JP2000218510A - Fixed abrasive grain wire saw - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce waviness of a cut surface by preliminarily providing grooved roller units having a different space between grooved roller shafts, and performing cutting after the selection of grooved roller unit according to the size of an object to be cut. SOLUTION: A plurality of grooved roller units 70 are provided preliminarily and used selectively properly. Each of the units 70 has a different shaft-shaft space A corresponding to the diameter of an ingot 32 and composed of three grooved rollers 18A, 18B, 18C and grooved roller retaining brackets 72A, 72B retaining the three grooved rollers 18A, 18B, 18C. In the case that the space A between the rollers 18A, 18B is unnecessarily longer than the diameter DG of the ingot 32, for example, wires 14 in wire lines are vibrated with resistance, vibration, or jetted working liquid at the time of cutting, and thereby the wire pitch in the wire lines is not stabilized, resulting in increase in waviness on a surface of a wafer cut surface. Accordingly, cutting is carried out with the grooved roller unit 70 having the minimum space A with respect to the diameter DG of the ingot upon cutting.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fixed abrasive wire saw, and more particularly to a fixed abrasive wire saw for cutting brittle materials such as silicon, glass, and ceramics.

[0002]

2. Description of the Related Art FIG. 9 is a perspective view showing a structure of a cutting portion of a conventional wire saw. According to the figure, a wire 114 is wound around the outer circumference of groove rollers 118 having a plurality of grooves, and a wire row 120 having a wire pitch Wp is formed.
Is formed.

[0003] In the cutting section of the wire saw configured as described above, reciprocating traveling of the wire array 120 is performed at high speed. Then, a processing liquid containing free abrasive grains is supplied from a nozzle (not shown) provided near the wire row 120 to the wire row 120.
Then, the ingot 132 is pressed against the wire row 120 while being sprayed toward the ingot 132 as a workpiece. Then, the ingot 132 is cut into a number of wafers having a thickness thinner than the width of the wire pitch Wp by the lapping effect of the free abrasive grains.

[0004] One of the factors that increase the amount of undulation on the cut surface of the wafer is considered to be a factor due to a change in the wire pitch Wp of the wire array. Wire pitch Wp
In order to stabilize the tension, it is conceivable to increase the tension of the wire 114, but there is a limit to the tension to be set for physical reasons such as the tensile strength of the wire 114 and the fatigue limit of repeated bending. In recent years, the diameter of the ingot 132 has tended to increase in diameter for reasons of productivity improvement, and the demand for the flatness of the cut wafer has also been increasing for the purpose of improving the degree of integration of elements to be manufactured. Demands for cutting are also increasing.

[0005]

In the conventional wire saw, the axial distance between the groove rollers around which the wire rows are wound cannot be changed according to the size of the workpiece. Therefore, when a small workpiece with a short cutting length is cut with a wire saw with a long groove roller shaft interval produced on the assumption that the workpiece with a long cutting length is cut, the axial interval of the wire row becomes unnecessarily large. Due to the long influence, the wire pitch Wp of the wire row used for cutting was apt to fluctuate, the undulation amount of the cut surface of the workpiece was large, and the cutting accuracy was poor.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a fixed abrasive wire saw capable of obtaining a good cut surface by reducing the amount of undulation of the cut surface of a workpiece. Aim.

[0007]

According to the present invention, in order to achieve the above object, a wire with fixed abrasive grains is wound around a plurality of groove rollers to form a wire array, and the wire is run and the wire array is formed. In a fixed abrasive wire saw that cuts a large number of wafers by pressing a workpiece against a cutting portion of the workpiece, the groove roller shaft interval is provided in advance with a plurality of different groove roller units, and in accordance with the size of the workpiece to be cut. A groove roller unit is provided which is capable of selecting and cutting a groove roller unit or adjusting a shaft interval of the groove roller in accordance with a size of a workpiece to be cut.

According to the present invention, since the axial distance between the groove rollers can be changed in accordance with the size of the workpiece, the fixed abrasive is intended for cutting a workpiece having a long cutting length. Even when a small workpiece with a short cutting length is cut using a wire saw, the amount of undulation of the cut surface does not increase, and a good cut surface can be obtained.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of a fixed abrasive wire saw according to the present invention will be described below in detail with reference to the accompanying drawings. FIG. 1 is a perspective view showing an entire configuration of a fixed abrasive wire saw 10 according to a first embodiment of the present invention.

