JPH11179645A - Groove roller for wire saw - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simplify operation, so that dynamic balance of a groove roller can be adjusted, and attain the improvement of flatness of a wafer and reduction of a rate of occurrence of a wire break in cutting ingot. SOLUTION: In the case of adjusting dynamic balance of each groove roller 12, along an annular guide groove 51, a pair of balance weights 50, on an outer surface of an end plate part 40a of each sleeve end plate 40, are turned clockwise or counterclockwise, to be balanced, so that by simple operation, dynamic balance of the groove roller 12 can be adjusted. In this way, the improvement of flatness of a wafer and reduction of a rate of occurrence of a wire break in cutting ingot are attained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a grooved roller for a wire saw, and more particularly, to adjust the dynamic balance of the grooved roller by a simple operation, thereby improving the flatness of a wafer and generating a wire break when cutting an ingot. The present invention relates to a groove roller for a wire saw capable of reducing the rate.

[0002]

2. Description of the Related Art In a wire saw, a wire for cutting an ingot derived from a pay-out bobbin (or a reel) is wound around a plurality of groove rollers in a coil shape and then wound on a winding bobbin. The device configuration is as follows. Therefore, for example, when cutting an ingot such as single crystal silicon, loose abrasive (hereinafter, referred to as lapping oil)
(In some cases simply referred to as abrasive grains) while continuously supplying a predetermined amount of a slurry-like abrasive liquid to the ingot, while relatively pressing one ingot against the reciprocating wire row, the abrasive action of the abrasive grains causes A book ingot is cut into many wafers. Specifically, when the wire train reciprocates, the free abrasive grains in the abrasive liquid are shaved while being pressed against the bottom of the cut groove of the ingot by each wire. The groove roller is formed by lining a base metal with urethane rubber having a predetermined thickness, and engraving a roller groove on the outer peripheral surface of the urethane rubber.

[0003]

By the way, the groove roller of the wire saw is usually removed from the wire saw at regular intervals in consideration of deformation and wear of the groove shape due to use, and the outer peripheral surface is ground or cut. And a new roller groove is carved. This roller groove is engraved on the outer peripheral surface of the urethane rubber lining. By repeating the cutting, the thickness of the urethane rubber is reduced, and the dynamic balance of the entire groove roller is easily lost. When the thickness becomes less than a predetermined thickness, the base metal is used to remove the urethane rubber of the lining, and the lining is re-lined to remove a damage such as a tapered portion. When this situation is repeated, there is a disadvantage that the balance gradually loses even if the dynamic balance is initially obtained.

As described above, in the groove roller, since the outer peripheral surface of the steel base metal is lined with urethane rubber having a predetermined thickness, the accuracy of the base metal is improved, but the lining of this lining is considered. Little consideration was given to the dynamic balance, which is likely to be out of order due to thickness unevenness. As a result, each time each groove roller is refurbished, axial vibration occurs on its rotating shaft. Therefore, during operation of the wire saw, a phenomenon that the wire is locally pulled or loosened between the groove rollers has occurred. Therefore, the flatness of the obtained wafer is deteriorated, and the wire is overloaded, so that the wire may be broken. In addition, such a phenomenon has become remarkable in today when the reciprocating speed of the wire was 100 m / min and the speed was increased to 500 to 1000 m / min.

[0005] The inventors of the present invention have conducted intensive studies and as a result, if a balance weight is attached to the end face of the groove roller in advance so as to be movable, it is only necessary to move the balance weight in a predetermined direction within the end face of the groove roller. The present inventors have found that the dynamic balance of the groove roller can be easily achieved, and completed the present invention.

[0006]

SUMMARY OF THE INVENTION The present invention is directed to a wire saw for adjusting the dynamic balance of a groove roller by a simple operation, thereby improving the flatness of a wafer and reducing the incidence of wire breakage when cutting an ingot. The aim is to provide a grooved roller. In addition, the present invention
It is an object of the present invention to provide a wire saw groove roller that can be easily adjusted in balance. In addition, the present invention
It is an object of the present invention to provide a wire saw groove roller capable of easily performing fine balance adjustment.

[0007]

According to the present invention, there is provided a wire saw for cutting one ingot into a plurality of wafers, wherein the wire saw is provided with a groove roller for winding a wire in a coil shape. The wire saw groove roller has a balance weight movable on an end surface of the wire saw groove roller via balance weight moving means.

