JP2007301688A - Workpiece cutting method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To cut out a workpiece having high flatness by eliminating variation of thickness dimension of the cut workpiece. <P>SOLUTION: A guide plate 3 of a predetermined thickness dimension is temporarily fixed to the cutting start end surface 2a of the workpiece 2, a plurality of grinding tool 1a is press-contacted to the guide plate 3, and cutting of the guide plate 3 is started in the thickness direction. Consecutively, the workpiece 2 is cut in the same direction. At the start of cutting of the guide plate 3, the grinding tool 1a is slid and the respective pitches cause positional deviation. While the guide plate 3 is cut down, the pitch of the grinding tool 1a is gradually returned to the original disposition interval. Around when it comes to the end surface 2a of the cutting start of the workpiece 2, the workpiece is stably cut as the pitch of the grinding tool 1a is at the original disposition interval. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

The present invention relates to a workpiece cutting method for cutting a workpiece made of a rod-shaped material such as a silicon ingot with a grinding tool of a grinding cutter.
Specifically, a plurality of grinding tools arranged at appropriate intervals of a grinding / cutting machine are pressed against the surface of the work material, and the workpieces are bitten by the simultaneous movement of the grinding tools so that a plurality of work pieces are simultaneously processed. The present invention relates to a work cutting method for cutting out each to a predetermined thickness.

  Conventionally, as a workpiece cutting method of this type, a wire saw (wire saw device) in which a plurality of wires are arranged at regular intervals is pressed against a work material (workpiece), and these wires are driven by a drive motor (drive unit). In some cases, the workpiece is cut at a time by reciprocating in the normal and reverse rotations, and a plurality of workpieces are cut into the same thickness dimension (see, for example, Patent Document 1).

Japanese Patent Laid-Open No. 61-265259 (page 3, FIG. 1)

However, in such a conventional work cutting method, even if a plurality of grinding tools are pressed against the work material and brought into contact with each other, the surface of the work material is flat when each grinding tool starts to move. , It is easy to slide in the axial direction of the work material perpendicular to the direction of movement of each grinding tool, thereby causing the pitch of the grinding tool to shift and disturb the spacing, resulting in the cutting of each cut workpiece. There was a problem in that the thickness of the first end portion varied and the flatness of the entire workpiece deteriorated.
In particular, when the grinding / cutting machine is a wire saw and the grinding tool is a wire, the wire itself tends to stretch due to the resistance force generated at the start of cutting. There is a problem that the variation in the thickness dimension appears remarkably as it becomes larger.

The inventions according to claims 1 and 4 of the present invention are intended to eliminate a variation in the thickness dimension of a cut workpiece and cut out a workpiece having a high flatness.
In addition to the object of the invention described in claim 1, the invention described in claim 2 aims to eliminate a workpiece thickness variation due to wire elongation and cut out a workpiece with high flatness. is there.
In addition to the object of the invention described in claim 1 or 2, the invention described in claim 3 aims to eliminate the thickness variation of the cut workpiece with higher accuracy.

In order to achieve the above-described object, the invention according to claim 1 of the present invention is such that a guide plate having a predetermined thickness is temporarily fixed to a cutting start end surface of a work material, and a plurality of grinding tools are attached to the guide plate. The guide plate is pressed to start cutting the guide plate in the thickness direction, and the workpiece is continuously cut in the same direction.
The invention described in claim 2 is characterized in that a configuration in which the grinding and cutting machine is a wire saw is added to the configuration of the invention described in claim 1.
The invention described in claim 3 is characterized in that a structure in which the guide plate is made of the same material as the work material or a material having substantially the same hardness is added to the structure of the invention of claim 1 or 2. .

According to the first aspect of the present invention, a guide plate having a predetermined thickness is temporarily fixed to a cutting start end surface of a work material, and a plurality of grinding tools are pressed against the guide plate, and the guide plate is moved to the guide plate. By starting cutting in the thickness direction and continuously cutting the work material in the same direction, the cutting of the guide plate begins when the grinding tool slides and the respective pitches shift, but the guide plate While cutting, the pitch of the grinding tool gradually returns to the original arrangement interval, and when the workpiece reaches the cutting start end surface, the grinding tool pitch is stably cut at the original arrangement interval. .
Therefore, it is possible to eliminate the variation in the thickness dimension of the cut workpiece and cut out a workpiece with high flatness.
As a result, the cutting dimensional accuracy can be improved and the quality of the cut surface can be improved as compared with the conventional one in which the thickness dimension varies at the cutting start end of the workpiece.