As shown in FIG. 1, a wire 14 with fixed abrasive grains wound on a wire reel 12 passes through a wire running path formed by a large number of guide rollers 16, 16,. , 18B, 18C to form a horizontal wire row 20. The wire 14 having the wire row 20 formed thereon is wound on a wire reel (not shown) via a wire running path on the other side formed symmetrically with respect to the wire row 20.

A large number of grooves are formed at a constant pitch on the outer circumference of the groove rollers 18A to 18C, and a wire row 20 is formed by sequentially winding the wires 14 around these grooves. A wire guide device 22, a dancer roller 24, and a wire cleaning device 26 are provided on each of the wire running paths formed on both sides of the wire row 20 (only one side is shown), and the wire guide device 22 is a wire reel. The wire 14 is guided from 12 at a constant pitch. The dancer roller 24 is provided with a weight (not shown) having a predetermined weight, and applies a constant tension to the traveling wire 14 with the weight. The wire cleaning device 26 sprays a cleaning liquid onto the running wire 14 to remove cutting powder of the workpiece and the processing liquid 52 attached to the wire 14 from the wire 14.

The pair of wire reels 12, 12 and the groove roller 18C are respectively connected to motors (not shown) that can rotate forward and reverse, and the wire 14
By driving the motor, the motor reciprocates between the pair of wire reels 12 at high speed. The wire row 20
A work feed table 28 that moves vertically with respect to the wire row 20 is installed above. The work feed table 28 is provided with a tilting unit 30, and the ingot 32 is held by a work holder extending downward from a lower portion of the tilting unit 30. The tilting unit 30 holds the ingot 32 so as to be tiltable in the horizontal direction and the vertical direction.
The crystal orientation of the ingot 32 is aligned.

A working fluid tank 34 is provided below the fixed abrasive wire saw 10, and a working fluid 52 is stored therein. The processing liquid 52 in the processing liquid tank 34 is pumped up by a pump (not shown) and supplied to a processing liquid nozzle (not shown) installed near the wire row 20 via a pipe (not shown). Injected into row 20. An oil pan 36 is provided below the wire row 20 to collect the working fluid 52 jetted to the wire row 20 and send it to the working fluid tank 34 again.

While the ingot 32 is being cut, processing heat is generated by the cutting process, and the temperature of the processing liquid 52 rises. Therefore, the fixed abrasive wire saw 10 is provided with a heat exchanger 38 for the working fluid 52 to stabilize the temperature of the working fluid 52. The processing liquid 52 in the processing liquid tank 34 is circulated and supplied to the heat exchanger 38 to exchange heat. FIG. 2 shows a groove roller unit 70 used in the first embodiment.
Are three groove rollers 18A, 18B, 18C,
Groove roller holding brackets 72A and 72B holding these three groove rollers are provided. The groove roller holding brackets 72A, 72B
Are screwed to the base 76 of the fixed abrasive wire saw 10 by mounting bolts 74, 74,....

According to the present invention, the diameter D of the ingot 32
A plurality of groove roller units 70 having different axial intervals A according to G are prepared in advance, and are appropriately selected and used.
For example, when the axial interval A between the groove rollers 18A and 18B is longer than necessary with respect to the diameter DG of the ingot 32, the cutting resistance and vibration at the time of cutting, the vibration, and the jetted working fluid 52 cause the wire 14 of the wire row 20 to be cut. Due to the vibration, the wire pitch Wp of the wire row 20 is not stabilized, and the amount of undulation on the surface of the cut surface of the wafer increases. Therefore, the cutting is performed by using the groove roller unit 70 having the axial interval A between the groove rollers 18A and 18B which is the smallest with respect to the diameter DG of the ingot 32.

The procedure for replacing the groove roller unit 70 is as follows. First, after all the wires 14 are wound around the wire reel 12, the bolts 74 are removed to remove the groove roller unit 70. Next, a groove roller unit 70 to be used is prepared and mounted on the gantry 76. The groove roller 18 is brought into contact with the reference surface 78 of the gantry 76 and the groove roller holding bracket 72A.
A, 18B and the fixed abrasive wire saw 10 are aligned. The groove roller holding brackets 72A, 72B and the gantry 76 are screwed together with the bolts 74, 74,... While maintaining a secure alignment.