The wire saw to which the present invention is applied may be of any type. For example, the ingot may be moved to press and contact the wire row for cutting, or conversely, the wire row may be moved to press and contact the ingot to cut. Further, the lower surface of the ingot may be in contact with the upper portion of the wire array, or the upper surface of the ingot may be pressed against the lower portion of the wire array. The abrasive used for cutting includes, for example, an average particle size of 1
A well-known material including abrasive grains such as SiC of 0 to 50 μm can be used. Examples of the ingot cut by the wire saw include a silicon single crystal, a compound semiconductor single crystal, a magnetic material, quartz, and ceramics.

The balance weight moving means here is not limited as long as it can move the balance weight in a predetermined direction on one or both end faces of the groove roller. For example, guide grooves or guide ridges for moving the balance weight may be arranged on the end surface of the groove roller in an elliptical arrangement, a polygon arrangement, or an arbitrary curved shape. The balance weight only needs to have an appropriate weight, and its shape, size and the like are arbitrary. Alternatively, a number of weight fitting portions and weight engaging portions may be provided on the entire end surface of the groove roller, and the balance weight may be fixed to any of them. The balance weight may be moved manually by an operator, or may be moved automatically using a drive source.

According to a second aspect of the present invention, the balance weight moving means has an annular slide groove arranged in a perfect circle around a center point of an end face of the groove roller.
2. The wire saw groove roller according to claim 1, wherein said balance weight is provided movably along said annular slide groove. In the case of such a slide groove, in order to prevent the moving balance weight from being separated or displaced by the rotation of the groove roller, for example, the groove shape may be a wedge-shaped cross section, a dovetail groove, or a stopper for fixing the balance weight to a position. You may fix with various fixing tools, such as a screw. This is the same in the invention of claim 3.

According to a third aspect of the present invention, the balance weight moving means has a linear slide groove extending radially about a center point of the roller end face, and the balance weight is provided with a linear slide groove. The wire roller for a wire saw according to claim 1, wherein the groove roller is provided movably along the groove. The number of linear slide grooves is one, two,
Any number of three, four, five or more may be used. At least one balance weight is arranged in each linear slide groove.

A fourth aspect of the present invention is the groove roller for a wire saw according to any one of the first to third aspects, wherein a plurality of the balance weights are used. The number of balance weights used may be two, three, four, five or more. Finer balance adjustment can be performed as the number of balance weights used increases.

[0013]

According to the present invention, when adjusting the dynamic balance of each groove roller, the balance weight is moved on the end face of the groove roller by the balance weight moving means to achieve the dynamic balance. Therefore, the dynamic balance of the groove roller can be adjusted by a simple operation. As a result, the flatness of the wafer is improved, and the incidence of wire breakage during ingot cutting is reduced.

According to the second aspect of the present invention, when the balance of the groove roller is adjusted, the balance weight is formed into a perfect circle on the roller end surface (the axial end surface of the groove roller and the bottom surface of the cylindrical or cylindrical body). It is slid little by little along the arranged annular slide groove. The balance weight is fixed to the annular slide groove with a screw, for example, at a position where the dynamic balance is achieved during the movement.

According to the third aspect of the present invention, when adjusting the dynamic balance of the groove roller, the balance weight is slid little by little along the linear slide groove extending radially around the center point of the end face of the groove roller. Then, the weight is fixed at a position where the dynamic balance is achieved. As described above, since the balance weight is moved while being fitted and guided in the slide groove, adjustment of the dynamic balance becomes relatively easy.

According to the fourth aspect of the present invention, the dynamic balance of the groove roller is adjusted by simultaneously or individually moving a plurality of balance weights using the balance weight moving means. For this reason, fine balance adjustment can be performed relatively easily.

[0017]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic view of a main part of a wire saw to which a groove roller for a wire saw (hereinafter simply referred to as a groove roller) according to a first embodiment of the present invention is applied. FIG. 2 is an enlarged cross-sectional view of the vicinity of an assembly portion of the groove roller. FIG. 3 is a perspective view of the groove roller. FIG. 4 is an enlarged side view of the groove roller.

In FIG. 1, reference numeral 10 denotes a wire saw to which the groove roller of the first embodiment is applied.
Is a device for cutting a single crystal silicon ingot I pulled up by the CZ method into a number of wafers. The wire saw 10 has a wire row 11 in which a number of wires are bundled in a horizontal row. Wire row 11
Is reciprocated by a drive motor between three groove rollers 12 arranged in an inverted triangle shape when viewed from the front. The middle of the two groove rollers 12 arranged on the upper side is the cutting position of the ingot I. Above both sides of the cutting position, for example, a pair of non-illustrated abrasive liquid supply units for continuously supplying the abrasive liquid onto the wire row 11 are provided.