In addition to the effect of the invention of claim 1, the invention of claim 2 is configured such that the pitch is originally adjusted by the tension of the wire as a grinding tool while the guide plate is cut by forming the grinding and cutting machine with a wire saw. By gradually returning to the interval, and reaching the cutting start end face of the work material, the wire is stably cut at the original interval.
Accordingly, it is possible to eliminate the thickness variation of the workpiece due to the elongation of the wire and cut out a workpiece with high flatness.

In addition to the effects of the invention of claim 1 or 2, the invention of claim 3 makes it possible to remove the grinding tool from the guide plate by making the guide plate the same material as the work material or a material having substantially the same hardness. When moving to the cutting material, the cutting interval does not shift due to the hardness difference between the two.
Therefore, the thickness variation of the cut workpiece can be solved with higher accuracy.

  As shown in FIGS. 1 to 4, a workpiece cutting apparatus A directly used for carrying out the workpiece cutting method of the present invention includes a grinding cutter 1 in which a plurality of grinding tools 1 a are arranged at appropriate intervals, and a work material 2. And a guide plate 3 having a predetermined thickness dimension temporarily fixed to the cutting start end surface 2a, and a plurality of grinding tools 1a are simultaneously moved to the surface 3a of the guide plate 3 while being in pressure contact with each other. 3 is started in the thickness direction, and the workpiece 2 is continuously cut in the same direction, so that each grinding tool 1a is bitten into the guide plate 3 and the workpiece 2 at a time. The plurality of workpieces 20 are each cut out to a predetermined thickness.

  The grinding and cutting machine 1 is a slicing machine in which wires, bands, and blades, which are the grinding tools 1a, are arranged at appropriate intervals through a gap of a predetermined interval, such as a multi-wire saw, a multi-band saw, and a multi-blade saw. By moving these grinding tools 1a while being pressed against the work material B, which will be described later, fixed abrasive grains made of a hard material such as diamond, carborundum, alumina, etc. fixed to the tips of the respective grinding tools 1a, or these The thin plate-like workpiece 20 is cut with a slurry containing loose abrasive grains supplied to the pressure contact portion.

  The work material 2 is made of, for example, a silicon ingot or other rod-like material, and a guide plate 3 having a predetermined thickness is bonded to the cut start end surface 2a with an adhesive (not shown) or the like in the radial direction. As a result, the guide plate 3 is temporarily fixed over the entire axial length of the cutting start end surface 2a, and a work holding plate 4 having a predetermined thickness is radially attached to the cutting end end surface 2b with an adhesive (not shown). The workpiece holding plate 4 is temporarily fixed over the entire axial length of the cut end surface 2b.

  The thickness dimension of the guide plate 3 returns to the original arrangement position when the grinding tool 1a which has started to be shifted in the axial direction of the work material 2 cuts the guide plate 3 in the thickness direction. According to the experiment, the length to be obtained needs to be about 1 mm or slightly longer.

  Further, the thickness dimension of the workpiece holding plate 4 is determined by cutting the workpiece holding plate 4 in the thickness direction continuously after the grinding tool 1a cuts the cut end surface 2b of the work material 2. Thus, a length that allows the work material 2 to be completely separated into the thin plate-like workpiece 20 is required.

  Further, at least the guide plate 3 of the guide plate 3 and the workpiece holding plate 4 is preferably made of the same material as the work material 2 or made of a material having substantially the same hardness as the work material 2.

Then, after the work material 2 is cut into a plurality of workpieces 20 by the grinding tool 1a of the grinding and cutting machine 1, a release agent is supplied, or heating or cooling is performed to reduce the adhesive strength of the adhesive. For example, the guide plate 3 and the work holding plate 4 are removed from each workpiece 20.
Embodiments of the present invention will be described below with reference to the drawings.