Next, the wire 14 is unwound from the wire reel 12, passed through a wire guide device 22, a guide roller 16, a dancer roller 24, guide rollers 16, 16,... And wound around groove rollers 18A, 18B, 18C. Preparation for cutting the workpiece is started again through the wire 14 to the wire reel 12 on the opposite side. The fixed-abrasive wire saw 10 configured as described above drives a motor (not shown) to drive the wire reels 12 and 12 and the groove rollers 18.
C is rotated at high speed, and the wire 14 reciprocates at high speed. The work feed table 28 descends while spraying the working fluid 52 from the working fluid nozzle (not shown) onto the traveling wire row 20, and the groove rollers 18 </ b> A to 18 </ b>
Ingot 3 against wire row 20 wound around C
Press 2. At this time, the working liquid 52 sufficiently adheres to the traveling wire 14 with the fixed abrasive, and the ingot 32
Is efficiently cut into a large number of wafers by the effect of a lubricant or a penetrant contained in the processing liquid 52.

FIG. 3 shows a fixed abrasive wire saw 1 according to the present invention.
0 is a diagram showing a second embodiment of the present invention. FIG. According to the figure, the groove roller shaft interval adjusting means includes a gantry 86, groove roller holding brackets 82A to 82D movably supported in the Y direction with respect to the gantry 86, and the gantry 86.
, For screwing the groove roller holding brackets 82A to 82D, and tap holes 88, 88,.

As shown in FIG. 3, the means for changing the supporting position of the groove roller holding brackets 82A to 82D with respect to the gantry 86 changes the tap holes 88 for screwing the bolts 74, 74,. Means or means for adjusting the supporting position by processing the mounting holes of the bolts 74 provided in the groove roller holding brackets 82A to 82D into elliptical long holes.

In the first embodiment shown in FIG. 2, the groove roller unit 70 is changed in accordance with the groove roller shaft interval A.
However, in the second embodiment shown in FIG. 3, since the three groove rollers 18A to 18C are independently supported by the gantry 86 of the fixed abrasive wire saw 10, the groove roller holding bracket 82A The groove roller shaft interval A can be adjusted by moving ~ 82D in the Y direction shown in Fig. 3 and supporting it on the gantry.

Although not shown in FIG. 3, in order to adjust the positions of the groove roller holding brackets 82A to 82D, the tip of the rotatably supported adjusting screw is attached to the groove roller holding bracket 82A formed with a female screw.
To the groove roller holding brackets 82A to 82D by rotating the adjusting screw.
Is provided, the adjustment of the set position is facilitated.

Further, the adjusting screw is supported by a supporting member of the adjusting screw having a female screw formed thereon, and a tip portion of the adjusting screw is abutted against the groove roller holding brackets 82A to 82D to rotate the adjusting screw. Even if a fine movement mechanism configured to move the groove roller holding brackets 82A to 82D is provided, it is easy to adjust the set positions of the groove roller holding brackets 82A to 82D. At this time, in order to keep the groove roller holding brackets 82A to 82D in constant contact with the abutted adjusting screw, an elastic member such as a spring may be used for pressing.

FIG. 4 shows a fixed abrasive wire saw 1 according to the present invention.
0 is a side view showing a third embodiment of the present invention. According to the figure, the groove roller shaft interval adjusting means is supported movably along the groove rollers 18A, 18B, rails 96, 96 of a guide device such as a linear guide, and the rails 96, 96 of the guide device. Sliders 94, 94, spindle brackets 90, 90 to which the sliders 94, 94 are attached, and a ball screw 98 as a feed mechanism.
And a motor 100 that is the power of the ball screw 98. Although not shown, nuts for ball screws 98 are formed inside the spindle brackets 90, 90.

According to the groove roller shaft interval adjusting means constructed as described above, when the shaft of the motor 100 rotates, the ball screw 98 rotates, and the spindle brackets 90, 90 on which the nuts of the ball screw 98 are formed are guided by the guide device. Along the rails 96, 96, the groove rollers 18A and 18B move in opposite directions, and the axial distance A changes continuously.

