JP6455294B2 - Wire saw equipment - Google Patents

Description

  The present invention relates to a wire saw device for cutting a workpiece into a wafer shape.

  Conventionally, a wire saw is known as means for cutting a wafer from a semiconductor ingot. In the wire saw apparatus, a plurality of cutting wires are wound around a plurality of wire guides to form a wire row, the cutting wires are driven at high speed in the axial direction, and free abrasives such as silicon carbide are used. The workpiece is cut and fed to the wire row while a slurry containing grains is appropriately supplied, so that the workpiece is simultaneously cut to each wire position.

  More specifically, a slice base that covers substantially the entire axial direction is fixed to a part of the workpiece in the circumferential direction, and the entire workpiece is cut and fed in a state where the slice base is held by the workpiece holder. Is cut with a cutting wire. At this time, a method of pressing the workpiece against the wire row is known by a method of pressing the workpiece against the wire row from above and a method of pressing from below. However, in cutting a semiconductor silicon ingot, The method of pressing from above is the mainstream.

  Recently, instead of supplying slurry containing loose abrasive grains, a method of cutting while supplying only coolant using a wire having diamond abrasive grains fixed on the wire surface is also used. Hereinafter, a method of supplying a slurry containing free abrasive grains is called a free abrasive grain system, and a method using a wire in which diamond abrasive grains are fixed on the wire surface is called a fixed abrasive grain system.

Here, FIG. 6 shows an outline of an example of a general wire saw device.
The wire saw device 101 includes a wire 103 for cutting the workpiece 102, a plurality of wire guides 104 wound with the wire 103, wire tension applying mechanisms 105 and 105a for applying tension to the wire 103, and a workpiece 102 to be cut. A workpiece feeding mechanism 106 that holds and feeds the workpiece downward and a nozzle 107 that supplies coolant or slurry at the time of cutting are provided.

  The machining fluid supply mechanism 108 includes a nozzle 107, a tank 109, a chiller 110, and the like. The nozzle 107 is disposed above the wire row 103a. The nozzle 107 is connected to a tank 109, and coolant or slurry is stirred in the tank 109, adjusted in temperature by a chiller 110, and then supplied from the nozzle 107 to the wire 103. At this time, the machining liquid is uniformly supplied to each wire 103 of the wire row 103a. Then, the coolant or slurry rides on the wire row 103 a and is sent to the cutting portion of the workpiece 102. Thereafter, the supplied coolant or slurry is returned to the tank 109 and recycled.

  The wire 103 is fed out from one wire reel 111 and enters a wire guide 104 through a traverser 112 and a wire tension applying mechanism 105 including a torque motor 113 and the like. The wire 103 is wound about 300 to 400 times around the wire guide 104 and travels in the axial direction. After forming the wire row 103a, the wire 103 passes through another wire tension applying mechanism 105a including a torque motor 113a and a traverser 112a. It is wound around a wire reel 111a.

  When the workpiece 102 is cut in such a wire saw device 101, an end material in which the workpiece is cracked or chipped is generated. Such end material may be dragged by the wire 103 and enter the groove of the wire guide 104. When the end material enters the groove of the wire guide 104, not only is the wire guide 104 damaged or the wire 103 is derailed from the groove, but in the worst case, the wire 103 is disconnected and the workpiece 102 is cut. May not be able to continue.

  For such a problem, as disclosed in Patent Document 1, for example, an end material prevention plate is installed between the workpiece and the wire guide with a gap between the upper end of the end material prevention plate and the wire. Thus, the end material is prevented from being caught in the wire guide.

JP 2000-61799 A

  However, even when the end material preventing plate as shown in Patent Document 1 is used, the effect of preventing the end material generated from the work from being caught in the wire guide is not sufficient. Therefore, the end material of the workpiece may enter the groove portion of the wire guide, the wire guide may be damaged, the wire may be derailed from the groove, and the wire may be disconnected.