In the first embodiment, as shown in FIGS. 1 and 2, the work material 2 is a cylindrical body such as a silicon ingot, and the grinding and cutting machine 1 serves as the grinding tool 1a in the axial direction of the work material 2 or the like. A plurality of thin plates are processed at a time by bringing a plurality of wires arranged at intervals into pressure contact with the surface of the cylindrical work material B, and causing the work material 2 to bite by simultaneous movement of these wires 1a. The case where it is a multi-wire saw which cuts out the thing 20 (wafer) is shown.
Is.

  In this multi-wire saw 1, a wire 1a is wound around a plurality of rollers 1b, 1c, 1d arranged in parallel, and one of these rollers 1b, 1c, 1d is used as a drive motor (not shown). Thus, the plurality of wires 1a are reciprocated in the radial direction of the cylindrical work material B by rotating forward and backward.

  Then, by moving one or both of the plurality of wires 1a laid across the rollers 1b, 1c, and 1d and the columnar workpiece B relatively close to each other, the workpiece B Each wire 1a is brought into pressure contact with the surface 3a of the guide plate 3 temporarily fixed to the cutting start end surface 2a, and is sliced in the radial direction to be cut and separated into a thin plate-like workpiece 20.

  In the case of the illustrated example, the multi-wire saw 1 winds the wire 1a in an inverted triangle shape across three rollers 1b, 1c, 1d arranged in parallel, and rotates the lower driving roller 1b forward and backward. The cylindrical work material 2 is pressed down from the upper side of the wire 1a, which is horizontally mounted across the driven rollers 1c, 1d.

  As another example, although not shown, a wire is wound in a triangular shape across three rollers arranged in parallel to rotate the upper drive roller forward and backward, and to the two lower driven rollers. It is also possible to push up a cylindrical work material from below and to press-contact a plurality of wires laid horizontally almost horizontally.

  Furthermore, the work material 2 is temporarily fixed to the work holding plate 4 with an orientation flat cut out on one side surface of the work material 2 as a cut end end surface 2b, and is disposed on the opposite side of the cut end end surface 2b in the radial direction. A guide plate 3 is temporarily fixed to a cutting start end surface 2a having an arcuate cross section.

Next, the operation of the workpiece cutting method A and the workpiece cutting apparatus A directly used for the operation and the operation and effects thereof will be described.
First, in a state where the wires of the grinding tool 1a are in pressure contact with the surface 3a of the guide plate 3 temporarily fixed to the cutting start end surface 2a of the work material 2, the wires are rotated by the rotation of the driving roller 1b of the multi-wire saw 1. When cutting is started by simultaneously moving the la, since the surface 3a of the guide plate 3 is flat when each wire 1a starts to move, the work material 2 and the guide plate 3 orthogonal to the moving direction of each wire 1a. It is easy to slide in the axial direction of the wire, and to oscillate sideways, whereby the pitch of the wire 1a is displaced and the interval is easily disturbed.

  For this reason, as shown by the solid line in FIG. 2, the cutting start position of each wire 1a with respect to the surface 3a of the guide plate 3 is displaced in the axial direction of the guide plate 3 and the work material 2, and these wires 1a Even if the pitch of the wire 1a is disturbed from the original arrangement interval, as each wire 1a cuts the guide plate 3, the pitch of these wires 1a gradually returns to the original arrangement interval, and the cutting of the workpiece 2 Around the beginning end surface 2a, the pitch of the wire 1a is stably cut with the original arrangement interval.

  According to the experiment, when the work material 2 is a silicon ingot and the guide plate 3 is made of the same material silicon, if each wire 1a is cut by about 1 mm from the surface of the guide plate 3, the wire 1a It was confirmed that the pitch gradually returned to the original arrangement interval.

Then, after these wires 1a are cut into the cutting start end surface 2a of the work material 2, they are cut to the cutting end end surface 2b and continuously to the workpiece holding plate 4 in the same manner as the conventional workpiece cutting method. By cutting a predetermined dimension, as shown by the two-dot chain line in FIG. 2, the thin plate-like workpiece 20 is completely cut and separated, and the workpiece 20 is connected and held by the workpiece holding plate 4 while being cut and separated. .
After that, if necessary, it is possible to remove the guide plate 3 and the work holding plate 4 by cleaning dirt remaining in the workpiece 20 such as chips and slurries containing flow-off abrasive grains, or fixed abrasive grains that have fallen off. In this case, the cutting process is completed.

