JPH08227865A - Cutting method and device of plate-like work - Google Patents

Abstract

PURPOSE: To enable a work such as a wafer to be effectively cut into pieces with blades. CONSTITUTION: A first blade 13 is moved forward in a cutting direction to cut a wafer W, and the first blade 13 stops moving when a second blade 14 moving synchronous with the first blade 13 is positioned over a space S on a cutting start side, and the second blade 14 is moved to approach the space S on a cutting start space S. The blades 13 and 14 are moved to advance for cutting the wafer W at the same time, the second blade 14 stops moving when the first blade 13 reaches a space S on a cutting stop side, the first blade 13 is moved away from the space S on a cutting stop side, and the second blade 14 is moved to the space S on a cutting stop side so as to cut the wafer W.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technique for cutting a plate-like work, and more particularly, it is useful when applied to dicing for dividing a semiconductor wafer (hereinafter referred to simply as a wafer) into small chips or pellets. Regarding technology.

[0002]

2. Description of the Related Art Generally, in manufacturing a semiconductor device, a plurality of predetermined semiconductor elements are simultaneously formed in a regular array by a photolithography technique or the like on a substrate made of a semiconductor such as silicon, that is, a wafer, and then dicing is performed. By cutting the wafer into a lattice by
Dividing into pellets made of individual semiconductor elements is performed.

Such a cutting device is also referred to as a dicing device or a dicer, and has a spindle having a dicing blade having a cutting edge with a thickness of about 20 to 30 μm attached to its tip. A disk-shaped blade attached to the tip of the spindle rotates in a plane perpendicular to the wafer, and the blade is moved in the horizontal direction while being in contact with the wafer. Pellets are formed. Regarding such a dicing technology, for example, "Latest Semiconductor Improvement Automation System" published by Science Forum Co., Ltd., July 25, 1984, P13
4 to P137.

Since the bottom surface of each of the pellets obtained by cutting the wafer is adhered and fixed to the adhesive sheet, the mutual positional relationship in the wafer state is maintained even after the dicing, and the pellets after the dicing are collected. Work or the like is accurately performed based on the position information of each pellet in the wafer state.

The wafer to be diced is fixed by vacuum suction to a supporting base which is attached with a work sheet made of an adhesive sheet and is held by using a frame body also called a wafer frame. The adhesive sheet is attached and fixed to the central portion of the adhesive sheet so as to form a predetermined space between the adhesive sheet and the frame. Therefore, an annular space is formed between the inner peripheral surface of the frame body and the outer peripheral surface of the wafer, and the blade moves into the space on the opposite side after entering the space. Then, the cutting operation for one line is completed.

[0006]

On the other hand, in order to improve the wafer cutting efficiency, a dual spindle type dicing apparatus using two blades has been studied by the inventor. As a result of the examination, when the two spindles are moved in synchronization with each other, the space into which the blade is inserted is secured only for one blade, so that the blade interferes with the frame. It will be. Therefore, when two blades are used, the cutting operation cannot be performed by these blades at the same time, and the throughput is reduced.

Therefore, it has been attempted to use an expandable sheet made of a highly stretchable material as a work sheet, and to pull down only the frame body from the surface of the support base to stretch the adhesive sheet. According to this method, it is possible to perform the cutting work at the same time by the two blades, but the work sheet urges the pellet to exert an action force for horizontally shifting the pellet,
When the pellets were directly picked up in a later collecting operation, there were cases where the pellets could not be accurately grasped due to the positional displacement.

An object of the present invention is to efficiently cut a work such as a wafer into small pieces by using a plurality of blades.

The above and other objects and novel features of the present invention will be apparent from the description of this specification and the accompanying drawings.

[0010]

Of the inventions disclosed in the present application, a representative one will be briefly described below.
It is as follows.

That is, the plate-shaped workpiece cutting method of the present invention, when one of the leading blade and the trailing blade moves toward or away from the space between the frame and the workpiece, The other blade also stops moving in the cutting direction. The respective blades may cut different parts of the work from each other, or may cut the same part in a plurality of steps. When cutting in two steps with two blades, the leading blade is downcut and the following blade is upcut.

In the plate-shaped workpiece cutting apparatus of the present invention, a plurality of spindles each having a blade on the XY table are independently movable in the direction perpendicular to the surface of the workpiece, and the XY table is cut and transferred. Thus, the blades move synchronously in the cutting direction.
When one blade moves toward and away from the space between the frame and the work, the other blades stop moving.