Although not shown in FIG. 4, an axial spacing adjusting means for continuously varying the axial spacing A of the groove rollers 18A, 18B is provided on the end face on the opposite side of the groove rollers 18A, 18B. I have. FIG. 5 is a side view showing a fourth embodiment of the fixed abrasive wire saw 10 according to the present invention.

According to FIG. 5, the shaft interval adjusting means includes a groove roller holding bracket 102, a pin bearing 104 attached to the groove roller holding bracket 102,
104, arms 106, 106 rotatably supported on the pin bearings, and the arms 106, 106
Groove rollers 18A, 1 rotatably supported with respect to
8B, ball screws 98, 98, the ball screws 98,
Motors 100, 100, which are motive power for rotating 98,
The ball screws 98, 98 are rotatably supported on the arms 106, 106 and rotate the ball screws 98, 98.
And 106 for converting the rotation of the nut 106 into rotation.

When changing the shaft interval A, the motor 10
The shafts 0, 100 are rotated in opposite directions to rotate the ball screws 98, 98. Then arm 10
Nuts 108, 10 rotatably supported by 6, 106
8 moves on ball screws 98, 98. One end of the ball screws 98, 98 is
2 so that the arms 106, 10
6 rotates about the pin bearings 104, 104. Then, since the groove rollers 18A and 18B move toward the opposite sides, the axial interval A (mm) between the groove rollers 18A and 18B can be changed.

That is, in the example of FIG.
Although an example in which a guide device such as a linear guide is used to adjust the axial interval A between 8A and 18B has been described, in the example of FIG. 5, the groove rollers 18A and 18B have a structure that rotates around a fulcrum. Although not shown in FIG. 5, the shaft interval adjusting means for continuously changing the shaft interval A of the groove rollers 18A and 18B is a groove roller 18A,
It is also provided on the opposite end face of 18B.

FIG. 6 shows a fixed abrasive wire saw 1 according to the present invention.
FIG. 11 is a side view showing a fifth embodiment of the present invention. The shaft interval adjusting means shown in FIG.
12, spindle brackets 110, 110 for the groove rollers 18A, 18B, and the spindle bracket 1
The sliders 114, 114,... Of the guide devices such as linear guides attached to the guide plates 10, 110, the rails 116, 116,. 6 includes a ball screw 98 that moves in the vertical direction in FIG. 6, bearings 122 that support the rotation of the ball screw 98, and a motor 100 that is a power for rotating the ball screw 98.

The moving plate 120 is provided with a nut (not shown) of a ball screw 98 serving as a feed mechanism. The moving plate 120 moves in the vertical direction in the figure by rotating the ball screw 98. The movement of the spindle brackets 120 causes the spindle brackets 110, 110 to move in opposite directions to each other.
Can be changed.

That is, in the example of FIG.
In the example in which the rails of the guide device and the ball screws 98, 98 are provided in parallel to adjust the axial interval A of the shafts 8A, 18B, in the example of FIG. 98
And a shaft gap adjusting means provided with a moving plate 120 between them. The shaft interval adjusting means thus configured is characterized in that the support rigidity of the groove rollers 18A and 18B is high.

According to the above-described groove roller shaft interval adjusting means, it is possible to change the axial interval of the groove rollers even when the fixed abrasive wire saw is being cut as well as when the fixed abrasive wire saw is stopped. . Although not shown in FIG. 6, an axial interval adjusting means for continuously varying the axial interval A of the groove rollers 18A, 18B is provided also on the end face on the opposite side of the groove rollers 18A, 18B.

FIGS. 7A to 7C show the relationship between the cutting length of the ingot 32 and the axial distance between the groove rollers during cutting. FIG. 7A shows the wire 14 wound around three groove rollers 18A to 18C, the diameter DR of the groove rollers 18A and 18B, the clearance a between the groove rollers 18A and 18B, and the groove roller 18A. , 18B and the ingot 32
Of the ingot 32, the feed amount Z of the ingot 32, and the clearance a of the groove rollers 18A and 18B.