  Here, the wire traveling speed at the time of cutting the workpiece is about 900 m / min at the maximum in the case of the loose abrasive method. On the other hand, in the case of the fixed abrasive method, the maximum speed may be 1500 m / min or higher. Thus, the traveling speed of the wire is faster in the fixed abrasive method than in the free abrasive method. Therefore, in the fixed abrasive method, the frequency at which the end material is dragged by the wire and wound into the wire guide is higher than that in the free abrasive method.

  In the case of the loose abrasive system, the end material that has entered the wire guide groove is worn away by a slurry containing loose abrasive grains between the wire and the wire guide groove. On the other hand, in the case of the fixed abrasive method, since the abrasive grains are present only on a part of the wire, the end material that has entered the wire guide groove exists in the wire guide groove for a long time. Therefore, in the case of the fixed abrasive method, the wire where there is no abrasive is worn, and therefore the frequency of wire breakage is particularly high, which is a problem.

  The present invention has been made in view of the above-described problems, and an object thereof is to provide a wire saw device that can prevent an end material generated at a cutting portion of a work from being caught in a wire guide.

In order to achieve the above object, according to the present invention, a wire row formed by wires wound around a plurality of wire guides and reciprocating in an axial direction, a nozzle for supplying coolant or slurry to the wires, A workpiece feeding mechanism that presses the held workpiece against the wire row, and presses the workpiece held by the workpiece feeding mechanism against the wire row while supplying the coolant or the slurry to the wire from the nozzle; A wire saw device for cutting the workpiece into a wafer by cutting and feeding,
An end material preventing plate is disposed between the workpiece and the wire guide, the end material preventing plate has a groove-shaped notch through which the wire passes, and an upper end of the end material preventing plate is the wire row. Provided is a wire saw device in which the end material preventing plate is disposed so as to be positioned above.

  If it is such, when the wire passes through the notch portion of the end material prevention plate, the end material is generated at the work cutting portion and attached to the wire and dragged to the position of the end material prevention plate. Can be scraped off. Therefore, it can prevent that an end material is caught in a wire guide. Thereby, it is possible to prevent the wire guide from being damaged, the wire from being derailed, and the wire from being broken. On the other hand, the coolant or slurry adhering to the surface of the wire is not scraped off by the notch portion of the end material preventing plate. Therefore, it is possible to prevent the wire from being disconnected due to the wire to which no coolant or slurry is attached cutting the workpiece.

At this time, at least one nozzle is provided on each of the left and right sides when viewed from the cut surface direction of the workpiece,
Of the nozzles, it is preferable that at least one of the left and right sides as viewed from the cut surface direction of the workpiece is disposed between the workpiece and the end material preventing plate.

  If it is such, since a coolant or slurry can be supplied to the wire after passing through the notch portion of the end material prevention plate, the coolant or slurry can be sufficiently supplied to the workpiece cutting portion. . Therefore, it is possible to more reliably prevent the wire from being disconnected due to the wire to which no coolant or slurry is attached cutting the workpiece.

  Further, at this time, it is preferable that an end material receiver capable of recovering the end material separated from the workpiece is disposed below the end material preventing plate.

  If it is such, it can prevent that the end material detached | separated from the workpiece | work or the end material scraped off by the end material prevention board falls below, and contacts the wire row | line | wire which runs on a lower surface.

  In the wire saw device of the present invention, when the wire passes through the notch portion of the end material preventing plate, the end generated at the cutting portion of the work and attached to the wire and dragged to the position of the end material preventing plate. The material can be scraped off. Therefore, it can prevent that an end material is caught in a wire guide. Thereby, it is possible to prevent the wire guide from being damaged, the wire from being derailed, and the wire from being broken. On the other hand, the coolant or slurry adhering to the surface of the wire is not scraped off by the notch portion of the end material preventing plate. Therefore, it is possible to prevent problems such as disconnection of the wire caused by the wire to which no coolant or slurry is attached cutting the workpiece.