[0013]

In the method and apparatus for cutting a plate-shaped work, when the blades are moved toward or away from the space, they do not move in the cutting proceeding direction. Inadvertent contact between the blade and the frame or the work can be avoided without widening the space between them, and the work can be efficiently cut into small pieces while increasing the product yield. Further, by using a plurality of blades, it is possible to cut the work divided into two stages or to cut different parts at the same time, and the work can be cut efficiently.

[0014]

Embodiments of the present invention will now be described in detail with reference to the drawings.

FIG. 1 is a plan view showing a dicing device which is a cutting device for a plate-like work according to the present invention, and FIG. 2 is a sectional view of the front side of FIG.

A wafer W, which is a plate-like work, is attached to and held by a frame body 2 having an adhesive work sheet 1 attached to the work sheet 1. An annular space S is formed between the outer peripheral surface of the wafer W attached to the worksheet 1 and the inner peripheral surface of the frame body 2. The frame body 2 is supported by a support base 3 by vacuum suction or the like, and the support base 3 indexes and rotates the frame body 2 at 90 degrees. As the worksheet, a relatively hard sheet that does not have high elasticity is used.

An XY table 4 is arranged adjacent to the support base 3, and the XY table 4 is parallel to the surface of the wafer W and is movable in two directions of XY which are perpendicular to each other. . The XY table 4 is provided with two sliding blocks 5 and 6 slidably in the vertical direction, that is, the Z direction, and one sliding block 5 has a first sliding block.
A spindle 11 is rotatably provided, and the other sliding block 6 is provided with a second spindle 12. First
The spindle 11 is the leading side spindle, and the second
The spindle 12 is a follow-up spindle. These spindles 11 and 12 are displaced from each other in the X direction.

Blades 13 and 14 for dicing are mounted on the tips of the respective spindles 11 and 12, the first blade 13 is a leading blade, and the second blade 14 is a trailing blade. Since the respective sliding blocks 5 and 6 are provided on the XY table 4, they are moved in the X direction and the Y direction in synchronization. The respective sliding blocks 5 and 6 are independently movable with respect to the XY table 4 in a direction perpendicular to the surface of the wafer W, that is, in the vertical direction in FIG. 2, and both spindles 11 and 12 are also independent. And it is movable up and down.

In the illustrated dicing apparatus, since the wafer W is cut when the XY table 4 is moved from the left side to the right side in FIGS. 1 and 2, the first blade 1
Although 3 is the leading blade and the second blade is the trailing blade, when the wafer W is cut when moving the XY table 4 from the right side to the left side, the second blade 14 becomes the leading blade. The first blade serves as the following blade.

FIG. 3 is a diagram showing a control circuit of the dicing apparatus. A motor 21 for rotating the support base 3, a motor 22 for driving the XY table 4 in the X direction, a motor 23 for driving the Y direction, and a sliding block. A motor 24 for driving the sliding block 6 in the Z direction and a motor 2 for driving the sliding block 6 in the Z direction.
5, a drive signal is sent from the drive control unit 27 to the motor 26 for rotationally driving the blades 13 and 14, and the motors 26 are driven at predetermined timings.

Next, the operation of cutting the wafer W by the dicing device will be described with reference to FIG.

First, the XY table 4 is moved rightward in FIG. 2 so that the first blade 13 is located right above the space S on the cutting start side as shown in FIG. The traveling movement of the table 4 is stopped. Then
The sliding block 5 is moved downward to move the first spindle 11, that is, the first spindle 11, as shown by a chain double-dashed line in FIG.
The blade 13 is moved closer to the space S. As described above, the first movement is performed with the traveling movement of the XY table 4 stopped.
Since the blade 13 is moved downward, the first blade 13
Will move down to the cutting start position without contacting the frame 2 and the wafer W even if the width of the space S is minimized.

Under this condition, the XY table 4 is moved rightward in FIG. 2 to cut the wafer W by the first blade 13. This first blade 13 is shown in FIG.
As shown in (a), the width is L _1, and the wafer W is cut by the depth D with a width corresponding to this. As the cutting progresses, as shown in FIG. 4B, the second blade 1
When 4 reaches the position of the space S on the cutting start side, the moving movement of the XY table 4 is stopped, and the second blade 14 is moved toward the space S as shown in FIG. 4C. The stop time of the forward movement is the time required for the approach movement, and in the illustrated case, it is set to about 0.1 to 0.15 seconds.

Next, the XY table 4 is moved in the cutting advancing direction, and the wafer W is cut by both blades 13 and 14. Therefore, as shown in FIG. 5B, the second blade 14 has a width L narrower than that of the first blade 13 after the first blade 13 cuts by a predetermined depth D.
Completely cut with ₂ . This allows the two blades 1
As shown in FIG.
As shown in, the wafer W is cut into a stepwise cut surface.

