CN110545957B

CN110545957B - Method for cutting workpiece and joined member

Info

Publication number: CN110545957B
Application number: CN201880026727.3A
Authority: CN
Inventors: 丰田史朗
Original assignee: Shin Etsu Handotai Co Ltd
Current assignee: Shin Etsu Handotai Co Ltd
Priority date: 2017-05-02
Filing date: 2018-03-20
Publication date: 2021-07-23
Anticipated expiration: 2038-03-20
Also published as: JP6835213B2; TW201843725A; WO2018203448A1; KR20200002845A; TWI717592B; KR102476617B1; JPWO2018203448A1; CN110545957A

Abstract

The present invention is a method for slicing a workpiece, in which a fixed abrasive wire having abrasive grains fixed to the surface thereof is wound around a plurality of grooved rollers to form a wire row, the fixed abrasive wire is reciprocated in the axial direction, and the workpiece held by a workpiece holder via a joining member attached to the workpiece is cut into the wire row, thereby slicing the workpiece at a plurality of positions arranged in the axial direction simultaneously, wherein a substance partially including a grindstone is used as the joining member, and the fixed abrasive wire is worn by the grindstone of the joining member after the slicing of the workpiece is completed and before the workpiece is pulled out from the wire row. Thus, a workpiece cutting method is provided, which can prevent the occurrence of line marks and the occurrence of line breakage caused by the fixed abrasive grain steel wire being scraped against the workpiece when the steel wire is pulled out after the workpiece is cut.

Description

Method for cutting workpiece and joined member

Technical Field

The present invention relates to a method of cutting a workpiece and a joined member.

Background

Conventionally, as an apparatus for slicing a wafer from a workpiece such as a silicon ingot or a compound semiconductor ingot, a wire saw including a fixed-abrasive-grain steel wire having abrasive grains fixed to a surface thereof is known. In the fixed abrasive grain wire saw, for example, as described in patent document 1, a plurality of fixed abrasive grain steel wires for slicing are wound around a plurality of rollers to form a steel wire row, and the fixed abrasive grain steel wires are driven at a high speed in the axial direction, and a workpiece is cut into and fed to the steel wire row while a working fluid is appropriately supplied, whereby the workpiece is simultaneously sliced at each wire position.

Here, fig. 5 shows an example of a wire saw using a general abrasive grain-fixed steel wire. As shown in fig. 5, the fixed abrasive wire saw 101 mainly includes: a fixed abrasive wire 102 for cutting a workpiece W by fixing abrasive grains to the surface of a wire (high-tensile wire), grooved rollers 103 and 103 ' around which the fixed abrasive wire 102 is wound, a wire row 111 formed of the fixed abrasive wire 102 wound around the grooved rollers 103 and 103 ', means 104 and 104 ' for applying tension to the fixed abrasive wire 102, a means 105 for feeding the cut workpiece W downward, and a means 106 for supplying a coolant 109 (also referred to as a coolant) at the time of cutting.

The fixed abrasive wire 102 is fed from a reel 107 at one end and enters a grooved roller 103 via a tension applying mechanism 104. The fixed abrasive wire 102 is wound around the grooved rollers 103, 103 ' 300 to 400 turns, and then wound up to the reel 107 ' via the tension applying mechanism 104 ' at the other end.

The grooved rollers 103 and 103' are rollers in which urethane resin is pressed around a steel cylinder and grooves are cut at a constant pitch on the surface thereof, and the wound fixed abrasive steel wire 102 can be driven in the reciprocating direction at a predetermined cycle by the driving motor 110.

As shown in fig. 6, the workpiece conveying mechanism 105 of fig. 5 includes a workpiece holding device 114 including a workpiece holding portion 112 and a workpiece plate 113, and the workpiece W is bonded to the workpiece plate 113 via a bonding member (beam) 120 attached to the workpiece W.