It is the schematic which showed an example of the wire saw apparatus of this invention. It is the schematic which showed an example of the notch part of the end material prevention board arrange | positioned at the wire saw apparatus of this invention. It is the schematic which showed an example of the arrangement position of a nozzle in the wire saw apparatus of this invention. It is the schematic which showed another example of the end material prevention board arrange | positioned at the wire saw apparatus of this invention. It is the schematic which showed the end material prevention board used in a comparative example. It is the schematic which showed the general wire saw apparatus.

Hereinafter, although an embodiment is described about the present invention, the present invention is not limited to this.
As mentioned above, the end material generated at the cutting part of the workpiece penetrates into the groove of the wire guide, the wire guide is damaged, the wire is derailed from the groove, and in the worst case There was a problem that the wire was broken and the cutting of the workpiece could not be continued.

  Therefore, the present inventor has intensively studied to solve such problems. As a result, if the upper end of the end material prevention plate that is disposed between the workpiece and the wire guide and has a groove-shaped notch through which the wire passes is located above the wire row, It has been found that the end material detached from the workpiece can be prevented from being wound around the wire guide. And the best form for implementing these was scrutinized and the present invention was completed.

  As shown in FIG. 1, a wire saw device 1 of the present invention includes a wire 3 for cutting a workpiece 2, a plurality of wire guides 4 around which the wire 3 is wound, and a wire tension applying mechanism for applying tension to the wire 3. 5, 5a, holding the workpiece 2 to be cut, pressing the held workpiece 2 against the wire row 3a and cutting and feeding the workpiece 2, the workpiece feeding mechanism 6 capable of cutting the workpiece 2 into a wafer shape, A nozzle 7 for supplying coolant or slurry at the time of cutting is provided.

  The machining fluid supply mechanism 8 includes a nozzle 7, a tank 9, a chiller 10, and the like. The nozzle 7 is disposed above the wire row 3a. The nozzle 7 is connected to a tank 9, and coolant or slurry is stirred in the tank 9, adjusted in temperature by a chiller 10, and then supplied from the nozzle 7 to the wire 3. At this time, the processing liquid is uniformly supplied to each wire 3 of the wire row 3a. Then, the coolant or the slurry rides on the wire row 3 a and is sent to the cutting portion of the workpiece 2. Thereafter, the supplied coolant or slurry is returned to the tank 9 and recycled.

  The wire 3 is fed out from one wire reel 11 and enters a wire guide 4 via a traverser 12 via a wire tension applying mechanism 5 including a torque motor 13 and a dancer roller (dead weight) (not shown). The wire 3 is wound around the wire guide 4 about 300 to 400 times and travels in the axial direction to form a wire row 3a, and then passes through another wire tension applying mechanism 5a including a torque motor 13a and a traverser 12a. It is wound around a wire reel 11a.

  The present invention can be suitably applied to either the above-described free abrasive method or fixed abrasive method. As described above, in the conventional fixed abrasive method, it is particularly preferable to apply the present invention because the frequency at which the end material is dragged onto the wire and wound into the wire guide is higher than that in the free abrasive method.

  In the wire saw device 1, an end material preventing plate 14 is disposed between the workpiece 2 and the wire guide 4. As shown in FIG. 2, the end material preventing plate 14 has a groove-shaped notch 15 through which the wire 3 passes. And as shown in FIG. 3, the end material prevention board 14 is arrange | positioned so that the upper end of the end material prevention board 14 may be located above the wire row | line | column 3a.

  If it is such, it will generate | occur | produce in the cutting part of the workpiece | work 2 when the wire 3 passes the notch part 15 of the end material prevention board 14, will adhere to the wire 3, and will reach to the position of the end material prevention board 14 The scraps that have been dragged can be scraped off. Therefore, it is possible to prevent the end material from entering the groove of the wire guide 4. Thereby, it is possible to prevent the wire guide from being damaged, the wire from being derailed, and the wire from being broken. On the other hand, the coolant or slurry adhering to the surface of the wire 3 is not scraped off by the notch 15 of the end material preventing plate 14. Therefore, it is possible to prevent the wire 3 from being disconnected due to the wire 3 to which no coolant or slurry is attached cutting the workpiece 2.

