JP2000176821A - Wire saw - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent slurry adhered to a wafer from being dried after completion of a cutting process, and thereafter easily and quickly clean-remove the slurry adhered to the wafer in the later washing process. SOLUTION: While rows 17 of wires tensed in parallel, are allowed to travel by a wire traveling mechanism, a work 25 is cut by feeding slurry 23 containing free abrasive grains to the rows 17 of wires by a slurry feeding mechanism 19, and by feeding-moving the work 25 in the direction in which the work is brought into contact with the rows 17 of wires by a feed mechanism. When the cutting process of the work 25 is completed, the feed and movement of the work 25 by means of the feed mechanism is stopped, and the running action of the rows 17 of wires by means of the wire traveling mechanism, and the feeding operation of the slurry 23 by means of the slurry feeding mechanism 19 are controlled to be proceeded.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wire saw for cutting a workpiece made of a hard and brittle material such as a semiconductor material, a magnetic material, and a ceramic using a wire.

[0002]

2. Description of the Related Art In a wire saw of this type, a plurality of processing rollers are arranged at intervals, and a single wire is wound around the outer circumference of the rollers many times, whereby the distance between the processing rollers is reduced. , A wire row is stretched in parallel. Then, while the wire row runs along with the rotation of the processing roller, a slurry formed by mixing the dispersion liquid and the free abrasive grains is supplied onto the wire row, and the direction in which the workpiece comes into contact with the wire row in this state. And the workpiece is cut into a wafer.

In the conventional wire saw, when the cutting of the work is completed, the work is moved back in the direction away from the wire row by the work feed mechanism, and the wire row is extracted from between the cut wafers. With this, the operation of the entire machine was stopped. Therefore, if the machine is stopped for a long time in this state, the slurry that has entered or adhered between the wafers or around the wafers is dried and hardened. Is very difficult to remove.

[0004] In order to cope with such a problem, for example, a wire saw having the following configuration has been conventionally proposed. In the first conventional configuration, a slurry tray that is always filled with slurry is disposed below the work, and when the cutting of the work is completed, the work is immersed in the slurry in the slurry tray, and the entire machine is cut. The operation is stopped. In the second conventional configuration, when the cutting of the work is completed, the work is moved back in the direction away from the wire array while the cleaning liquid composed of the dispersion liquid is supplied onto the wire array by the slurry supply mechanism. Can be extracted from between the wafers after cutting (Japanese Patent Application Laid-Open No. Hei 6-114828).

[0005]

However, these conventional wire saws have the following problems.
That is, in the first conventional configuration, the machine is stopped for a long time in a state where the slurry is stored in the slurry receiving tray, so that the free abrasive grains and chips in the slurry are separated from the dispersion liquid and the slurry receiving tray is separated. There is a problem that the sediment precipitates on the bottom of the inside and the sediment solidifies if left.

In the second conventional configuration, the cleaning liquid is mixed into the slurry of the slurry supply mechanism, and the mixing ratio of the dispersion liquid and the free abrasive grains in the slurry is changed. There is a problem that the processing accuracy is adversely affected.

The present invention has been made by paying attention to such problems existing in the prior art. The purpose is to prevent the slurry that has penetrated or adhered to the space between the wafers or around the wafers from drying or hardening after the completion of the cutting of the workpiece, and the subsequent cleaning. It is an object of the present invention to provide a wire saw capable of easily and quickly removing slurry attached to a wafer in a process.

[0008]

In order to achieve the above object, according to the first aspect of the present invention, while the stretched wire train is run by the wire running means, the wire is stretched on the wire train by the slurry supply means. In a wire saw configured to supply a slurry and feed and move at least one of a work and a wire row by a feed means to cut the work, when the cut processing of the work is completed, the feed movement of the work by the feed means And a control means for controlling so as to continue the operation of running the wire train by the wire running means and the slurry supply operation by the slurry supply means.

Therefore, even after the cutting of the workpiece is completed, the traveling operation of the wire train by the wire traveling means is continued while the movement of the workpiece by the feeding means is stopped, and the slurry is supplied by the slurry supply means. Supply operation is continued.

According to a second aspect of the present invention, in the wire saw according to the first aspect, the control means changes and controls the traveling speed of the wire array by the wire traveling means when the cutting of the workpiece is completed. is there.