When the workpiece W is cut, the workpiece W is held by the workpiece conveying member 105 and is relatively pressed down, and is fed to the wire row 111 formed of the fixed abrasive wire 102 wound around the grooved rollers 103 and 103'. At this time, an appropriate tension is applied to the fixed abrasive wire 102 by the wire tension applying mechanism 104, the fixed abrasive wire 102 is moved in the reciprocating direction by the driving motor 110, the coolant 109 is supplied through the nozzle 108, and the workpiece W is cut and fed by the workpiece conveying member 105 to be sliced into a wafer shape. After the cutting of the workpiece W is completed, the cut workpiece is relatively moved in the direction opposite to the cutting direction, and the cut workpiece is extracted from the wire row 111.

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open publication No. 2011-20197

Disclosure of Invention

Technical problem to be solved

In the wire saw shown in fig. 5 and 6, the moving workpiece W is pushed against one fixed abrasive wire 102 wound around the grooved rollers 103 and cut, and therefore, after cutting is completed, the workpiece W is positioned below the steel wire row 111. Therefore, in order to take out the workpiece W, the wire 102 must be relatively pulled downward through the gap between the workpieces W having the wafer shape by moving the workpiece W upward.

At this time, when the fixed abrasive wire is used, as shown in fig. 7, no clearance is generated between the fixed abrasive wire 102 and the workpiece W. Therefore, the fixed abrasive wire 102 is not easily pulled out, the fixed abrasive wire 102 is scraped and lifted from the workpiece W, and when the fixed abrasive wire 102 is pulled out in this state, the cut surface is damaged and so-called line marks (ソーマーク) are easily generated on the cut surface, whereby warpage (Warp) is deteriorated and quality is deteriorated. Moreover, if the floating of the fixed abrasive grain steel wire 102 increases, the wire may be broken. When wire breakage occurs, it is necessary to take time and effort to rewind the fixed abrasive wire 102 around the grooved rollers 103 and 103', and the fixed abrasive wire 102 and the like that have to be rewound in an additional amount is required, resulting in a large loss.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a workpiece slicing method and a joint member capable of preventing the occurrence of line marks and line breakage due to the fixed abrasive grain wire being scraped against a workpiece when the wire is pulled out after slicing the workpiece.

(II) technical scheme

In order to achieve the above object, the present invention provides a method of slicing a workpiece, in which a fixed abrasive wire having abrasive grains fixed to a surface thereof is wound around a plurality of grooved rollers to form a wire array, the fixed abrasive wire is reciprocated in an axial direction, and the workpiece held by a workpiece holder via a joining member attached to the workpiece is cut into the wire array, thereby simultaneously slicing the workpiece at a plurality of positions arranged in the axial direction, wherein a substance partially including a grindstone is used as the joining member, and the fixed abrasive wire is worn by the grindstone of the joining member after the slicing of the workpiece is completed and before the workpiece is pulled out from the wire array.

According to the workpiece cutting method of the present invention, the fixed abrasive wire can be abraded by the grindstone of the joint member positioned between the workpiece and the workpiece holding device before the workpiece is pulled out from the wire row, and therefore, the fixed abrasive wire can be prevented from being scraped when the workpiece is pulled out. Therefore, according to the method for slicing a workpiece of the present invention, it is possible to prevent the occurrence of a wire mark and wire breakage due to the fixed abrasive wire being scraped against the workpiece.

Further, as the grindstone constituting a part of the joint member, WA (White corundum) grindstone is preferably used.

Thus, the fixed abrasive wire can be more effectively worn by using the WA grindstone, and the workpiece can be more reliably prevented from being scraped and pulled out.

Further, as the WA grindstone constituting a part of the joint member, a grindstone having an abrasive grain size number (artificial hand) of #100 to #10,000 is preferably used.

By setting the abrasive grain size numbers of the WA grindstone to #100 to #10,000 in this way, the fixed abrasive wire can be worn particularly effectively, and seizing of the fixed abrasive wire can be prevented more reliably.

Further, in order to achieve the above object, the present invention provides an engaging member which is attached to a surface of a workpiece held by a workpiece holding device of a wire saw on a side held by the workpiece holding device, wherein a part of the engaging member is constituted by a grinding stone.

