JPH07335595A - Rocking slicing method for semiconductor wafer - Google Patents

Abstract

PURPOSE:To obtain a rocking slicing method in which the feeding movement speed of an internal circumferential blade or a semiconductor material is decelerated gradu ally after starting a rocking operation, in which the speed is decelerated so as to become a minimum speed immediately before finishing the rocking operation, in which the speed is accelerated after reaching the minimum speed, in which the speed is returned to a speed at the start of the rocking operation after finishing the rocking operation and in which a cutting load applied to the internal circumferential blade is made uniform. CONSTITUTION:The feeding movement speed of an internal circumferential blade 10 in one rocking operation is decelerated gradually after starting a rocking operation. Then, the speed is decelerated so as to become a minimum speed immediately before finishing the rocking operation. After the speed has reached the minimum speed, it is accelerated, and it is controlled so as to be returned to a speed at the start of the rocking operation when the rocking operation is finished. When the feeding movement speed of the internal circumferential blade 10 is controlled in this manner, the mountain of the peak value of a maximum cutting amount becomes gentle. As a result, the cutting work load of the internal circumferential blade 10 can be made uniform, and a sudden load in a cutting operation is not applied, and the product life of the internal circumferential blade 10 can be extended.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a swing slicing method for a semiconductor wafer by an inner peripheral blade type slicing machine.

[0002]

2. Description of the Related Art Conventionally, in slicing a semiconductor wafer with an inner peripheral blade, a semiconductor material is fed in a cutting direction while rotating the inner peripheral blade to cut the semiconductor material with the inner peripheral blade. However, in this slicing method, when the inner diameter of the inner peripheral blade is D ₁ and the outer diameter is D ₂ , the diameter difference between the inner and outer diameters of the inner peripheral blade [(D ₂ −D ₁ ) / 2] (hereinafter, “ The effective blade crossing distance) must be larger than the diameter D of the semiconductor material.

The inner peripheral blade is formed by stamping a rolled strip-shaped thin plate. Since the inner peripheral blade is circular in appearance, it does not have directionality, but is inherently in the rolling direction. There is a difference in tensile strength between and the direction orthogonal to this. Therefore, when the diameter of the inner peripheral blade increases, it becomes difficult to adjust the tension of the inner peripheral blade.

[0004]

Therefore, in the above method, the inner and outer diameters of the inner peripheral blade are increased with the increase in the diameter of the semiconductor material, so that the rigidity of the inner peripheral blade is decreased and the processing accuracy of the semiconductor EUH is improved. There is a disadvantage that the tension of the inner peripheral blade becomes extremely difficult to adjust with the decrease. The present invention has been made in view of such circumstances, and an object of the present invention is to provide a swing slicing method for a semiconductor wafer in which the effective blade crossing of the inner peripheral blade can be made smaller than the diameter of the semiconductor material.

[0005]

In order to achieve the above object, the invention provides a method of swing slicing a semiconductor wafer according to the present invention. The feed moving speed of the blade or the semiconductor material is gradually decelerated after the start of the swing and is reduced to the minimum speed immediately before the end of the swing, and is accelerated after reaching the minimum speed, and when the swing ends, the swing starts. It is characterized by returning to the speed of.

In order to achieve the above-mentioned object, the semiconductor wafer oscillating slicing method according to claim 2 has a oscillating angular velocity of the semiconductor material within a unidirectional oscillating range of the semiconductor material. It is characterized in that it is accelerated immediately after the start of rocking, reaches the maximum rocking angular velocity immediately after the rocking starts, and is gradually decelerated after reaching the maximum rocking angular velocity. In order to achieve the above-mentioned object, a semiconductor wafer swing slicing method according to a third aspect of the present invention is characterized in that the inner peripheral blade or the semiconductor material is fed at a moving speed within a range of one-way swing of the semiconductor material. The semiconductor material is gradually decelerated after the start of the swing, is decelerated to the minimum speed immediately before the end of the swing, is accelerated after reaching the minimum speed, and is returned to the speed at the start of the swing at the end of the swing. The oscillating angular velocity is characterized by being accelerated immediately after the oscillating start, reaching the maximum oscillating angular velocity immediately after the oscillating start, and gradually decelerating after reaching the maximum oscillating angular velocity.

[0007]

According to the invention of claim 1, the method of oscillating and slicing a semiconductor wafer according to the present invention, in the range of unidirectional oscillation of the semiconductor material, the inner peripheral blade or the feeding moving speed of the semiconductor material starts the oscillation. After that, the speed is gradually decelerated to the minimum speed immediately before the end of the swing, and after reaching the minimum speed, the speed is accelerated and returned to the speed at the start of the swing at the end of the swing.
The cutting load on the inner peripheral blade becomes uniform.