Therefore, when the traveling speed of the wire array is reduced after the cutting of the work is completed, the power consumed by the continuation of the traveling operation of the wire array can be reduced. According to a third aspect of the present invention, in the wire saw according to the first or second aspect, when the cutting of the workpiece is completed, the control means changes and controls a slurry supply amount by the slurry supply means. is there.

Therefore, also in this case, when the supply amount of the slurry is made small after the end of the cutting of the workpiece, the power consumed as the slurry supply operation is continued can be reduced.

According to a fourth aspect of the present invention, in the wire saw according to any one of the first to third aspects, the control means determines a new line feed amount in a traveling operation of the wire row after the cutting of the workpiece. Change control.

Therefore, even if the running operation of the wire train is continued after the cutting of the work is completed, the wire consumption can be prevented when the new line feed amount is set to zero. For this reason,
Slurry supply to the workpiece cutting portion can be continued for a long time by repeatedly using the used portion of the wire.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the wire saw according to the present invention will be described below with reference to the drawings. As shown in FIG. 1, a column 12 stands on a base 11. A cutting mechanism 13 is provided on one side of the column 12 on the base 11.
Is installed. The cutting mechanism 13 includes a plurality of processing rollers 14, 15, 16 extending in parallel at intervals, and an annular groove (not shown) is formed on the outer periphery thereof.

A wire row 17 extending in parallel is formed between the processing rollers 14, 15, 16 by continuously winding a wire made of a single wire a number of times around these annular grooves. It is stretched. Then, the processing rollers 14, 15, 16 are rotated by a wire traveling motor 18 constituting a wire traveling mechanism as a wire traveling means shown in FIG. 2, and the wire is reeled (not shown).
The wire array 17 is run at a predetermined running speed by being unwound from the reel and wound on another reel (not shown). This wire row 17 is continuously traveled in one direction, or after traveling in one direction by a fixed amount, and then traveling in the opposite direction by the fixed amount smaller amount.
The vehicle may travel stepwise in one direction so that the new line feed amount is constant as a whole.

In the vicinity of the cutting mechanism 13, a slurry supply mechanism 19 as a slurry supply means is disposed to face. That is, a pair of supply nozzles 20 are disposed above the wire row 17 between the processing rollers 14, 15, and 16,
A slurry receiving tray 21 is provided below. And
By the rotation of the slurry circulation pump motor 22 shown in FIG. 2, the slurry 23 obtained by mixing the dispersion liquid and the free abrasive grains is
It is circulated in a circulation path between the slurry receiving tray 21 and at least one of the supply nozzles 20, and is supplied from the supply nozzle 20 onto the wire row 17.

A work support mechanism 24 is vertically movably supported by the column 12, and a work 25 made of a hard and brittle material is adhered to a lower part of the work support plate 27 via an intermediate member 26 such as a glass plate. It is set detachably in a fixed state. Then, the work supporting mechanism 24 is moved up and down via a ball screw or the like by a work elevating motor 28 constituting a feed mechanism as a feeding means shown in FIG.

During operation of the wire saw, the wire row 17 is driven by the processing rollers 14, 15,
While traveling between the 16, the work 25 supported by the work support mechanism 24 is fed downward toward the cutting mechanism 13 and moved. At this time, a slurry containing loose abrasive particles is supplied from the supply nozzle 20 of the slurry supply mechanism 19 onto the wire row 17, and the work 25 is pressed against the wire row 17 to make contact with the wire row 17, and the work 25 is cut into a wafer. Processed.

Next, the circuit configuration of the wire saw configured as described above will be described. As shown in FIG. 2, the control device 29 constitutes a control means for controlling the operation of the entire wire saw, and outputs an operation signal to the wire traveling motor 18, the slurry circulation pump motor 22, and the wire lifting / lowering motor 28. The storage unit 30 stores the feed amount of the work 25, the traveling speed of the wire train 17 and the supply amount of the slurry 23 during the cutting of the work 25, and the traveling speed and the slurry 23 of the wire train 17 after the cutting of the work 25 is completed.
And various data such as the amount of supply. Operation input unit 31
Is operated when inputting the above-mentioned various data or when starting / stopping the wire saw.

