JP6617721B2 - Ingot cutting device - Google Patents

Description

  The present invention relates to an ingot cutting device.

  As shown in FIG. 5, a silicon ingot 50 manufactured by the Czochralski method (CZ method) or the like has a cone-shaped end portion (top portion 52 and tail portion 53) on a cylindrical body portion 51. Yes. In general, in the processing of a silicon ingot, as shown in FIG. 6A, after the outer peripheral surface of the body portion 51 is ground to have a predetermined diameter by a cylindrical grinding device or the like, as shown in FIG. The cone-shaped end portions (the top portion 52 and the tail portion 53) are separated to form only the cylindrical body portion 51, and the body portion 51 is cut into a plurality of blocks as necessary. Next, processing for making the block into a wafer is performed.

  When cutting a cone-shaped end of an ingot or cutting a body part into a plurality of blocks, an inner peripheral blade slicer, an outer peripheral blade slicer, etc. are used. Along with this, many band saws have been used. In a general band saw cutting device, for example, as described in Patent Document 1, an ingot placed on a cutting table is cut while running an endless belt-like blade stretched between pulleys. By feeding, the ingot can be cut. More specifically, in the ingot cutting device 101 as shown in FIG. 7A, the ingot W is placed in the V-shaped groove 103 of the cutting table 102, and the blade 104 is moved relative to the ingot W. The ingot W can be cut by moving and cutting and feeding. Further, at this time, the ingot W may be pressed and held from above by the body upper holder 105 and then cut.

  In the cutting of the silicon ingot, the cone-shaped end portion is cut off to form only a cylindrical body portion, and the body portion is cut into a plurality of blocks as necessary, and then a predetermined diameter is obtained by a cylindrical grinding device or the like. The outer peripheral surface may be ground.

JP 2009-154346 A JP 2011-20411 A JP 2010-267941 A

As shown in FIG. 5, before grinding the outer peripheral surface, the cone-shaped end is cut off to form only a cylindrical body, and when the body is cut into a plurality of blocks as necessary, an ingot is used. The outer peripheral surface has an uneven shape. Accordingly, as shown in FIG. 7B, which is a cross-sectional view seen from the Z direction in FIG. 7A, when the ingot W having an uneven outer peripheral surface is placed in the V-shaped groove 103, the groove 103 Many portions are not in contact with the outer surface of the body portion of the ingot W. In such a case, cutting is started by the blade 104 in a state where the body portion of the ingot W is held by the body upper holder 105, but the body portion W _{1 to} be cut out and left uncut immediately after the cutting is completed. body part W ₂ resulting in a fine movement. In addition, fine movement is likely to occur due to the increase in the diameter and weight of the ingot corresponding to the increase in the diameter of the wafer. Based on past experience, if at least one of the body part W _{1 to} be cut out and the body part W _{2 to} be left uncut is finely moved by 0.1 mm or more, a large chipping (chip) exceeding 1 mm occurs, resulting in a decrease in product yield. There was a problem that.

  For example, Patent Documents 2 and 3 disclose cutting techniques for suppressing the occurrence of chipping. The technique of patent document 2 is a technique which installs the shock absorbing material (urethane resin) from which hardness differs in the lower part of the trunk | drum part cut out and the trunk | drum part left uncut. The weights of the body part to be cut out and the body part to be left uncut differ depending on the respective lengths. Further, even if the length of the body part to be cut out and the body part to be left uncut are the same, the weight difference between the body part to be cut out and the body part to be left uncut increases as the diameter becomes larger. In other words, in the buffer material having a certain hardness, the amount of buffering (the amount of sinking) changes every moment depending on the weight of the body part to be cut out and the body part to be left uncut. The body part to be cut off and the body part to be cut off are slightly moved.

  Moreover, in patent document 3, enclosing a granular material in V process pad, mounting the ingot with an uneven | corrugated outer peripheral surface on V process pad of a cutting machine, and discharging the air in V process pad outside This is a technology to harden the granular material. In this technique, the granular material is cured by discharging air to the outside, but the granular material itself is not cured by bonding and fusion. Therefore, in a large-diameter, high-weight ingot, fine movement of about 0.1 mm between the body part cut out immediately before the completion of cutting and the body part left uncut is easily generated.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to provide an ingot cutting device that can suppress fine movement of an ingot and suppress occurrence of chipping in the cutting of an ingot.