The joining member of the present invention is positioned between the workpiece holder of the wire saw and the workpiece when the workpiece is cut, and can abrade the fixed abrasive grains of the wire saw by the grinding stone after the cutting of the workpiece is completed and before the workpiece is pulled out. Therefore, the joint member of the present invention can prevent the occurrence of line marks and the occurrence of line breakage due to the fixed abrasive grain steel wire being scraped against the workpiece.

At this time, the grinding stone constituting a part of the joint member is preferably a WA grinding stone.

In this way, the fixed abrasive wire can be more effectively worn, and the workpiece can be more reliably prevented from being scraped and pulled out.

Further, the abrasive grain size number of the WA stone constituting a part of the joint member is preferably #100 to #10,000.

In this way, the fixed abrasive wire can be worn particularly effectively, and the fixed abrasive wire can be prevented from being scraped more reliably.

The joining member is preferably a laminate composed of a layer to be bonded to one side of the workpiece and a layer to be held by the workpiece holding device, the layer to be bonded to one side of the workpiece is preferably composed of resin, carbon, soda-lime glass, or silicon, and the layer to be held by the workpiece holding device is preferably composed of a grindstone.

If the layer to be attached to the workpiece is made of resin, carbon, soda-lime glass, or silicon, the fixed abrasive steel wire can be reliably worn by the grindstone while the surface of the workpiece is less likely to be scratched.

(III) advantageous effects

According to the workpiece cutting method and the joined member of the present invention, since the workpiece can be pulled out with the worn wire, the clearance between the workpiece and the wire can be ensured, and the workpiece can be pulled out without generating a wire mark or a wire breakage due to the seizure of the wire.

Drawings

Fig. 1 is a schematic view showing an example of a wire saw that can be used for the method for slicing a workpiece according to the present invention.

Fig. 2 is a schematic view for explaining an example of a method for holding a workpiece in the method for cutting a workpiece according to the present invention.

Fig. 3 is a schematic view for explaining a method of cutting a workpiece according to the present invention.

Fig. 4 is a schematic view for explaining a method of cutting a workpiece in examples and comparative examples.

Fig. 5 is a schematic view showing an example of a general wire saw.

Fig. 6 is a schematic diagram showing an example of a workpiece holding device of a general wire saw.

Fig. 7 is a diagram showing a state in which an abrasive wire is fixed in a gap between workpieces.

Detailed Description

The following description will be made of embodiments of the present invention, but the present invention is not limited thereto.

As described above, in the case of using the fixed abrasive wire, since there is no clearance between the cut workpiece and the fixed abrasive wire, the fixed abrasive wire is not easily pulled out, and the fixed abrasive wire is scraped and floated by the workpiece, and when the fixed abrasive wire is pulled out in this state, the cut surface of the workpiece is damaged and so-called line marks are easily generated on the cut surface, and warping deteriorates and deteriorates the quality. Further, if the floating of the fixed abrasive wire increases, wire breakage may occur, and if wire breakage occurs, the fixed abrasive wire must be rewound around the grooved rollers with a lot of labor, or an additional amount of the fixed abrasive wire must be rewound, resulting in a large loss.

Therefore, the present inventors have made intensive studies to solve the above problems. The results show that: the present inventors have found that a workpiece can be pulled out without causing the fixed abrasive wire to be scratched by using a material partially including a grindstone as a joining member to be stuck to the workpiece to cause abrasion of the fixed abrasive wire, and have completed the present invention.

First, a wire saw that can be used in the workpiece cutting method according to the present invention will be described with reference to fig. 1 and 2. As shown in fig. 1, a wire saw 1 includes: a fixed abrasive wire 2 for slicing a workpiece W, a plurality of grooved rollers 3, 3 ' around which the fixed abrasive wire 2 is wound, a wire row 11 formed between the grooved rollers 3, 3 ', tension applying mechanisms 4, 4 ' for applying tension to the fixed abrasive wire 2, a workpiece feeding mechanism 5 capable of holding the sliced workpiece W and performing plunge feed to the wire row 11 and also capable of relatively moving the workpiece W in a direction opposite to the direction of plunge feed, and a machining liquid supply mechanism 6 including a nozzle 8 for supplying a cooling liquid 9 at the time of slicing.