Then, as shown in FIGS. 1 and 3, when the cutting of the work 25 by the wire array 17 is completed, the control device 29 stops the feed movement of the work 25 by the work lifting motor 28. At the same time, the traveling operation of the wire train 17 by the wire traveling motor 18 and the supply operation of the slurry 23 by the slurry supply mechanism 19 are continued.

In this case, the control device 29 changes the traveling speed of the wire train 17 by the wire traveling motor 18 so as to be lower than that during the cutting, and controls the traveling of the wire train 17 within a certain range. Repeat the reciprocating operation to change the new line feed amount to zero. Further, the control device 29 changes the supply amount of the slurry 23 by the slurry supply mechanism 19 so as to be smaller than that during the cutting.

Next, the operation of the wire saw configured as described above will be described. In this wire saw, while the wire train 17 is running between the processing rollers 14, 15, 16 of the cutting mechanism 13 by the wire running motor 18, the supply nozzle 20 of the slurry supply mechanism 19 is placed on the wire train 17. Supplies the slurry 23.
In this state, the work supporting mechanism 24 is lowered by the wire lifting / lowering motor 28, and the work 25 is fed downward, and is pressed against and contacts the wire row 17. Thus, the work 25 is cut so that a wafer having a predetermined thickness is cut out.

As described above, the cutting of the work 25 is continued for a predetermined time, and as shown in FIG. 3, when the cut by the wire row 17 reaches the intermediate member 26 and the cutting of the work 25 is completed, the wire elevating and lowering is performed. The feed movement of the work 25 by the use motor 28 is stopped. Then, in this state, the traveling operation of the wire train 17 by the wire traveling motor 18 is continued, and the supply operation of the slurry 23 from the supply nozzle 20 of the slurry supply mechanism 19 is continued.

At this time, the traveling speed of the wire train 17 by the wire traveling motor 18 is changed so as to be lower than that during the cutting process, and the reciprocating travel in which the new line feed amount of the wire train 17 becomes zero. Changed to behavior. Further, the supply amount of the slurry 23 by the slurry supply mechanism 19 is
Change so that it is smaller than during cutting. And
In this state, the traveling operation of the wire array 17 and the supplying operation of the slurry 23 are continuously performed, and the workpiece 2 having been cut is completed.
The slurry 23 is constantly fed between the wafers 5a of FIG.

Therefore, the slurry is continuously supplied between the respective wafers 25a of the work 25 via the wire row 17.
Therefore, even if the cutting process of the work 25 is completed at midnight or the like and left in an end state, there is no danger that the slurry that has entered or adhered between the wafers 25a or around the wafers 25a will be dried.

The effects that can be expected from the above embodiment will be described below. In the wire saw of this embodiment, the work 25
When the cutting of the workpiece 25 is completed, the feed movement of the workpiece 25 by the feed mechanism 28 is stopped by the control of the control device 29, and the wire train 1 by the wire traveling mechanism 18 is stopped.
7 and the slurry 2 by the slurry supply mechanism 19
The supply operation of No. 3 is continued.

Therefore, even after the cutting of the work 25 is completed, the supply operation of the slurry 23 by the slurry supply mechanism 19 to the wafer 25a is continued. Therefore, after the cutting of the work 25 is completed, it is possible to prevent the wafer 25a or the slurry 23 that has entered or adhered to the periphery of the wafer 25a from being dried. The slurry 23 can be easily and quickly removed by washing.
Therefore, it is possible to promptly shift to the next step of processing the wafer 25a.

Further, even after the cutting of the work 25 is completed, the supply operation of the slurry supply mechanism 19 is continued, and
Since the slurry 23 is circulated in the circulation path of the slurry supply mechanism 19, free abrasive grains in the slurry 23 do not separate from the dispersion liquid and stay in the circulation path. Therefore, it is possible to prevent the clogging of the circulation path of the slurry supply mechanism 19 from occurring.

Further, even after the completion of the cutting of the work 25, the same slurry 23 as during the cutting is applied to the work 25.
Therefore, unlike the conventional configuration in which the cleaning liquid composed of the dispersion liquid is supplied, the mixing ratio of the dispersion liquid and the free abrasive grains in the slurry 23 does not change. For this reason, it is possible to prevent a possibility of adversely affecting the processing accuracy during the subsequent cutting of the work 25.