  In order to achieve the above object, the present invention comprises a cutting table having a V-shaped groove on the upper surface, and an ingot placed horizontally in the groove, and a blade for cutting the ingot. An ingot cutting device for cutting the ingot by sending the blade from the upper side to the lower side relative to the ingot, wherein the upper part of the body presses the ingot placed in the V-shaped groove from above A holding tool, further disposed in a storage hole provided in the V-shaped groove, and capable of moving up and down in the depth direction of the storage hole; and disposed on an upper end of the shaft; The body lower part holding which has the front-end | tip part which can be closely_contact | adhered to the outer peripheral surface of the said ingot mounted in the said groove | channel by raising, and the shaft lock part which can fix the said shaft A plurality of body upper holders, pressing the ingots placed in the grooves from above, and the outer ends of the ingots placed in the grooves at the tips of the lower body holders An ingot cutting device is provided that cuts the ingot with the blade while fixing the ingot by contacting the surface from below and fixing the shaft.

  In this way, with the fuselage upper holder that presses the ingot from above, by fixing the shaft with the tips of the plurality of fuselage lower holders in close contact with the ingot from below, the fuselage and cutting residue that are cut out just before cutting is completed Can suppress the fine movement of the body portion, and can suppress the occurrence of chipping and a step in the cut surface. In particular, even if the outer peripheral surface of the ingot is, for example, an uneven shape, the ingot can be securely fixed according to the outer peripheral shape by a plurality of lower body holders, and even an ingot of high weight and large diameter Can be fixed securely. As mentioned above, if it is the ingot cutting device of this invention, the fall of a product yield can be suppressed.

  At this time, it is preferable that the shaft can be moved up and down by air pressure, and the shaft lock portion can contact and fix the shaft by elastic deformation by hydraulic pressure.

  In the present invention, the fuselage lower holder can be configured as described above, and can be easily controlled to move up and down by air pressure, and the shaft can be firmly fixed by hydraulic pressure.

  At this time, it is preferable that a plurality of the lower body holders are provided in a range of 20 mm to 450 mm from the cutting position of the ingot.

  The closer the body lower holder is to the cutting position, the more effectively the fine movement of the ingot can be suppressed. However, if the body lower holder is installed at a position 20 mm or more away from the cutting position of the ingot, the lower body holder Can be reliably prevented from contacting the blade. Moreover, if the trunk lower holder is installed at a distance of 450 mm or less from the cutting position, it is possible to sufficiently suppress the fine movement of the ingot.

  If it is the ingot cutting device of this invention, in the cutting | disconnection of an ingot, it can suppress a fine movement of an ingot and can suppress generation | occurrence | production of the chipping and the level | step difference of a cut surface. As a result, cutting defects are reduced, stable product quality can be maintained, and reduction in product yield can be suppressed.

It is the schematic which showed an example of the ingot cutting device of this invention, (a) Front view, (b) Side view. It is the schematic which showed an example of the trunk | drum lower holder in the ingot cutting device of this invention. It is sectional drawing seen from the Z direction of Fig.1 (a). It is a figure which shows an example of the installation space | interval of the trunk | drum lower holder in the ingot cutting device of this invention. It is the schematic of a common silicon ingot. (A) is the schematic of the silicon ingot after cylindrical grinding, (b) is the schematic of the silicon ingot after cutting. It is the schematic which showed an example of the conventional ingot cutting device, (a) Front view, (b) It is sectional drawing seen from the Z direction.

  Hereinafter, although an embodiment is described about the present invention, the present invention is not limited to this.

  As described above, the conventional ingot cutting apparatus has a problem that the body part cut out just before the cutting is completed and the body part left uncut are slightly moved, thereby causing chipping and reducing the product yield. It was. For example, fine movement of the body portion has occurred due to cutting of an ingot having an uneven outer peripheral surface such as an Azgron ingot pulled up by the Czochralski method (CZ method) or the like.

  Therefore, the present inventor has intensively studied to solve such problems. As a result, it is possible to suppress the fine movement of the body part regardless of the shape of the outer peripheral surface of the ingot by pressing the ingot with the upper body holder from above and fixing the plurality of lower body holders from below. As a result, the present invention has been completed. Hereinafter, the configuration of the ingot cutting device of the present invention will be described more specifically.

  FIG. 1 is a schematic view showing an example of an ingot cutting device 1 according to the present invention, where (a) is a front view and (b) is a side view. As shown in FIG. 1, the ingot cutting device 1 of the present invention has a V-shaped groove 3 on the upper surface, and a cutting table 2 on which the ingot W is placed horizontally in the groove 3 and the ingot W. And a blade 4 for the purpose. In this ingot cutting device 1, the ingot W is cut by sending the blade 4 from the upper side to the lower side relative to the ingot W. In this case, the ingot W and the cutting table 2 may be raised toward the blade 4, or the blade 4 may be lowered toward the ingot W and the cutting table 2. Further, a band saw or the like may be used as the blade 4, but the present invention is not limited to this, and can be applied to an outer peripheral blade cutting device, an inner peripheral blade cutting device, and the like. Further, examples of the ingot to be cut include a silicon single crystal, but the ingot to be cut in the present invention is not limited to this, and a compound single crystal such as GaP or GaAs, a crystal such as an oxide or a nitride is used. It can be applied to other ingots that require precision cutting.