FIG. 7 shows the state immediately after the start of cutting, so that the groove roller shaft interval A1 is short. If the groove roller shaft interval A1 is short, the wire pitch Wp of the wire row is stable, so that the cutting accuracy is good. FIG. 7 (B)
Indicates a state in which the cutting proceeds and the ingot 32 is sent in the Z direction. The groove roller shaft interval A2 is determined by the cutting feed amount Z and the diameter DR of the groove rollers 18A and 18B.
And the diameter DG of the ingot 32 and the groove roller 18
A, 18B and the clearance a between the ingot 32 are determined as a function.

FIG. 7C shows a state in which the cutting progresses and the ingot 32 is further fed in the Z direction. The groove roller shaft interval A3 is equal to the groove roller 18A, 18B.
, The diameter DG of the ingot 32, and the clearance a between the groove rollers 18A, 18B and the ingot 32. As described above, by setting the groove roller shaft interval A to the minimum length necessary for cutting, the cut surface undulation of the ingot 32 can be suppressed to the minimum.

FIG. 8 is a graph showing an example of the relationship between the groove roller shaft interval A (mm) and the feed amount Z (mm) of the ingot 32 shown in FIGS. 7A and 7B. It is. According to the figure, the feed amount Z (mm) takes a constant value A = a0 + DR from 0 (mm) to Z1 (mm), and then increases and the constant value of A = 2 * a + DR + DG after Z = Z2. It has become. In the present invention, the groove roller shaft interval A (mm) and the feed amount Z of the ingot 32 shown in FIG.
The present invention is not limited to the relationship with (mm), and the object of the present invention is achieved if the groove roller shaft interval A (mm) takes a form expressed as a function of the feed amount Z (mm). Can be.

In the above description, the present invention is applied to the case where the present invention is applied to a fixed abrasive wire saw. However, the present invention can also be applied to a conventional loose abrasive wire saw.

[0038]

As described above, according to the present invention, the axial distance between the groove rollers can be changed according to the size of the workpiece, so that the undulation amount of the cut surface of the workpiece can be reduced. A good cut surface can be obtained without increasing the size.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an entire configuration of a fixed abrasive wire saw according to a first embodiment of the present invention.

FIG. 2 is a side view showing the first embodiment of the fixed abrasive wire saw according to the present invention.

FIG. 3 is a side view showing a second embodiment of the fixed abrasive wire saw according to the present invention.

FIG. 4 is a side view showing a third embodiment of the fixed abrasive wire saw according to the present invention.

FIG. 5 is a side view showing a fourth embodiment of the fixed abrasive wire saw according to the present invention.

FIG. 6 is a side view showing a fifth embodiment of the fixed abrasive wire saw according to the present invention.

FIGS. 7A, 7B, and 7C are views showing the relationship between the cutting length of an ingot and the axial distance of a groove roller during cutting of the fixed abrasive wire saw according to the present invention.

FIG. 8 is a diagram showing a relationship between a groove roller shaft interval A (mm) shown in FIGS. 7A to 7C and an ingot feed amount Z (mm).

FIG. 9 is a perspective view showing a structure of a cutting portion of a conventional wire saw.

[Explanation of symbols]

10: fixed abrasive wire saw, 14: wire, 18A-1
8C: groove roller, 20: wire row, 32: ingot, 70: groove roller unit, 98 ball screw

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 3C058 AA05 AA09 AA13 AA14 AA18 AB08 BA07 BC02 CA01 CB01 DA03 3C069 AA01 BA06 BB03 CA04 EA02

Claims (2)

[Claims] 1. A wire having fixed abrasive grains is wound around a plurality of groove rollers to form a wire row, and the wire is run and a workpiece is pressed against a cut portion of the wire row to form a large number of wafers. In the fixed abrasive wire saw, a plurality of groove roller units having different groove roller shaft intervals are provided in advance, and the groove roller unit is selected and cut according to the size of the workpiece to be cut. Wire saw with abrasive. 2. A plurality of wafers formed by winding a wire with fixed abrasive grains around a plurality of groove rollers to form a wire row, running the wire and pressing a workpiece against a cut portion of the wire row. A fixed-abrasive wire saw for cutting into a plurality of groove rollers according to the size of a workpiece to be cut; Grained wire saw.