  The shape of the notch 15 may be a groove shape through which the wire 3 can pass. For example, as shown in FIG. 2, the notch 15 can be U-shaped.

  At this time, as shown in FIG. 3, at least one nozzle 7 is provided on each of the left and right sides as viewed from the cut surface direction of the work 2, and at least one of the nozzles 7 as viewed from the cut surface direction of the work 2. It is preferable that the books are respectively arranged between the workpiece 2 and the end material preventing plate 14.

  If it is such, since coolant or slurry can be supplied to the wire 3 after passing through the notch 15 of the end material preventing plate 14, coolant or slurry is sufficiently supplied to the cut part of the work 2. can do. Therefore, disconnection of the wire 3 caused by the wire 3 to which no coolant or slurry is attached cuts the workpiece 2 can be more reliably prevented.

  Specifically, for example, as shown in FIG. 3, two nozzles 7 are provided on each of the left and right sides when viewed from the cutting surface direction of the workpiece 2, and the nozzle 7 is viewed from the cutting surface direction of the workpiece 2. Each of the left and right ones may be disposed between the workpiece 2 and the end material preventing plate 14.

  At this time, it is preferable that the end material receiver 16 capable of collecting the end material separated from the workpiece 2 is disposed below the end material preventing plate 14.

  If this is the case, it is possible to prevent the end material detached from the workpiece 2 or the end material scraped off by the end material preventing plate 14 from falling downward and coming into contact with the wire row 3a traveling on the lower surface. it can.

  In FIG. 1, an end material receiver 16 is disposed below the end material preventing plate 14 to form an upward U-shaped shape. If it is such a shape, since a coolant or slurry will flow downward from the part used as opening, the collection | recovery will become easy. Further, for example, a hole for collecting coolant or slurry may be provided in the end material receiver 16.

  Further, the present invention is not limited to this. For example, as shown in FIG. 4, the end material receiver 16 may be disposed below the end material preventing plate 14 so as to have a box shape with an upper surface opened. At this time, for example, a hole for collecting coolant or slurry may be provided in the end material receiver 16.

  As described above, the end material receiver 16 can be integrated with the end material prevention plate 14, for example. In addition, this invention is not limited to this, It is good also as a structure which can be divided | segmented into the part of the end material receptacle 16 and the part of the end material prevention board 14. FIG.

  The notch 15 is preferably formed on the end material prevention plate 14 in accordance with the wire pitch and the wire diameter of the wire row 3 a used in the wire saw device 1. For example, it can be formed by a wire saw device to be used. In the case of forming with a wire saw device, for example, it can be produced by the following procedure.

First, a member for forming a notch is prepared. The member that forms the notch is preferably made of stainless steel, and preferably has a structure that can be divided from the end material receiver disposed in the lower part thereof.
And if the member which forms a notch part is fixed to the workpiece holding part of a workpiece | work feeding mechanism and it presses to a wire row | line | column similarly to cut | disconnecting a workpiece | work, a notch part can be formed. At this time, if the notch is formed using a wire having a diameter larger than that used when actually cutting the workpiece, the notch of the end material prevention plate contacts the wire in subsequent workpiece cutting. This is preferable because it can be prevented.
If it is such a method, an end material prevention board can be manufactured easily.

  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 these.

(Example)
Using the wire saw device 1 of the present invention as shown in FIG. 1, the work 2 that is a silicon ingot having a diameter of 300 mm was cut a plurality of times.