By moving the XY table 4,
When both blades 13 and 14 move in the cutting advancing direction, as shown in FIG. 4D, when the first blade 13 advances and moves to the space S on the cutting end side,
The XY table 4 is stopped to stop the progress of both blades 13 and 14. Under this state, as shown in FIG. 4E, the sliding block 5 is moved upward to move the first blade 13 away from the space S on the cutting end side.

When the separating movement is completed, the XY table 4 is moved again in the cutting advancing direction, and the first blade 13 is moved.
The second blade 14 cuts the portion that has been cut by. In this way, when the cutting work by the second blade 14 is completed and the second blade 14 reaches the position of the space S on the cutting completion side, the cutting work for one line is completed.

After that, the XY table 4 is returned to the cutting start side, the XY table 4 is shifted by one pitch in the Y direction, and the above cutting operation is repeated. After a predetermined number of cutting operations are completed in parallel to the wafer W, the support base 3 is rotated 90 degrees, and similar cutting operations are performed at predetermined intervals. In this way, the wafer W is cut into a lattice shape to form a plurality of pellets.

In the dicing device, when either the first blade 13 or the second blade 14 is moved toward or away from the space S, the progressive movement of both blades is stopped. Therefore, since the blades 13 and 14 do not move in the traveling direction during the movement, even if the gap size of the space S is made as narrow as possible, the blade and the frame body 2 or the wafer W are not prepared. It is possible to avoid high contact and efficiently cut high quality pellets.

FIG. 6 is a view showing the rotation directions of the respective blades 13 and 14, and in the case shown, the first blade 13 is rotated in the downcut direction, and the second blade 1 is rotated.
4 is rotated in the upcut direction. The down-cut is a method of rotating the blade 13 in the same direction as the wafer W feeding direction as shown in FIG. 6A, and the up-cut is a method of feeding the wafer W as shown in FIG. 6B. This is a method of rotating the blade 14 in the direction opposite to the direction.

As described above, when the first blade 13 is rotated in the down-cut direction, the front surface side of the wafer W becomes a sharp cutting surface, but chipping C occurs on the bottom surface side of the cutting groove or cracks easily occur. Is likely to occur. Conversely, when the second blade 14 is rotated in the up-cut direction, the bottom surface side of the wafer W becomes a sharp cutting surface, but the wafer W
On the surface side of, chipping easily occurs. But the second
The front side of the wafer W by the blade 14 is the first blade 1
Since the groove is cut to a predetermined depth D by 3, chipping is prevented from occurring at the bottom surface of this groove.

Therefore, by rotating the first blade 13 in the down-cut direction and the second blade 14 in the up-cut direction, cracks and chipping are not generated on the entire cut surface, and high quality cutting is performed. The product yield will be improved.

In the illustrated embodiment, after the first blade 13 cuts to a predetermined depth, the remaining portion is cut by the second blade 14, but each of them is cut at a predetermined pitch in the Y direction of FIG. It is also possible to cut at two locations at the same time, that is, for two lines, by shifting only. Alternatively, both blades 13 and 14 may be rotated in the same direction to perform downcut or upcut. Further, in the case shown in the drawing, after the cutting operation of one line is completed, the XY table 4 is returned to the starting point position to perform the cutting of another portion, but the cutting is also performed when returning the XY table 4. You may do it. That is, the cutting may be performed by both the reciprocating movement of the XY table 4, and in that case, the blades 13,
The direction of rotation of 14 may be reversed between the forward movement and the backward movement. When the wafer W is also cut when returning the XY table 4, the blade 14 becomes the first blade, that is, the leading blade, and the blade 13 becomes the second blade, that is, the following blade, when returning.

Although the invention made by the present inventor has been specifically described based on the embodiments, the present invention is not limited to the embodiments and various modifications can be made without departing from the scope of the invention. Needless to say.

For example, in the illustrated embodiment, two spindles 11 and 12 are mounted on one dicing machine and cutting is performed by two blades 13 and 14, but three spindles are used. It may be attached. In that case, by disposing three blades in the X direction, the second blade becomes a follower blade with respect to the first blade and becomes a leading blade with respect to the third blade. . The relationship between the leading blade and the trailing blade operates at the same timing as in the case described above. The number of blades, that is, the number of spindles may be three or more.

FIG. 7 is a diagram showing, as a comparative example, a case where an expansion sheet having high elasticity is used as the work sheet 1 as described above. In this case, the technique of the present invention is not applied to the wafer W. Although the cutting can be performed, as described above, the work sheet urges each part of the wafer W with an action force that horizontally shifts the part, and the pellets after cutting may be displaced.

On the other hand, in the technique of the present invention, such a phenomenon does not occur and workability is greatly improved.