The wire saw 1 is further provided with a set of wire reels 7, 7'. The fixed abrasive wire 2 is fed from a wire reel 7 at one end, passes through a tension applying mechanism 4, and enters a grooved roller 3. The fixed abrasive steel wire 2 is wound around the grooved rollers 3 and 3 ' about 300 to 400 times and then wound up to a steel wire reel 7 ' by a tension applying mechanism 4 ' at the other end. As the fixed abrasive steel wire 2, for example, a steel wire obtained by electrodepositing diamond abrasive grains onto the surface of a piano wire with nickel is used.

The grooved rollers 3 and 3' are rollers for pressing the urethane resin into the circumference of the steel drum and grooving the surface thereof at a constant interval, and the wound fixed abrasive wire 2 is reciprocated in the axial direction at a predetermined cycle by the driving motor 10.

In this wire saw 1, the workpiece W can be held as shown in fig. 2. In other words, the workpiece feeding mechanism 5 has the workpiece holding device 14 constituted by the workpiece holding portion 12 and the workpiece plate 13, bonds the joint member 20 to the workpiece W, and holds this joint member 20 by the workpiece plate 13. Then, the workpiece W can be held by the workpiece holding portion 12 via the joining member 20 and the workpiece plate 13.

Here, the joint member 20 is a joint member of the present invention. In other words, as shown in fig. 2, the joint member is a part of which is constituted by the grinding stone 21.

As shown in fig. 2, the joining member 20 of the present invention is preferably a laminate composed of a layer to be bonded to the workpiece W and a layer to be held by the workpiece holding device 14, the layer to be bonded to the workpiece W is preferably a resin 22, and the layer to be held by the workpiece holding device is preferably a grinding stone 21. If the side to be stuck to the work W is made of resin, the side of the work W is less likely to be scratched. The layer to be attached to the workpiece W may be made of carbon, soda-lime glass, or silicon, in addition to the resin 22. With these materials, the work W is also less likely to be scratched.

Next, a method for cutting the workpiece W using the wire saw 1 will be described with reference to fig. 1 to 3. As shown in fig. 1 and 2, in the wire saw 1, a fixed abrasive wire 2 is wound around a plurality of grooved rollers 3 and 3' to form a wire row 11, the fixed abrasive wire 2 is reciprocated in the axial direction, and the workpiece W held by a workpiece holder 14 is cut into the wire row 11 by a workpiece feed mechanism 5 via a joining member 20 attached to the workpiece W, whereby the workpiece W is simultaneously cut at a plurality of positions arranged in the axial direction.

In the present invention, after the cutting of the workpiece W is completed and before the workpiece W is pulled out from the wire row 11, the fixed abrasive wire 2 is worn by the grindstones 21 of the joint member 20. Specifically, the fixed abrasive steel wire 2 can be worn as follows. In cutting by the wire saw 1, actually, as shown in fig. 3, the workpiece W is cut and fed by an amount obtained by adding a margin to the diameter of the workpiece W, and thus a part of the joining member 20 bonded to the workpiece W in the vicinity of the cutting completion portion is also cut. Therefore, the use of the joining member 20 in which at least a part of the portion cut by the allowance is the grindstone 21 makes it possible to wear the fixed abrasive steel wire 2 when the steel wire row 11 cuts into the grindstone 21. This ensures a clearance between the workpiece W and the fixed abrasive wire 2 when the workpiece W is pulled out from the wire row 11, and prevents the fixed abrasive wire 2 from being scraped and the workpiece W from being pulled out. Therefore, according to the method for slicing a workpiece of the present invention, it is possible to prevent the fixed abrasive wire 2 from being scraped against the workpiece W to cause a wire mark and a wire breakage.

Further, the kind of the grinding stone constituting a part of the joining member 20 is preferably a WA grinding stone. By using the WA grindstone in this way, the fixed abrasive wire 2 can be effectively worn, and the fixed abrasive wire 2 can be more reliably prevented from being scraped.

