JP2001230221A - Wafer cutting equipment and method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide wafer cutting equipment equipped with two spindles and a method wherein the equipment can be improved in cutting efficiency, throughput, and cutting quality by specifying the best directions of rotation of the two spindles. SOLUTION: This dicing equipment 10 cuts out a wafer W by two spindles 34 and 36 which are arranged in face to face with each other and rotating each in opposite directions. When the two spindles 34 and 36 are rotated in the same direction, both a down-cutting and an up-cutting operation can be carried out at the same time. On the other hand, when the spindles 34 and 36 are arranged in parallel and rotated in reverse directions to cut out a wafer W, both a down-cutting and an up-cutting operation can be carried out at the same time.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wafer cutting apparatus and method for cutting a semiconductor wafer into dice by rotating two blades mounted on two spindles.

[0002]

2. Description of the Related Art A dicing apparatus that cuts a semiconductor wafer into dice is a device that cuts a semiconductor wafer into dice along a street by rotating a blade mounted on a spindle at a high speed, and cuts each chip.

[0003] As a conventional dicing apparatus, a dual type dicing apparatus having two spindles is known (Japanese Patent Laid-Open No. 8-25209, Japanese Utility Model Application Laid-Open No. 59-156).
No. 753). According to this dicing apparatus, two streets of the semiconductor wafer can be cut at the same time by two blades, so that there is an advantage that the cutting time of the semiconductor wafer can be reduced.

[0004]

However, in the conventional dual type dicing apparatus, the cutting time can be reduced to almost half by increasing the number of spindles from one to two, but more than that. There is a disadvantage that it cannot be expected to improve the cutting efficiency or to cut the wafer with high quality and high throughput.

In a dicing apparatus, a street is completely cut by one blade, and a street is cut in two steps by using two different blades (half cut by the first blade and second cut of the street). With a full blade). In the former full cut method,
In order to suppress chipping occurring on the surface of the wafer, the rotation direction of the spindle (the rotation direction of the spindle at the cutting point of the blade) is set so that the cutting feed direction of the wafer coincides with the wafer (hereinafter referred to as “down cut”). Name). Also, in the latter half-cutting method of the two-step cutting method, the rotation direction is set to the same as that of the full cutting method in order to suppress chipping on the surface, but when performing the full cutting with the second blade, the wafer is cut. In order to suppress chipping that occurs on the back surface of the wafer, the rotation direction of the spindle and the cutting and feeding direction of the wafer are set in opposite directions (hereinafter, referred to as “up-cut”).

Further, in such a full cut by down cut or a two-stage cut by down cut and up cut, from the viewpoint of improving the throughput,
The wafer is cut when moving in the forward direction, and when moving in the backward direction, the blade is released upward without cutting, and the wafer is returned to the cutting start position at a high speed. In short, in order to perform high-quality cutting in both directions, it is necessary to perform reciprocating processing with a single blade for each reciprocation or to reverse the spindle rotating at high speed, and in any case, the throughput is reduced.

On the other hand, in the dicing apparatus, the cutting is performed while supplying the cutting fluid to the cutting point of the blade. However, the supply of the cutting fluid is also appropriate and reliable from the viewpoint of accurately cutting the semiconductor wafer. Supply is required.

However, in the conventional dual dicing apparatus in which only two spindles are arranged, the cutting fluid supplied to one blade is discharged depending on the mutual position and rotation direction of the spindle. Fluid adversely affects the supply of cutting fluid to the other blade, or the drainage of cutting fluid supplied to the cutting point of each blade is mixed and scattered, so cutting is hindered by the scattered drainage. There was a disadvantage that the liquid could not be reliably supplied to the cutting point. Further, when the effluent is scattered, the cutting powder mixed in the effluent enters the cutting point to cause chipping, or the cutting powder adheres to the chip, which has a disadvantage that the chip is adversely affected.

The present invention has been made in view of such circumstances, and is a wafer cutting apparatus having two spindles, which can efficiently cut a wafer and achieve high quality and high throughput. An object of the present invention is to provide a wafer cutting apparatus and a method thereof.

[0010]

According to the present invention, in order to achieve the above object, two spindles are arranged in a straight line or in parallel, and the two spindles and the wafer are relatively moved. 2 attached to two spindles
In a wafer cutting apparatus that cuts the wafer with a single blade, the two spindles rotate in opposite directions (clockwise and counterclockwise when viewed from the blade side, respectively).