The wire 11a is led out from the bobbin 20 of the pay-out reel 13, is wound around these groove rollers 12, and is wound on the bobbin 21 of the take-up reel 15. The rotation shafts of the supply reel 13 and the take-up reel 15 are connected to output shafts of drive motors 16 and 17, respectively. When the drive motors 16 and 17 are driven and rotated,
Each of the bobbins 20, 21 pivotally supported by the pair of bearings 18 rotates clockwise or counterclockwise in FIG. 1 about the axis thereof, and the wire 11a reciprocates. In FIG. 1, reference numeral 19 denotes a carbon bed for fixing the ingot I, and 19a denotes a lift for the ingot I. Next, the groove roller 12 according to the first embodiment will be described in detail with reference to FIGS.

As shown in FIG. 2, each groove roller 12 according to the first embodiment is pivotally supported between a pair of bearings 30, 31 arranged at predetermined intervals. Each bearing 30,
31 has a cylindrical casing 32 fixed to an external member via a connecting plate (arm) 32a. An inner sleeve 33 is fitted in the cylindrical casing 32. Rotation shafts 35 and 36 are mounted inside the inner sleeve 33 via six bearings 34 so as to be rotatable in the circumferential direction. A water-cooling jacket is provided between the outer surface of the inner sleeve 33 and the connection plate (or arm) 32a to prevent heating of these. The outer end of the rotating shaft 35 projects outward, and a pulley 37 is fixed to this projected portion. Pulley 37
, A V-belt for transmitting a rotational force from a rotary motor (not shown) is stretched. Furthermore, a short, internally threaded bolt hole 35a is formed at the center of the inner end of the rotating shaft 35. In the center of the rotating shaft 36, a bolt hole 36a extending along the axis is formed. These bolt holes 35a, 36
a, a long bolt 3 passes through the center of the groove roller 12;
8 is inserted. At this time, the external thread 38a at the end of the long bolt 38 is inserted into the internally threaded bolt hole 35a.
, The groove roller 12 is integrated with the rotating shafts 35 and 36 on both sides.

The groove roller 12 has a thick steel base 12A made of steel. A large number of wire grooves 12a, which are parallel grooves having a short pitch, are engraved on the outer peripheral surface of the base metal 12A (see a partially enlarged view of FIG. 2 and FIG. 3). Moreover, a urethane rubber 12c is lined with a thickness of 5 to 20 mm on the outer peripheral surface of the roller in which the wire groove 12a is engraved. The outer peripheral surface of the roller is covered with urethane rubber 12c. In addition, a relatively thin roller reinforcing cylindrical member 39 is provided from the center to the vicinity of both ends of the base metal 12A.
Is fitted inside. The roller reinforcing tubular member 39 is not always necessary. Further, as shown in FIGS. 2 to 4, sleeve end plates 40 are fitted into both ends of the base metal 12A. The end plate portion 40a of the sleeve end plate 40 is formed to be thick, and an insertion hole 40b for the long bolt 38 is formed in the center thereof. Moreover, this end plate portion 4
On the outer surface of the outer edge of Oa, two ridges 40c annularly arranged with two slits therebetween are provided integrally.

Each of the ridges 40c is connected to the rotation shafts 35, 36.
Recesses 3 annularly arranged on the end face on the side of the groove roller 12 of FIG.
5b, 36b. In other words, a pair of protrusions at the end of the rotating shaft are fitted into each slit. As a result, the external thread 38a at the tip end of the long bolt 38 passes through the rotary shaft 36 of the bearing 31 and both sleeve end plates 40 of the groove roller 12 and the bolt hole 35a of the bearing 30.
Are screwed into these three members 12, 3
5 and 36 rotate integrally in the circumferential direction. That is, when the pulley 37 is rotated by a rotation motor (not shown), the rotation shaft 3
5. The groove roller 12 and the rotating shaft 36 rotate integrally.

In FIG. 2, reference numeral 41 denotes an inner lid ring for preventing the bearing 34 from protruding outward from the pulley 37 side. An outer lid ring 42 is engaged with the inner lid ring 41. A stop ring 43 is screwed to the rotation shaft 35 and fixes the inner lid ring 42. 44 and 45 are groove rollers 12
It is a lid ring for preventing the bearing 34 from protruding outside. Reference numeral 46 denotes a thick cap which is fitted on the cylindrical casing 32 on the bearing 31 side and covers the head 38b of the long bolt 38. Reference numeral 47 denotes a seal member provided at the center of the pulley 37. Reference numeral 48 denotes a wide ring for positioning the bearing 34.