Further, the abrasive grain size number of the WA stone constituting a part of the joint member 20 is preferably #100 to #10,000. By setting the abrasive grain size numbers of the WA grindstone to #100 to #10,000 in this way, the fixed abrasive wire 2 can be worn particularly effectively, and the occurrence of seizing of the fixed abrasive wire 2 can be prevented more reliably.

Examples

The present invention will be described more specifically by way of examples and comparative examples, but the present invention is not limited to these examples.

(examples)

The workpiece was cut by the method for cutting a workpiece of the present invention. As a work to be cut, a columnar silicon single crystal ingot having a diameter of about 300mm was used. Further, as the steel wire to be cut, a fixed abrasive wire of diamond abrasive grains fixed to a core wire as shown in table 1 below was used.

[ TABLE 1 ]

Core wire diameter	0.140mm
		Diamond abrasive grain	10～20μm
Steel wire external diameter (rating)	0.174mm
		Abrasive particle fixing method	Nickel electrodeposition

The configuration of the joining members and the conditions for cutting the workpieces were set as shown in table 2 below.

[ TABLE 2 ]

As shown in table 2, in the examples, a resin bonding member having a height of 10mm and a WA grinding stone having an abrasive grain size number of #4,000 and a height of 20mm were bonded with an epoxy resin adhesive to be used as a bonding member. As shown in fig. 4, the height of the engaging member was set to 30 mm. In addition, the depth of the cut into the WA grindstone WAs set to 5mm in the examples.

As a result, the fixed abrasive steel wire was not broken during pulling out, and no line mark was observed on the major surface of the cut wafer.

Comparative example

As the joining member, the single crystal silicon ingot was cut under the same conditions as in examples (table 1, table 2, and fig. 4) except that a conventional joining member composed only of resin was used.

As a result, the fixed abrasive steel wire was broken during pulling out, and it was confirmed that the cut wafer had a trace on the main surface.

The results of the above examples and comparative examples are summarized in table 3 below.

[ TABLE 3 ]

The present invention is not limited to the above-described embodiments. The above embodiments are merely exemplary, and any configuration that has substantially the same configuration as the technical idea described in the claims of the present invention and produces the same operational effects is included in the technical scope of the present invention.

Claims

1. A method of slicing a workpiece, in which a fixed abrasive wire having abrasive grains fixed to a surface thereof is wound around a plurality of grooved rollers to form a steel wire row, the fixed abrasive wire is reciprocated in an axial direction of the fixed abrasive wire, and the workpiece held by a workpiece holder via a joining member attached to the workpiece is cut into the steel wire row and fed, thereby simultaneously slicing the workpiece at a plurality of positions arranged in the axial direction of the workpiece,

using, as the joining member, a substance of which a part is a grindstone, so that the fixed abrasive steel wire is abraded by the grindstone of the joining member after the end of cutting of the workpiece and before the workpiece is pulled out from the steel wire row.

2. The method of cutting off a workpiece according to claim 1,

as the grinding stone constituting a part of the joining member, a WA grinding stone WAs used.

3. The method of cutting off a workpiece according to claim 2,

as the WA grindstone constituting a part of the joint member, a grindstone having an abrasive grain size number of #100 to #10,000 WAs used.

4. An engaging member that is to be attached to a surface of a side of a workpiece held by a workpiece holding device of a wire saw held by the workpiece holding device,

wherein a part of the joint member is constituted by a grindstone.

5. The splice component of claim 4,

the grinding stone constituting a part of the engaging member is a WA grinding stone.

6. The splice component of claim 5,

the WA grindstone constituting a part of the joint member has an abrasive grain size number of #100 to #10,000.

7. The joint member according to any one of claims 4 to 6,

the joining member is a laminate composed of a layer attached to one side of the workpiece and a layer held by the workpiece holding device, the layer attached to one side of the workpiece is composed of resin, carbon, soda-lime glass, or silicon, and the layer held by the workpiece holding device is composed of a grindstone.