The present invention has been made in order to achieve the above object.
A wafer cutting apparatus having two spindles, the two spindles and the wafer being relatively moved to cut the wafer by two blades mounted on the two spindles; Is characterized in that the respective rotation directions can be switched.

The present invention has been made in order to achieve the above object.
A wafer cutting method for cutting the wafer by two blades mounted on the two spindles by relatively moving the two spindles and the wafer. Is configured such that each rotation direction can be switched, and is characterized in that the two spindles are rotated in directions opposite to each other to cut a wafer.

The present invention has been made in order to achieve the above object.
A wafer cutting method for cutting the wafer by two blades mounted on the two spindles by relatively moving the two spindles and the wafer. Are configured so that their respective rotation directions can be switched, and are characterized in that the two spindles are rotated in the same direction to cut the wafer.

According to the first aspect of the present invention, the two spindles arranged opposite to each other on a straight line are rotated in opposite directions to each other, and the two spindles and the wafer are relatively moved to move the two spindles. The wafer is down-cut or up-cut with a blade. As described above, when the two spindles arranged opposite to each other on a straight line are rotated in opposite directions, the drainage of the cutting fluid supplied to the cutting point of each blade is discharged in the same direction. The drainage scattering prevention cover or the like may be provided only in one side, and the structure is simple. Further, according to the present invention, when cutting is performed in the same cut mode (down cut or up cut), the throughput is higher than that in which two spindles are rotated in the same direction (FIG. 5).

On the other hand, when the two spindles are arranged in parallel, when the two blades are arranged on the same cutting line, the respective cutting fluids are discharged in the opposite direction without being mixed, so that the adjacent cutting fluid is discharged. Does not adversely affect the blade. Therefore, the present invention can reliably supply the cutting fluid to the cutting point (FIG. 10). Also, when two spindles are shifted back and forth and arranged in parallel, down cutting can be performed with the first blade and up cutting can be performed simultaneously with the second different blade, thereby achieving high quality and high throughput. (FIG. 11).

According to a second aspect of the present invention, there is provided a dicing apparatus which has two spindles and is configured to be able to switch the rotation direction of the two spindles, and that the switching can be programmed. In the case where two spindles are arranged opposite to each other and rotated in opposite directions to each other as in the third aspect, the drainage processing structure of the cutting fluid is simplified as in the first aspect of the invention. And high throughput when cutting in the same cutting mode. Further, when the two spindles are rotated in the same direction, the first-stage down-cut and the second-stage up-cut can be performed at the same time, and the two-stage cut with different blades can be performed with high quality and high throughput. On the other hand, when the two spindles are arranged in parallel and rotated in opposite directions, the cutting fluid does not interfere with each other when the two blades are arranged on one straight line. Furthermore, by arranging the two blades shifted in the front-back direction of the spindle axis, the first blade can cut down and the second blade can simultaneously cut up, so that
High quality and high throughput can be achieved by two-stage cutting. Further, in the case of the parallel arrangement and the rotation in the same direction, the drainage scattering prevention structure can be simplified and high throughput can be achieved in the same cut mode cutting (FIG. 12).

According to the fifth aspect of the invention, when the two spindles are rotated in opposite directions to cut the wafer, the drainage processing structure can be simplified when the two spindles are arranged to face each other. In addition, when cutting is performed in the same cutting mode, higher throughput can be achieved as compared with rotation in the same direction (FIG. 5).

When two spindles are arranged in parallel, the cutting fluid can be prevented from interfering with each other, so that the cutting fluid can be reliably supplied to the cutting point. In addition, by arranging the two blades shifted back and forth, two-stage cutting can be performed with high quality and high throughput (FIG. 11).

In the case where the wafer is cut by rotating the two spindles in the same direction as in the invention according to claim 6, when the two spindles are opposed to each other,
Since the first blade can perform the down cut and the second different blade can perform the up cut at the same time, high quality and high throughput can be achieved (FIG. 7). Further, when two spindles are arranged in parallel, when cutting is performed in the same cut mode (down cut or up cut), the throughput is increased and the drainage processing structure can be simplified (FIG. 12).