The work 2 is controlled by the control device 29.
When the cutting of No. 5 is completed, the traveling speed of the wire array 17 by the wire traveling mechanism 18 is changed so as to be lower than during the cutting. For this reason, it is possible to reduce the power consumed as the traveling operation of the wire array 17 is continued.

The work 2 is controlled by the control device 29.
When the cutting process of No. 5 is completed, the new line feed amount of the wire row 17 by the wire traveling mechanism 18 is changed from the predetermined amount during the cutting process to zero. For this reason, after the cutting of the work 25 is completed, even if the wire row 17 is running, the new line portion is sent unnecessarily and the new line is not consumed, so that the continuous operation is continued for a long time. Becomes possible.

The work 2 is controlled by the control device 29.
When the cutting process of No. 5 is completed, the supply amount of the slurry 23 by the slurry supply mechanism 19 is changed to be smaller than that during the cutting process. For this reason, after the cutting of the work 25 is completed, it is possible to reduce the power consumed by continuing the supply operation of the slurry 23.

This embodiment can be embodied with the following modifications. When the cutting of the work 25 is completed, the traveling operation of the wire train 17 by the wire traveling motor 18 is continued at the same traveling speed as during the cutting.

When the cutting of the work 25 is completed, the supply operation of the slurry 23 by the slurry supply mechanism 19 is continued at the same supply amount as during the cutting.

[0036]

According to the present invention, the above object is achieved by the following method.
In the invention described in the above, when the cutting of the workpiece is completed,
The feed movement of the work by the feed means is stopped, and the running operation of the wire array by the wire running means and the slurry supply operation by the slurry supply means are continued, so that the intrusion into or between the wafers or around the wafers is prevented. Drying of the attached slurry can be prevented, and the slurry attached to the wafer can be easily and quickly removed.

According to the second aspect of the present invention, when the cutting of the workpiece is completed, the traveling speed of the wire array is changed so as to be lower than, for example, during the cutting.
Power consumption can be reduced.

According to the third aspect of the present invention, when the cutting of the workpiece is completed, the amount of the slurry to be supplied is changed so as to be smaller than that during the cutting, thereby reducing the power consumption. be able to.

According to the fourth aspect of the present invention, after the cutting of the workpiece is completed, for example, the new line feed amount is set to zero so that the new line feed is not performed, thereby preventing unnecessary consumption of the new line. And can continue for a long time.

[Brief description of the drawings]

FIG. 1 is a front view of a main part showing one embodiment of a wire saw of the present invention.

FIG. 2 is a block diagram showing a circuit configuration of a wire saw.

FIG. 3 is a partially enlarged cross-sectional view showing a state in which the cutting of the work is completed.

[Explanation of symbols]

13: cutting mechanism, 14, 15, 16: processing roller, 1
7: wire row, 18: wire traveling motor constituting a wire traveling mechanism as wire traveling means, 19: slurry supplying mechanism constituting slurry supplying means, 20: supply nozzle,
22: motor for slurry circulation pump, 23: slurry, 24
... work support mechanism, 25 ... work, 25a ... wafer, 2
Reference numeral 8: a work lifting / lowering motor constituting a feeding mechanism as a feeding means; 29, a control device constituting a control means; 30, a storage unit.

Claims (4)

[Claims] A slurry is supplied onto a wire array by a slurry supply unit while a stretched wire array is run by a wire running unit, and at least one of a workpiece and a wire array is fed and moved by a feeding unit. In a wire saw configured to cut a workpiece, when the cutting of the workpiece is completed, the feeding movement of the workpiece by the feeding unit is stopped, the traveling operation of the wire train by the wire traveling unit, and the slurry of the slurry by the slurry supplying unit are stopped. A wire saw provided with control means for controlling a supply operation to be continued. 2. The wire saw according to claim 1, wherein the control means changes and controls the traveling speed of the wire train by the wire traveling means when the cutting of the workpiece is completed. 3. The wire saw according to claim 1, wherein the control unit changes and controls the amount of slurry supplied by the slurry supply unit when the cutting of the workpiece is completed. 4. The wire saw according to claim 1, wherein the control means changes and controls a new line feed amount in a traveling operation of the wire row after the cutting of the work is completed.