed. Therefore, the wafer W can be reliably split into individual device chips. [Explanation of symbols]

[0030] 2: Splitting device 4: Table 6: Support bar 6a: First support bar 6b: Second support bar 8: Pressing means 22: Frame holding part 24: Opening 56: Rotation axis 58: Pressure bar 64: Modified layer (the trigger for the split)

Claims

1. A splitting device for splitting a wafer in which a splitting trigger has formed on a planned splitting line, A table supporting wafers, which are arranged via tape on a frame having an opening for housing wafers, A pair of support bars are positioned to sandwich the planned division line and support the wafer via tape, The system includes a pressing means comprising a pressing bar for pressing a wafer along a planned splitting line on a wafer supported by a pair of support bars to split the wafer, The pressing means comprises a plurality of pressing bars of different lengths, and the pressing bars can be appropriately selected according to the length of the line to be divided.

2. The dividing device according to claim 1, wherein the pressing means comprises a rotating shaft, and a plurality of pressing bars are arranged radially on the rotating shaft.

3. The splitting device according to claim 1, further comprising a table, a frame holding portion for holding a frame, and an opening for bringing a wafer to face a support bar via tape.

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