  As shown in FIG. 3, the wire saw device 1 includes an end material preventing plate 14 having a groove-shaped notch 15 (see FIG. 2) through which the wire 3 passes between the workpiece 2 and the wire guide 4. Has been. The end material preventing plate 14 used was an end material receiving plate 16 disposed below. The end material prevention plate 14 and the end material receiver 16 were made of stainless steel. And the end material prevention board 14 was arrange | positioned so that the upper end of the end material prevention board 14 may be located 20 mm above the wire row | line | column 3a. The diameter of the wire 3 used for cutting is 140 μm, and the deflection amount of the wire 3 downward during cutting of the workpiece is about 10 mm at the maximum. Therefore, in order to prevent the end material preventing plate 14 and the wire 3 from contacting each other, The dimensions of the notch 15 were 240 μm wide and 40 mm deep.

  Further, two nozzles 7 are provided on each of the left and right sides when viewed from the cut surface direction of the work 2, and one of the nozzles 7 on the left and right sides when viewed from the cut surface direction of the work 2 is used to prevent the workpiece 2 and the end material. It was assumed that they were respectively arranged between the plates 14.

  As the wire 3, a wire having diamond abrasive grains fixed on the surface thereof was used. Then, the workpiece 2 was cut while only the coolant was supplied from the nozzle 7.

Then, when the workpiece 2 was cut, the number of times the wire 3 was broken was measured, and the value divided by the total number of the cut workpieces 2 was taken as the wire breakage rate.
As a result, the wire breakage rate in the examples was as low as 1/5 or less compared to the comparative example.

(Comparative example)
In the conventional wire saw device 101 as shown in FIG. 6, as shown in FIG. 5, an end material preventing plate 114 is provided between the workpiece 102 and the wire guide 104, and the upper end of the end material preventing plate 114 is connected to the wire 103. On the other hand, it arrange | positioned through the clearance gap. As the end material preventing plate 114, one having an end material receiver 116 disposed at the lower part thereof was used. Then, two nozzles 107 are arranged between the end material preventing plate 114 and the wire guide 104 in the left-right direction as viewed from the cut surface direction of the workpiece 102. Except for using such a wire saw device, a plurality of workpieces 102, which are silicon ingots having a diameter of 300 mm, were cut in the same manner as in the example.

  And the wire disconnection rate was calculated | required like the Example.

  As a result, the wire breakage rate in the comparative example was higher than that in the example. When the wire breaks, the workpiece cannot be continuously cut. For this reason, there are major disadvantages such as a significant deterioration in production efficiency. Therefore, it is preferable not to deteriorate the wire breakage rate, and a smaller one is desirable.

  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 ... Wire saw apparatus, 2 ... Workpiece, 3 ... Wire, 3a ... Wire row | line | column,
4 ... Wire guide, 5, 5a ... Wire tension applying mechanism, 6 ... Work feeding mechanism,
7 ... Nozzle, 8 ... Working fluid supply mechanism, 9 ... Tank, 10 ... Chiller,
11, 11a ... wire reel, 12, 12a ... traverser,
13, 13a ... Torque motor, 14 ... End material prevention plate, 15 ... Notch,
16 ... End material receptacle.

Claims (2)

A wire row formed by wires wound around a plurality of wire guides and reciprocating in the axial direction, a nozzle for supplying coolant or slurry to the wire, and a work feeding mechanism for pressing a held work against the wire row The workpiece is cut into a wafer by pressing and feeding the workpiece held by the workpiece feeding mechanism to the wire row while supplying the coolant or the slurry to the wire from the nozzle. A wire saw device,
An end material preventing plate is disposed between the workpiece and the wire guide, the end material preventing plate has a groove-shaped notch through which the wire passes, and an upper end of the end material preventing plate is the wire row. The end material prevention plate is disposed so as to be located above the upper side,
Comprising at least two nozzles on each of the left and right sides as viewed from the cutting plane direction of the workpiece;
Among the nozzles, at least one each of the left and right viewed from the cutting plane direction of the workpiece is disposed between the workpiece and the end material preventing plate, and at least one is the end material preventing plate. all SANYO respectively disposed between the wire guide of the vertex portion,
It said groove-like cutouts wire saw device according to claim der Rukoto which scrape scraps.   The wire saw device according to claim 1, wherein an end material receiver capable of collecting the end material separated from the workpiece is disposed below the end material prevention plate.

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