According to the invention of claim 2, the method of oscillating and slicing a semiconductor wafer according to the present invention, the oscillating angular velocity of the semiconductor material is accelerated immediately after the oscillation is started within the range of the unidirectional oscillation of the semiconductor material. The maximum swing angular velocity is reached immediately after the start of swing, and after reaching the maximum swing angular velocity, the speed is gradually reduced.
The cutting load on the inner peripheral blade becomes uniform. According to the invention of claim 3 of the method of swing slicing a semiconductor wafer according to the present invention, in the range of the one-way swing of the semiconductor material, the inner peripheral blade or the feeding moving speed of the semiconductor material is gradually increased after the swing is started. The speed is decelerated to a minimum speed immediately before the end of the swing, is accelerated after reaching the minimum speed, and returns to the speed at the start of the swing at the end of the swing. The acceleration is performed immediately after the start of the movement, the maximum swing angular velocity is reached immediately after the start of swing, and the maximum swing angular velocity is gradually reduced after the maximum swing angular velocity is reached, so that the cutting load applied to the inner peripheral blade becomes uniform.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of a swing slicing method for a semiconductor wafer according to the present invention will be described in detail below with reference to the accompanying drawings. FIG. 1 shows, as an example, a semiconductor wafer slicing apparatus used when carrying out the semiconductor wafer swing slicing method of the present invention, and the present invention is not limited to this slicing apparatus.

The inner peripheral blade 10 is formed by electrodepositing diamond abrasive grains on the inner peripheral edge of a blade 12 formed in a donut shape. The inner peripheral blade 10 has an outer peripheral edge of a blade 12 pulled up on a chuck body (not shown) and is rotatable in a direction of an arrow A by a rotational force from a spindle (not shown). Further, the inner peripheral blade 10 is held on the movable mount 16 together with the spindle.

The movable mount 16 is movably mounted in the direction of the arrow B along rails 18, 18 arranged in parallel on both sides of the inner peripheral blade 10, and in response to a command signal from the controller 20. It is designed to be driven via a motor (not shown). A work (semiconductor material) 22 is arranged in the inner peripheral blade 10. The work 22 is arranged on a beam member 23 fixed to the main body of the slicing device so as to be rotatable about its axis. That is, the pulley 24 is connected to the upper end portion 22a of the work 22.
5, it is connected to a swing mechanism composed of a belt 26. The motor 25 is fixed to the beam member 23. Further, the motor 25 is driven by the command signal from the control unit 20 described above.

Next, in the semiconductor wafer slicing apparatus constructed as described above, the control unit 20 sends the movable pedestal 16 in the direction of arrow B while the inner peripheral blade 10 is rotated in the direction of arrow A, and the workpiece is moved. The grindstone 14 of the inner peripheral blade 10 is pressed against the blade 22, and the motor 25 is driven to swing the workpiece 22 alternately to the left and right around the axis of the workpiece 22 to cut the workpiece 22. FIG. 2 shows a cutting locus of the semiconductor wafer cut by the semiconductor wafer slicing device shown in FIG. 1, in which the inner peripheral blade 10 is fed and moved in the B direction, and one work 22 is moved.
When it is rocked in the right direction R and cut, it is first cut as a cutting locus R1. Next, when the work 22 is fed and moved in the B direction and is rocked in the left direction L in FIG. 2 to be cut, the work 22 is cut as a cutting locus L1. Similarly, the cutting is performed in the order of R2 → L2 → R3 → L3 ....

FIG. 3 shows the relationship between the cutting amount and the swing position in one swing to the left or right, and FIG. 4 shows the swing position in this one swing and the inner peripheral blade 10 (or workpiece). 22) shows the relationship with the feeding moving speed. If the feeding movement speed is cut at a constant speed in one swing as shown by the two-dot chain line in FIG. 4, immediately before the end of one swing as shown by the two-dot chain line in FIG.
The cutting amount rises sharply. This is as shown in FIG.
Due to the characteristic of cutting the cylindrical body with the curved inner peripheral blade 10, the inner peripheral blade moves in the kerf that has already been cut at the 1-oscillation start position. Due to starting.

As shown by the solid line in FIG. 4, the feeding movement speed of the inner peripheral blade 10 in one swing is gradually reduced after the start of swing and is reduced to the minimum speed immediately before the end of swing,
After reaching the minimum speed, the acceleration is accelerated, and when the swing ends, the speed is controlled to return to the speed at the start of the swing. When the feeding movement speed of the inner peripheral blade 10 is controlled in this way, the peak value of the maximum cutting amount becomes gentle as shown by the solid line in FIG. As a result, the cutting work of the inner peripheral blade 10 becomes uniform, and a sudden load during cutting is not applied, so that the product life of the inner peripheral blade 10 is extended. Further, the warp of the wafer is eliminated and the quality of the cut surface of the wafer is improved.