  As a result, each workpiece 20 that has undergone such a cutting process has no variation in thickness dimension at the cutting start end portion, and improves the flatness of the entire workpiece 20, thereby improving the flatness. The high workpiece 20 can be cut out.

  In particular, in this embodiment, the grinding and cutting machine 1 is a wire saw, and the wire that is the grinding tool 1a is easily stretched by the resistance force generated at the start of cutting, so that the cutting of the flat surface 3a of the guide plate 3 starts. The horizontal runout tends to increase.

  However, when the work cutting method of the present invention is used, while the guide plate 3 is cut, the pitch gradually returns to the original interval due to the tension of each wire 1a, so that the cutting start end surface 2a of the workpiece 2 is cut. Since the wire 1a is stably cut at the original interval, the advantage of eliminating the thickness variation of the workpiece 20 due to the elongation of the wire 1a and cutting out the workpiece 20 with high flatness. is there.

  Further, if the guide plate 3 is made of the same material as that of the work material 2 or made of a material having substantially the same hardness, when the wire 1a moves from the guide plate 3 to the work material 2, the cutting interval is positioned due to the difference in hardness between the two. There is no deviation, so that variations in the thickness of the workpiece 20 can be eliminated with higher accuracy.

  In the second embodiment, as shown in FIG. 3, the work material 2 is a completely cylindrical member having no orientation flat, and a guide plate 3 having a predetermined thickness dimension is formed on the cut start end surface 2 a having an arcuate cross section. The embodiment shown in FIG. 1 and FIG. 2 is a configuration in which a workpiece holding plate 4 having a predetermined thickness is temporarily fixed to an arcuate cut end face 2b disposed on the opposite side in the radial direction. Unlike the first embodiment, the other configuration is the same as that of the first embodiment shown in FIGS.

  Therefore, the second embodiment shown in FIG. 3 can obtain the same effects as the first embodiment described above.

  In the third embodiment, as shown in FIG. 4, a guide plate 3 having a predetermined thickness is temporarily fixed using an orientation flat notched on one side surface of the work material 2 as a cutting start end surface 2a, and opposite to the radial direction. Unlike the first embodiment shown in FIGS. 1 and 2, the configuration in which the workpiece holding plate 4 having a predetermined thickness is temporarily fixed to the arcuate cut end surface 2b disposed on the side is different from the first embodiment shown in FIGS. This is the same as the first embodiment shown in FIGS.

  Therefore, the third embodiment shown in FIG. 4 can obtain the same operational effects as the first embodiment described above.

In the previous embodiment, the grinding / cutting machine 1 is a multi-wire saw that moves a plurality of wires as the grinding tool 1a. However, the present invention is not limited to this, and the multi-wire saw has a structure other than the illustrated example. Alternatively, a slicing machine having another structure such as a multi-band saw or a multi-blade saw may be used instead of the multi-wire saw.
In these cases, the same effects as those described above can be obtained.

It is a perspective view of the workpiece | work cutting method which shows Example 1 of this invention. It is a vertical side view which expands and shows a cutting start part. It is a perspective view of the workpiece | work cutting method which shows Example 2 of this invention. It is a perspective view of the workpiece | work cutting method which shows Example 3 of this invention.

Explanation of symbols

A Work cutting device 1 Grinding and cutting machine 1a Grinding tool (wire) 2 Work material 2a Cutting end face 2b Cutting end face 3 Guide plate 3a Surface 4 Work holding plate 20 Workpiece

Claims (3)

A plurality of grinding tools (1a) arranged at appropriate intervals of the grinding / cutting machine (1) are pressed against the surface of the work material (2), and the work material (2 In the workpiece cutting method of cutting a plurality of workpieces (20) into a predetermined thickness at a time,
A guide plate (3) having a predetermined thickness is temporarily fixed to the cutting start end surface (2a) of the work material (2), and a plurality of grinding tools (1a) are pressed against the guide plate (3), A work cutting method characterized by starting cutting the guide plate (3) in the thickness direction and continuously cutting the work material (2) in the same direction. The work cutting method according to claim 1, wherein the grinding and cutting machine (1) is a wire saw. The work cutting method according to claim 1 or 2, wherein the guide plate (3) is made of the same material as the work material (2) or made of a material having substantially the same hardness.

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