In the above description, the case where the invention made by the present inventor is mainly applied to the semiconductor wafer dicing technology, which is the field of use thereof, has been described, but the invention is not limited to this and, for example, a plate-shaped workpiece. It can be applied to any work as long as it is cut into small pieces.

[0038]

Advantageous effects obtained by typical ones of the inventions disclosed in the present application will be briefly described.
It is as follows.

(1). It is possible to efficiently perform high-throughput cutting of a work having a complicated cross-sectional shape such that the same line is divided into a plurality of times.

(2). One cutting can be efficiently performed by a plurality of blades, and a plurality of cutting lines can be simultaneously cut by using blades having the same width.

(3). Down-cutting and up-cutting can be performed with a plurality of blades having mutually different rotation directions.

(4). After cutting the work, the cut pieces are not displaced by the work sheet, and the workability is greatly improved.

[Brief description of drawings]

FIG. 1 is a plan view showing a dicing device that embodies a cutting device for a plate-shaped work according to an embodiment of the present invention.

FIG. 2 is a sectional view of the front side of FIG.

FIG. 3 is a block diagram showing a control circuit.

FIG. 4A to FIG. 4E are process diagrams showing a wafer cutting method using a dicing device.

5A to 5C are cross-sectional views showing the cross-sectional shape of the wafer after being cut.

FIG. 6A is a sectional view showing a cutting operation of a first blade by down cutting, and FIG. 6B is a sectional view showing a cutting operation of a second blade by up cutting.

FIG. 7 is a front side sectional view showing a dicing device as a comparative example.

[Explanation of symbols]

 1 Worksheet 2 Frame 3 Support 4 XY Table 5, 6 Sliding Block 11 1st Spindle (Preceding Side Spindle) 12 2nd Spindle (Following Side Spindle) 13 1st Blade (Preceding Side Blade) 14 2nd Blade ( Following blade) 21 to 26 Motor 27 Drive control unit (drive control means) W Wafer (plate work)

Claims (6)

[Claims] 1. A method for cutting a plate-shaped work, comprising cutting a plate-shaped work held by the worksheet into a frame body having a worksheet through an annular space with respect to the frame body, the method comprising: The side blade is moved closer to the space on the cutting start side of the plate-like work, the front side blade is moved in the cutting direction to cut the plate-like work, and the side blade is moved in synchronization with the preceding side blade. When the trailing side blade to the position of the space of the cutting start side to stop the advance movement of the leading side blade to move the trailing side blade closer to the space of the cutting start side, the leading side and the trailing side of When the blades are moved to cut the plate-like work at the same time by the blades, the trailing side moves when the leading blade moves to the space on the cutting end side. Stop the progressive movement of the blade to move the leading blade away from the space on the cutting end side, and then move the trailing blade to the space on the cutting end side to cut the plate-like work. A method for cutting a plate-shaped work, characterized in that 2. The method for cutting a plate-shaped work according to claim 1, wherein the leading blade cuts the plate-shaped work at a predetermined depth, and the trailing-side blade cuts the remaining portion, A method for cutting a plate-like work, wherein the leading blade performs down-cut and the trailing blade performs up-cut. 3. A plate-like work cutting device for cutting a plate-like work, which is held by the worksheet into a frame body having a worksheet through an annular space with respect to the frame body, into small pieces. A support base for supporting a frame body holding a plate-like work, and an XY arranged adjacent to the support base and movable in two directions parallel to the surface of the plate-like work and perpendicular to each other.
A table, a XY table movably provided in a direction perpendicular to the surface of the plate-like work, and a leading-side spindle having a leading-side blade at the tip, and a movable in a direction perpendicular to the surface of the plate-like work. ,
And is provided on the XY table while being displaced in a direction along the surface of the plate-like work with respect to the leading-side spindle,
A plate-like work characterized by having a follow-up spindle having a follow-up blade at its tip, and a drive control unit that independently drives each of the spindles to move freely in a direction perpendicular to the surface of the plate-like work. Cutting device. 4. The cutting device for plate-like work according to claim 3, wherein the drive control unit performs cutting of the plate-like work by the leading blade, and the follower blade is on a cutting start side. When the XY table is moved forward to the space, the movement of the XY table is stopped and the follower blade is moved closer to the space. When the leading blade is moved to the space on the cutting end side, the XY table is moved. A cutting device for a plate-like workpiece, characterized in that the forward movement is stopped to separate the leading blade from the space. 5. The plate-shaped workpiece cutting device according to claim 3, wherein each of the leading side spindle and the trailing side spindle is provided with one spindle. Cutting device. 6. The cutting device for a plate-like work according to claim 3, wherein the plate-like work is a semiconductor wafer.