FIG. 6 shows the cutting amount at one swing position, and FIG. 7 shows the swing angular velocity at one swing position. 2 of FIG.
When the swing angular velocity is constant as shown by the dotted line, the cutting amount sharply increases just before the end of swing, as shown by the solid line in FIG. This is because, as shown in FIG. 5, due to the characteristic of cutting the cylindrical body with the curved inner peripheral blade 10, the inner peripheral blade moves along the already cut kerf at one swing start position, so that the cutting load is almost zero. This is due to the fact that cutting starts from the latter half of one swing.

As shown by the solid line in FIG. 7, the swing angular velocity of the work 22 is accelerated immediately after the swing is started, reaches the maximum swing angular velocity immediately after the swing is started, and gradually increases after reaching the maximum swing angular velocity. When the control is performed so as to reduce the speed to 1, the peak value of the cutting amount becomes gentle as shown by the solid line in FIG. 6, and chipping, warpage, and processing strain do not occur. In the above-described embodiment, the feed movement speed of the inner peripheral blade 10 (or the work 22) and the swing angular velocity of the work 22 in one swing are independently controlled, but the present invention is not limited to this, and the feed movement speed and It may be controlled in combination with the rocking angular velocity.

That is, by combining the feed moving speed and the swing angular velocity, the feed moving speed of the inner peripheral blade 10 or the work 22 is gradually reduced after the start of the swing and reaches the minimum speed immediately before the end of the swing. It is decelerated and accelerated after reaching the minimum speed, and returns to the speed at the start of the swing at the end of the swing, and the swing angular velocity of the work 22 is accelerated immediately after the start of swing and reaches the maximum swing immediately after the start of swing. After reaching the dynamic angular velocity and reaching the maximum swing angular velocity, the speed may be gradually reduced.

[0018]

As described above, according to the swing slicing method for a semiconductor wafer according to the present invention, the cutting load applied to the inner peripheral blade is made uniform, the product life of the inner peripheral blade is improved, and the warp of the wafer is prevented. The quality of the wafer will be improved.

[Brief description of drawings]

FIG. 1 is an explanatory view showing a semiconductor wafer slicing device used for carrying out the present invention.

FIG. 2 is a first example showing a cutting locus of a semiconductor wafer cut by the semiconductor wafer slicing device shown in FIG.

FIG. 3 is an explanatory diagram showing a cutting amount at a swing position.

FIG. 4 is an explanatory view showing the feeding movement speed of the inner peripheral blade at the swing position.

FIG. 5 is an explanatory diagram showing characteristics when a cylindrical body is cut by an inner peripheral blade.

FIG. 6 is an explanatory diagram showing a cutting amount at a swing position.

FIG. 7 is an explanatory diagram showing a swing angular velocity of a work in a swing position.

[Explanation of symbols]

 10 ... Inner peripheral blade 12 ... Blade 16 ... Moving platform 18 ... Rail 20 ... Control unit 22 ... Work 25 ... Motor

Claims (3)

[Claims] 1. A semiconductor wafer is cut by relatively feeding and moving it between a rotating inner blade and a columnar semiconductor material, and swinging the semiconductor material a plurality of times in both directions around an axis thereof. In the swing slicing method of a semiconductor wafer, the feeding movement speed of the inner peripheral blade or the semiconductor material is gradually reduced after the start of the swing within a range of the one-way swing of the semiconductor material, and immediately before the end of the swing. A method of slicing and slicing a semiconductor wafer, comprising decelerating to a minimum speed, accelerating after reaching the minimum speed, and returning to the speed at the start of rocking at the end of rocking. 2. A semiconductor wafer is cut by relatively feeding and moving it between a rotating inner peripheral blade and a columnar semiconductor material, and swinging the semiconductor material a plurality of times in both directions around its axis as a center. In the swing slicing method of a semiconductor wafer, the swing angular velocity of the semiconductor material is accelerated immediately after the start of the swing within the range of the one-way swing of the semiconductor material, and the maximum swing angular velocity immediately after the start of the swing. The method for oscillating slewing of a semiconductor wafer is characterized in that after reaching the maximum swing angular velocity, the maximum slewing angular velocity is gradually reduced. 3. A semiconductor wafer is cut by relatively feeding and moving it between a rotating inner peripheral blade and a columnar semiconductor material, and rocking the semiconductor material a plurality of times in both directions around its axis. In the swing slicing method of a semiconductor wafer according to the above, within a range of the one-way swing of the semiconductor material, the feeding movement speed of the inner peripheral blade or the semiconductor material is gradually reduced after the start of swing and immediately before the end of swing. Is decelerated to the minimum speed, and after reaching the minimum speed, it is accelerated and returns to the speed at the start of the rocking at the end of the rocking, and the rocking angular velocity of the semiconductor material is accelerated immediately after the rocking starts. A swing slicing method for a semiconductor wafer, wherein the maximum swing angular velocity is reached immediately after the start of swing, and after the maximum swing angular velocity is reached, the speed is gradually reduced.