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of a wafer cutting apparatus and method according to the present invention will be described below in detail with reference to the accompanying drawings.

FIG. 1 is a perspective view of a semiconductor wafer dicing apparatus 10 to which the present invention is applied, and FIG. 2 is a plan view thereof. As shown in FIG. 1, the dicing apparatus 10 includes:
Mainly cutting section 12, cleaning section 14, cassette storage section 1
6, an elevator section 18, a transport device 20, and the like.

The wafer W by the dicing apparatus 10
First, a plurality of wafers stuck to a frame via an adhesive sheet are stored in the cassette storage unit 16. The unprocessed wafers W are sequentially pulled out by the elevator unit 18, and the pulled-out wafers W are set at the position P4 shown in FIG. Next, the wafer W is placed on the cutting table (position P2) (not shown) of the cutting unit 12 via the preload stage at the position P1 by the transfer device 20. Here, the wafer W is held by suction on the cutting table. The wafer W held by suction is subjected to image recognition of the pattern on the wafer W by the alignment imaging devices 22 and 24, and the wafer W is aligned based thereon.

Then, the aligned wafer W is moved in the Y-axis direction indicated by arrows A and B in the cutting section 12 and in the Z-axis direction perpendicular to the plane of the drawing (not shown), and arrows C and D in the cutting table shown in FIG. The chip is cut by a combined operation with the movement in the X-axis direction indicated by. First, the cutting table moves in the X-axis direction, and two streets are simultaneously cut by the two blades 30 and 32 of the cutting blade units 26 and 28. When the first two streets are cut, the cutting blade units 26 and 28 are moved in the Y-axis direction by the pitch of the streets, and the cutting table is moved again in the X-axis direction to move to the next two.
The street of the book is cut by the two blades 30,32. When one street is cut in two steps, the first blade performs only half cutting, and the next blade performs only full cutting to perform two-step cutting. Such a cutting operation is repeatedly performed, and when the cutting of all the streets in one direction (X direction) is completed, the cutting table is rotated by 90 ° and the other direction orthogonal to the cut street (in FIG. The street (Y direction) is sequentially cut by two blades 30 and 32. As a result, the wafer W is cut into a dice, and divided into chips.

After the cut wafer W is returned to the position P2 by moving the cutting table, the transfer device 20
Is transferred to the spinner table of the cleaning unit 14 at the position P3. Here, the wafer W is dried by the air blow after being washed with the washing water. The dried wafer W is transferred to the position P4 by the transfer device 20 and stored in the cassette storage unit 16 by the elevator unit 18. The above is the cutting process of one wafer W by the dicing apparatus 10.

As shown in FIG. 3, the cutting blade units 26 and 28 of the cutting section 12 are provided with a spindle 3 having a built-in high frequency motor.
4 and 36 and blades 30 and 32 mounted on the tips of the spindles 34 and 36. The two spindles 34, 36 of these cutting blade units 26, 28 are
They are arranged to face each other and at positions where their respective axes coincide with the Y-axis direction. Also, the cutting blade unit 26,
28 is connected to a spindle moving mechanism 46 via holders 42 and 44, and is independently moved in the Y-axis direction by the spindle moving mechanism 46. The spindle moving mechanism 46 employs a linear motor, and its detailed configuration is well-known, and thus will not be described here.

FIG. 4 is a detailed view of the tip of the cutting blade unit 26. The cutting blade unit 28 is the cutting blade unit 26
Since the structure is the same as described above, the description of the cutting blade unit 28 is omitted. The upper portion of the blade 30 of the cutting blade unit 26 is covered with a cover called a flange cover 48.
0 and a cutting water supply tube 52 are connected.
The cooling water supply tube 50 is connected to a pair of L-shaped nozzles 54 provided at a lower portion of the flange cover 48. The pair of nozzles 54, 54 are arranged side by side so as to sandwich the blade 30, and the injection ports (not shown) of the nozzles 54, 54 are formed toward the portion where the blade 30 cuts the wafer W. Therefore, the cooling liquid 56 supplied from the cooling water supply tube 50 is supplied to the nozzle 5
4 to the cutting section. Further, the cutting fluid 58 supplied from the cutting water supply tube 52 is supplied from the nozzle 60 provided inside the flange cover 48 to the cutting edge of the blade 30 and adheres thereto. To the cutting point.