Next, referring to FIG. 4, a balance weight 50 provided on the outer surface of the end plate portion 40a of both sleeve end plates 40, which is a feature of the groove roller 12 of the first embodiment, and A description will be given of a balance weight moving means which makes this movable. As shown in FIG. 4, on the outer surface of the end plate portion 40a of each sleeve end plate 40, an annular slide groove 51 as an example of a balance weight moving means arranged in a perfect circle around the center point of the outer surface is provided. Has been established. Each annular slide groove 51 is a dovetail groove having a trapezoidal cross section that gradually widens toward the back. In these annular slide grooves 41, for example, two balance weights 50, each of which is a small weight having a weight of 5 to 10 g and a trapezoidal cross section, are movably fitted and arranged. Each balance weight 50 is fixed in position via a screw 52.

Next, a method of cutting the ingot I by the wire saw 10 provided with the groove rollers 12 will be described.
As shown in FIG. 1, the wire saw 10 rotates the bobbin 20 of the pay-out reel 13 by the drive motor 16 while supplying the abrasive fluid from the abrasive fluid supply unit, and draws out the wire 11 a, while the wire saw 10 is wound by the drive motor 17. The bobbin 21 of the take-up reel 15 is rotated to take up the wire 11a. And
By appropriately changing the rotation direction of each bobbin 20, 21,
The wire 11a is reciprocated. At this time, the pulley 37 for each groove roller 12 is rotated by a rotation motor (not shown), thereby rotating the groove roller 12 between the bearings 30 and 31 (see FIGS. 2 and 3). As a result, the wire row 11 reciprocates between the three groove rollers 12, and the ingot I is pressed against the wire row 11 from above when the wire row 11 reciprocates. Thereby, one ingot I is cut into many wafers. That is, when the wire train 11 reciprocates, the free abrasive grains in the abrasive liquid are removed from the wire train 1.
By rubbing the bottom of the cutting groove with one wire 11a, the bottom is gradually scraped off, and finally a large number of thin wafers are cut.

By the way, in the first embodiment, the three groove rollers 12 of the wire saw 10 are used to improve the flatness of the obtained wafer and to improve the flatness of the ingot I after refining the wire grooves 12a on the outer peripheral surface. 11a at the time of cutting
In order to reduce the occurrence rate of disconnection, the dynamic balance is adjusted. That is, the lining urethane rubber 1
When grinding or re-cutting the groove 2c, the dynamic balance is adjusted thereafter. When the urethane rubber 12c becomes too thin, the urethane rubber 12c itself is peeled off and re-made. In this embodiment, when the dynamic balance of the groove roller 12 is lost due to such re-cutting or the like, as shown in FIG.
The screws 52 for fixing the positions of the individually arranged balance weights 50 are loosened. Then, the balance weight 50 is gradually rotated clockwise or counterclockwise in FIG. 4 along the annular slide groove 51. When the dynamic balance is achieved on the way, each screw 52 is screwed in at that position, and the balance weight 50 is fixed.

As a method of achieving dynamic balance, for example, a reflection seal is attached to the outer periphery of each groove roller 12 and
The rotation number and the origin of the angle are detected by monitoring the rotating reflection seal by a fiber sensor or the like. On the other hand, an acceleration sensor is arranged above each groove roller 12, and the respective vibration displacements are obtained by these acceleration sensors. Ask. In addition, the frequency of each groove roller 12 is detected using a general vibrometer, and the unbalance amount of each groove roller 12 is obtained based on the detected frequency. When the unbalance amount exceeds a predetermined range, balance adjustment is performed.

As described above, the balance weight 50 is moved on the outer surface of the sleeve end plate 40 fitted inside the both ends of each groove roller 12 so as to achieve a balance. Therefore, conventionally, the lining of the urethane rubber 12c is conventionally used. Accompanying roller groove 1
The dynamic balance, which had been a problem when remodeling 2a,
Can be taken with relatively simple operation. Thereby, every time the lining of the urethane rubber 12c is performed, axial vibration occurs in the rotating shaft of the groove roller 12, and between these groove rollers 12,
The phenomenon that the wire 11a is locally pulled or loosened is eliminated. As a result, it is possible to improve the flatness of the wafer and to reduce the incidence of wire breakage during ingot cutting. In addition, since the balance weight 50 is moved while being fitted and guided in the annular slide groove 51, adjustment of the dynamic balance is further simplified. Also, since two balance weights 50 are attached to one annular slide groove 51, fine adjustment of the dynamic balance becomes relatively easy by appropriately adjusting the amount of movement of these balance weights 50.