  The ingot cutting device 1 according to the present invention includes a trunk upper holder 5 that presses the ingot W placed in the V-shaped groove 3 from above. Further, as shown in FIG. 1A, the ingot cutting device 1 of the present invention has a depth of the storage hole 10 as shown in FIG. A shaft 7 that can move up and down in the vertical direction, a tip 8 that is disposed at the upper end of the shaft 7 and that can be in close contact with the outer peripheral surface of the ingot W placed in the groove 3 by raising the shaft 7; A plurality of lower body holders 6 having a shaft lock portion 9 to which the shaft 7 can be fixed are provided. The plurality of lower trunk holders 6 may be disposed on both of the two slopes of the V-shaped groove 3 as shown in FIG. The tip 8 that contacts the ingot W is preferably made of a material that does not damage or contaminate the ingot W. For example, the tip 8 is preferably made of resin.

  As shown in FIG. 3 which is a cross-sectional view seen from the Z direction in FIG. 1A, such an ingot cutting device 1 according to the present invention has an ingot W placed in the groove 3 by the body upper holder 5. While pressing down from above, the tips 8 of the plurality of lower body holders 6 are brought into close contact with the outer peripheral surface of the ingot W placed in the groove 3 from below, and the shaft 7 is fixed by the shaft lock 9. While fixing the ingot W, the ingot W is cut with the blade 4. The ingot W may be fixed by pressing the ingot W from above with the trunk upper holder 5 and then bringing the respective distal end portions 8 of the plurality of trunk lower holders 6 into close contact with the outer peripheral surface of the ingot W from below. 3 is a cross-sectional view seen from the Z direction of FIG. 1A, only one of the contact surfaces of the ingot W and the V-shaped groove 3 is shown. The outer peripheral surface of the ingot W and the tip 8 are also in close contact with each other on the contact surface opposite to the one.

As described above, the ingot W is fixed to the groove 3 by fixing the shaft 7 by bringing the tip 8 of the plurality of lower body holders 6 into close contact with the ingot W from below together with the upper body holder 5 for pressing the ingot W from above. Therefore, it is possible to complete the cutting without slightly moving the body part W _{1 to} be cut out and the body part W ₂ to be left uncut immediately before the cutting is completed. Can be suppressed. Further, in particular, even if the outer peripheral surface of the ingot W is uneven as shown in FIG. 3, the ingot can be reliably fixed according to the outer peripheral shape by the plurality of lower body holders 6, Even large ingots can be fixed securely. As a result, the ingot cutting device 1 of the present invention can suppress a decrease in product yield.

  Further, as shown in FIG. 2, the shaft 7 can be moved up and down by air pressure, and the shaft lock portion 9 is preferably capable of contacting and fixing the shaft 7 by elastic deformation by hydraulic pressure. In this way, the up-and-down movement can be easily controlled by the air pressure, and the shaft can be locked more firmly by the hydraulic pressure. Since the shaft lock portion 9 is elastically deformed by hydraulic pressure, it is desirable to use brass or the like for the elastic deformation portion. Since the shaft 7 is fixed by the shaft lock portion 9, a high-strength material such as carbon steel or stainless steel is used. It is desirable to use In addition, for example, an air cylinder or the like can be used to move the shaft 7 up and down by air pressure.

In addition, it is desirable to adjust the air pressure according to the number of the trunk lower holders 6 installed. In particular, the shaft lifting power for adhering the distal end portion 8 to the body portion W ₁ to be cut out of the ingot W is across multiple lower torso holder 6, about one-fifth of the weight of the body W ₁ to be cut out If the air pressure is such that the effect of suppressing fine movement is further improved.

Moreover, it is preferable that the trunk | drum lower holder 6 is provided with two or more in the range of 20 mm or more and 450 mm or less from the cutting position of the ingot W. The fuselage lower holder 6 can more effectively suppress the fine movement of the ingot W as it is closer to the cutting position. However, if the fuselage lower holder 6 is installed at a position 20 mm or more away from the cutting position of the ingot W, the lower part of the fuselage Contact between the holder 6 and the blade 4 can be reliably prevented. Moreover, if the trunk | drum lower holder 6 is installed in the distance of 450 mm or less from a cutting position, the fine movement of the ingot W can fully be suppressed. Further, as shown in FIG. 4, the gap between the fuselage lower holder 6 and the blade 4 is set to about 20 mm on both sides of the fuselage part W ₁ cut out around the blade 4 and the fuselage part W ₂ left uncut, and the fuselage lower holder It is preferable that the distance between 6 is set at an interval of about 100 mm from the blade 4 (cutting position) to a position within 450 mm. If the fuselage lower holder 6 is arranged at such an interval, the effect of suppressing the fine movement of the ingot W is further improved.

  EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples and comparative examples of the present invention, but the present invention is not limited to the examples.

(Example)
Using the ingot cutting device of the present invention, a silicon single crystal ingot was cut, and the occurrence rate of large chipping exceeding 1 mm was calculated.

  More specifically, a total of 10 pieces are installed on the V-shaped cutting table on the side from which the lower body holder is cut out, at a position 20 mm, 120 mm, 220 mm, 320 mm, 420 mm away from the blade (band saw). In addition, on the V-shaped cutting table on the side to be left uncut, the same number of positions and number of lower body holders as those on the side to be cut out were installed. Then, 200 blocks were cut from a silicon single crystal ingot having a diameter of 200 mm and an outer peripheral surface having a concavo-convex shape so that the maximum length of the cut block was 450 mm. At the time of cutting, the ingot placed on the groove is pressed from above by the upper fuselage holder, and the shaft is fixed after the tips of the lower fuselage holders are brought into close contact with the outer peripheral surface of the ingot from below. Then, the ingot was fixed.

  It should be noted that the total shaft lifting force of the body lower holder on the block side to be cut out was set so as not to be larger than the weight of the block to be cut out. Specifically, as shown in Table 1 below, the maximum support weight per fuselage lower holder is calculated according to the length of the block to be cut out, and the maximum support weight per fuselage lower holder is calculated. The air pressure was adjusted to 3.29 kg which was the smallest value among the maximum supported weights. Further, the air pressure was adjusted so that the shaft lifting force per one block-side fuselage lower holder left to be cut was 3.29 kg which was the same as the block-side fuselage lower holder shaft lifting force to be cut out.

(Comparative example)
The ingot was cut under the same conditions as in the example, except that the ingot was cut using a conventional ingot cutting device in which urethane rubber was bonded to a V-shaped groove as a cushioning material without installing the lower body holder. The occurrence rate of cutting and chipping was calculated.

  As a result, in the example, large chipping exceeding 1 mm occurred in only 5 blocks out of 200 blocks, and the chipping rate was 2.5%, and the occurrence of chipping was drastically reduced as compared with the comparative example. That is, the product yield can be greatly improved. On the other hand, in the comparative example, large chipping exceeding 1 mm occurred in 195 blocks out of 200 blocks, and the chipping occurrence rate was 97.5%. Thus, in the comparative example, the product yield was significantly deteriorated as compared with the example.

  The present invention is not limited to the above embodiment. The above-described embodiment is an exemplification, and the present invention has any configuration that has substantially the same configuration as the technical idea described in the claims of the present invention and that exhibits the same effects. Are included in the technical scope.

DESCRIPTION OF SYMBOLS 1 ... Ingot cutting device, 2 ... Cutting table, 3 ... V-shaped groove | channel,
4 ... Blade, 5 ... Upper body holder, 6 ... Lower body holder,
7 ... shaft, 8 ... tip, 9 ... shaft lock, 10 ... housing hole,
W ... Ingot, W ₁ ... Body part cut out, W ₂ ... Body part left uncut.

Claims (3)

A cutting table having a V-shaped groove on the upper surface, and an ingot horizontally placed in the groove; and a blade for cutting the ingot, the blade being relatively positioned with respect to the ingot An ingot cutting device for cutting the ingot by sending it downward from above,
A fuselage upper holder for pressing the ingot placed in the V-shaped groove from above;
A shaft disposed in the storage hole provided in the V-shaped groove and movable up and down in the depth direction of the storage hole, and disposed at the upper end of the shaft. A plurality of lower body holders having a tip portion that can be in close contact with the outer peripheral surface of the ingot placed from below and a shaft lock portion that can fix the shaft;
The ingot placed on the groove is pressed from above by the upper fuselage holder, and the tip of each of the lower fuselage holders is in close contact with the outer peripheral surface of the ingot placed on the groove from below. The ingot cutting device characterized in that the ingot is cut by the blade while fixing the ingot by fixing the shaft.   The ingot cutting device according to claim 1, wherein the shaft can be moved up and down by air pressure, and the shaft lock portion can contact and fix the shaft by elastic deformation by hydraulic pressure.   3. The ingot cutting device according to claim 1, wherein a plurality of the lower body holders are provided in a range of 20 mm to 450 mm from a cutting position of the ingot. 4.

Images