Next, a method of cutting the wafer W by the cutting blade units 26 and 28 configured as described above will be described with reference to FIGS.

FIG. 5 shows that the wafer W is moved in the direction C while rotating the two spindles 34, 36 facing each other (arranged on a straight line) in opposite directions.
An example in which is cut down is shown. That is, the spindle 34 moves upward in FIG.
Clockwise as viewed from the direction, the spindle 36
5 is also rotated counterclockwise when viewed from the direction of the arrow B in FIG. 5 (the direction opposite to the direction A) in order to suppress chipping.

Under these conditions, when the wafer W is moved in the direction C, the two streets are simultaneously full-cut by the two blades 30 and 32, and the cut line L1 is formed on the two streets. , L2 are formed.

FIG. 6 is a diagram showing the positional relationship between the wafer W and the cutting blade units 26 and 28 when two streets are fully cut. Thereafter, when the next two streets are fully cut, the blades 30 and 32 are moved in the Y direction by one street pitch after the blades 30 and 32 are released in the Z direction, and the wafer is moved in the D direction at a high speed. To the cutting start position. After this, the blades 30, 32
Is returned to the Z direction, and the wafer W is moved at a low speed in the C direction. The next two streets are simultaneously full-cut by the two blades 30 and 32.

As described above, according to the cutting blade units 26 and 28 of the present embodiment, the two spindles 34 and 36 disposed opposite to each other are rotated in opposite directions. The cutting fluid (drainage) 58, 58 supplied to the cutting point is discharged in the same direction (rotational direction side of the blades 30, 32) as shown by the upper arrow in FIG. The drainage treatment structure can be simplified. Further, in the present embodiment, when cutting is performed in the same cut mode (down cut or up cut), the throughput is higher than that in the case where two spindles are rotated in the same direction.

FIG. 7 shows an example of a pair of cutting blade units in which two spindles 34 and 36 are arranged to face each other and two spindles 34 and 36 are rotated in the same direction. In this example, as shown in FIGS. 8 and 9, the first blade 30 cuts the wafer W down (FIG. 8A) to form a half-cut line La in the wafer W. The cut line La is up-cut (FIG. 8B) by the dissimilar blade 32 to form a full-cut line Lb on the wafer W. According to this cutting method, the first plurality of cuts are performed only by the blade 30, and thereafter, the cut line La cut by the blade 30 is fully cut by the blade 32. Since the full cut at this time can be performed simultaneously with the half cut by the blade 30, high quality and high throughput can be achieved.

FIG. 10 shows an example of a pair of cutting blade units in which two spindles 34 and 36 are arranged in parallel. Also in this cutting blade unit, when the respective spindles 34, 36 are rotated in opposite directions, the respective cutting fluids 58, 58 are discharged in the opposite directions as shown by the upper arrow in FIG. Therefore, there is no adverse effect on the other. Therefore, two spindles 34,
The cutting fluid 58, 58 can be reliably supplied to the cutting point even in the cutting section where the 36 is arranged in parallel. Therefore, a cutting failure such as burn-in does not occur at all in the wafer W, and the chip W is not mixed into the cut portion, so that the wafer W can be cut accurately.

FIG. 11 shows an example of a pair of cutting blade units in which two spindles 38 and 40 are arranged in parallel and shifted by a predetermined amount in the Y direction. Also in this cutting blade unit, when the respective spindles 34, 36 are rotated in opposite directions, the respective cutting fluids 58, 58 are discharged in the opposite direction as shown by the upper arrow in FIG. 11 without being mixed. Does not scatter. Therefore, the wafer W can be cut with high accuracy.

Also, in the cutting blade unit of FIG. 11, the first blade 32 cuts the wafer W down to form a half-cut line on the wafer W, and the second blade 30 cuts the half-cut line. Can be cut up to form a full cut line on the wafer W. According to this cutting method, the first plurality of cuts are performed only by the blade 32, and thereafter, the half cut line cut by the blade 32 is fully cut by the blade 30. Since the full cut at this time can be performed simultaneously with the half cut by the blade 32,
High quality and high throughput can be achieved. When the blades 30 and 32 are reversed with respect to the rotation direction in FIG. 11, the two spindles 34 and 36 are displaced by a predetermined amount in the Y direction, so that the respective cutting fluids 58 and 58 are mixed. Exhausted without fitting. Therefore, also in this case, similarly, the wafer W can be cut with high accuracy. In this case, half cutting is performed by the blade 30 and full cutting is performed by the blade 32.