Next, a groove roller for a wire saw according to a second embodiment of the present invention will be described with reference to FIG. FIG. 5 is an enlarged side view of a groove roller for a wire saw according to a second embodiment of the present invention. As shown in FIG. 5, the groove roller 60 of the second embodiment has an annular slide groove of the first embodiment on the outer surface of the end plate portion 61a of both sleeve end plates 61 fitted inside both ends of the base metal 12A. In this example, a linear slide groove 62 which is another example of the balance weight moving means is provided in place of 51. The linear slide grooves 62 are two grooves (grooves extending in the radial direction) radially opposed to each other with the center point of the outer surface of the end plate portion 61a as a center. Similarly to the above, it is a groove having a trapezoidal cross section gradually expanding toward the back side. In FIG. 5, reference numeral 61b denotes a bolt hole, and reference numeral 61c denotes a number of ridges arranged annularly at a constant pitch on the outer surface of the outer edge of the end plate 61a. These ridges 61c are fitted into the recesses 35b, 36b of the corresponding rotating shafts 35, 36, as in the first embodiment.

In the use of the groove roller 60 of the second embodiment, when adjusting the dynamic balance of the groove roller 60, the balance weight 50 is moved to the linear slide groove extending radially on the outer surface of the end plate portion 61a. The slider is slid little by little in a direction away from each other or in a direction close to each other along 62, and a balance weight 50 is fixed by a position fixing screw 52 at a position where dynamic balance is achieved in the middle. Other configurations, operations, and effects are the same as those in the first embodiment, and thus description thereof is omitted. In addition, as a method of attaching the balance weight, for example, a method of attaching a weight with a double-sided tape, a method of attaching with a magnetic force, and the like can be considered in addition to the above embodiment.
Both have the advantage that the adjustment can be made very easily. Further, in the above embodiment, since the bearing portion is cooled by the water jacket, the groove roller elongates due to a temperature rise (20 to 30 μm).
The generation of warp (warpage) of the wafer due to the above can be effectively prevented.

[0031]

According to the present invention, the balance weight is moved on the end face of the groove roller by the balance weight moving means at the time of dynamic balance adjustment of the groove roller, for example, after the roller groove of the groove roller is modified. The dynamic balance of the groove roller can be adjusted in a short time by a simple operation. Thereby, the flatness of the wafer can be improved. In addition, the rate of occurrence of wire breakage during ingot cutting can be reduced.

In particular, according to the second and third aspects of the present invention, since the balance weight is slid along the annular slide groove or the linear slide groove, the balance of the groove roller can be easily adjusted.

According to the fourth aspect of the present invention, the plurality of balance weights are moved by the balance weight moving means to adjust the dynamic balance of the groove rollers, so that fine balance adjustment can be easily performed. Can be.

[Brief description of the drawings]

FIG. 1 is a schematic diagram of a main part of a wire saw to which a groove roller for a wire saw according to a first embodiment of the present invention is applied.

FIG. 2 is an enlarged sectional view of the vicinity of an assembly portion of the groove roller according to the first embodiment of the present invention.

FIG. 3 is an enlarged perspective view of a groove roller according to the first embodiment of the present invention.

FIG. 4 is an enlarged side view of the groove roller according to the first embodiment of the present invention.

FIG. 5 is an enlarged side view of a groove roller for a wire saw according to a second embodiment of the present invention.

[Explanation of symbols]

10, 60 wire saw, 11a wire, 12, 61 groove roller (groove roller for wire saw), 51 annular slide groove (balance weight moving means), 50 balance weight, 62 linear slide groove (balance weight moving means), I ingot.

 ──────────────────────────────────────────────────の Continuing from the front page (72) Inventor Takumi Kiyama 1-5-1, Otemachi, Chiyoda-ku, Tokyo Mitsubishi Materials Silicon Corporation

Claims (4)

[Claims] 1. A wire saw for cutting one ingot into a number of wafers, wherein a wire is wound in a coil shape. A balance weight moving means is provided on an end face of the wire saw groove roller. A wire roller for wire saws that is provided with a balance weight that can be moved through it. 2. The balance weight moving means has an annular slide groove which is arranged in a perfect circle around a center point of an end face of the groove roller, and the balance weight moves along the annular slide groove. The groove roller for a wire saw according to claim 1 movably provided. 3. The balance weight moving means has a linear slide groove extending radially around a center point of the roller end face, and the balance weight moves along the linear slide groove. The grooved roller for a wire saw according to claim 1, which is provided so as to be capable of being provided. 4. The groove roller for a wire saw according to claim 1, wherein a plurality of the balance weights are used.