FIG. 12 shows that two spindles 38 and 40 are arranged in parallel and shifted by a predetermined amount in the Y direction.
In addition, an example of a pair of cutting blade units in which two spindles 38 and 40 are rotated in the same direction is shown. Also in this cutting blade unit, since the two spindles 38, 40 are displaced by a predetermined amount in the Y direction, the respective cutting fluids 58, 58 are discharged without being mixed. Therefore, this cutting blade unit can similarly cut the wafer W with high accuracy. Further, since the cutting fluid supplied to the blades 30 and 32 is discharged in the same direction, the structure such as the scattering prevention cover can be simplified. In addition, when the cutting blade unit performs cutting in the same cut mode (down cut or up cut), throughput increases.

[0037]

As described above, according to the wafer cutting apparatus and method according to the present invention, in a dicing apparatus having two spindles, when two spindles are arranged in a straight line and in a parallel arrangement. 2 when it is done
Since the best rotation direction of the book spindle is specified, the structure of the apparatus can be simplified, the wafer can be cut efficiently, and high quality and high throughput can be achieved.

[Brief description of the drawings]

FIG. 1 is an overall perspective view of a dicing apparatus to which the present invention is applied.

FIG. 2 is a plan view of the dicing apparatus shown in FIG.

FIG. 3 is a plan view showing a structure of a cutting section of the dicing apparatus shown in FIG. 1;

FIG. 4 is a perspective view showing the structure of a cutting blade unit of the cutting section shown in FIG. 3;

FIG. 5 is an explanatory view showing a wafer cutting method by the cutting unit shown in FIG. 3;

FIG. 6 is an explanatory diagram showing a state where two streets are cut by the cutting unit shown in FIG. 3;

FIG. 7 is a plan view of a cutting section for cutting a street in two steps with two opposing spindles;

FIG. 8 is an explanatory view showing a two-stage cutting method performed by the cutting unit shown in FIG. 7;

FIG. 9 is an enlarged sectional view of a semiconductor wafer cut by a two-stage cutting method;

FIG. 10 is a plan view showing the structure of a cutting section in which two spindles are arranged in parallel.

FIG. 11 shows two spindles arranged in parallel and Y
Plan view showing the structure of a cutting section in which the two spindles are rotated in opposite directions while being displaced in the direction.

FIG. 12 shows two spindles arranged in parallel and Y
Plan view showing the structure of a cutting section in which the two spindles are rotated in the same direction while being displaced in the same direction.

[Explanation of symbols]

W: semiconductor wafer, 10: dicing device, 12: cutting unit, 26, 28 ... cutting blade unit, 30, 32 ... blade, 34, 36 ... motor, 38, 40 ... spindle,
46: spindle moving mechanism, 56: cooling fluid, 58: cutting fluid

Claims (6)

[Claims] 1. A method in which two spindles are arranged on a straight line or in parallel, and the two spindles and a wafer are relatively moved to thereby allow the two spindles mounted on the two spindles to move.
A wafer cutting device for cutting the wafer with a single blade, wherein the two spindles rotate in opposite directions to each other. 2. It has two spindles, and by moving the two spindles and the wafer relatively,
In a wafer cutting apparatus for cutting the wafer by two blades mounted on two spindles, the two spindles are configured so that respective rotation directions can be switched. apparatus. 3. The wafer cutting apparatus according to claim 1, wherein the two spindles are arranged to face each other. 4. The wafer cutting apparatus according to claim 1, wherein the two spindles are arranged in parallel. 5. Having two spindles and moving the two spindles and the wafer relatively,
In a wafer cutting method for cutting the wafer by two blades mounted on two spindles, the two spindles are configured such that respective rotation directions are switched, and the two spindles are connected to each other. A wafer cutting method characterized by cutting a wafer by rotating in the opposite direction. 6. Having two spindles and moving the two spindles and the wafer relatively,
In a wafer cutting method for cutting the wafer by two blades mounted on two spindles, the two spindles are configured such that respective rotation directions are switched, and the two spindles are the same. A wafer cutting method characterized by cutting a wafer by rotating in a direction.