JPH0332805A - Correcting method of error of slicing machine - Google Patents

Abstract

PURPOSE:To secure precision and flatness of a wafer after processing by improving straightness of feed table itself or squareness between an inner circumferential blade and a shaft center of a spindle, by a method wherein cutting is performed while controlling a position of a material of a colummar body during the cutting so that errors in straightness and squareness of the feed table are corrected and an end face of the material of the colummar body is ground while moving a magnet in the direction of a rotary shaft. CONSTITUTION:Data of straightness on the basis of a feed quantity of a feed table and squareness with a spindle are measured beforehand and the measured data is applied to a control part 30. Then a control quantity of an ingot 18 through which the straightness and squareness of the feed table becomes appropriate is calculated by the control part 30 on the basis of error quantities of the applied straightness and squareness. Then at the time of cutting, driving signals corresponding to calculated values are applied to piezoelectric elements 28A, 28B, 28C, 28D each through the control part 30, those of which are driven respectively at the same time and an ingot 18 held with a holding tool is controlled so that the same is at the optimum position to an inner circumferential blade 20.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for correcting errors in a slicing machine, and more particularly, a method for correcting errors in a slicing machine that uses a slicing machine to manufacture flaky wafers from columnar material. Regarding.

C. Prior Art] A slicing machine used for manufacturing semiconductor wafers moves a silicon ingot formed into a columnar body in a direction perpendicular to the axis of a rotating inner peripheral blade.
Cut into thin semiconductor wafers. With the recent demand for higher precision wafers, the performance required of slicing machines has also improved, especially the straightness of the feed table that moves the ingot in a direction perpendicular to the axis of the inner blade and the spindle axis of the inner blade. The perpendicularity between the center and the feed table has a large effect on the precision and flatness of the wafer after processing.

Therefore, conventionally, by increasing the mechanical dimensional accuracy of the feed table and its drive device, the straightness of the feed table itself has been increased, or the perpendicularity of the inner peripheral cutter with the spindle axis has been improved to improve the accuracy of the machining process. We ensure the accuracy and flatness of the wafer.

[Problem to be solved by the invention]

However, there is a limit to increasing the mechanical accuracy of the feed table in terms of machining accuracy.

The present invention was made in view of the above circumstances, and it is possible to improve the precision of the wafer to be cut by correcting the errors in the straightness and squareness of the feed table during cutting. The purpose is to provide a correction method.

[Means to solve the problem]

In order to achieve the above object, the present invention includes a columnar material attached to a feed table that is slidably supported by the device main body, and grinds the end face of the columnar material with a grindstone so as to be orthogonal to the sliding direction of the feed table. In a slicing machine that cuts columnar material into thin wafers with a cutting blade installed on a spindle with an axis in the direction of Based on the perpendicularity data with the feed table, the position of the columnar material is controlled during cutting to compensate for errors in the straightness and perpendicularity of the feed table. It is characterized by grinding the end face of the body material.

[Effect]

According to the present invention, the straightness data of the feed table (12) measured in advance and the spindle axis (
Based on the squareness data between 36) and the feed table (12>), the position of the columnar material (18>) is controlled so as to offset the straightness error and squareness error of the feed table (12).

Thereby, when cutting the columnar material (18), the error of the feed table (12) is forcibly corrected, and the accuracy of the processed wafer can be improved.

In addition, the grindstone (32) for grinding the end face of the columnar material (18) is moved in the direction of its rotation axis so as to eliminate the straightness error and squareness error of the feed table (12), and the end face of the ingot end face is ground. .

Therefore, the ground surface after processing is not affected by the mechanical error of the feed table (12), and desired accuracy can be ensured.

Alternatively, while controlling the position of the columnar material (18), cutting and end face grinding of the wafer are performed while moving the grinding wheel (32) in the ring direction, and the perpendicularity and straightness with the feed table (12) are corrected. .

〔Example〕

Hereinafter, preferred embodiments of the error correction method for a slicing machine according to the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a perspective view schematically showing a slicing machine used in the method for correcting errors in a slicing machine according to the present invention. The slicing machine shown in FIG. 1 has a main body 10, a feed table 12, a column 14, an indexing section 16, etc. as the main gutter bottom. The main body 10 has a feed table 12 indicated by arrow A.
Alternatively, it is provided so as to be slidable in the B direction. Further, a support 14 is erected on the table 12, and an index portion 16 is provided on the support 14. The indexing section 16 supports the ingot 18 in a vertically movable manner, and has a built-in piezoelectric element (described later) that controls the position of the ingot 18, and drives the ingot 18 during cutting to move the ingot 18 on the feed table 12. The ingot 18 is cut while correcting the straightness and squareness.

An inner circumferential blade (cutting blade) 20 for cutting the ingot 18 is disposed at the center of the main body IO.

Figure 2 is a schematic cross-sectional view showing the structure of the ingot holding part;
The figure is an explanatory diagram showing the ingot position control system in Figure 1,
FIG. 4 is a diagram showing straightness data of the feed table 12. As shown in FIG. 2, a holder 26 for holding the ingot 18 is provided at the bottom of the splitting part 16, and the holder 26 has four ingots spaced at 90° intervals as shown in FIG. Piezoelectric elements 28A, 28B, 28C, and 28D are built in (only two are shown in FIG. 2).
For example, a piezo element or the like is used for 28D.

The piezoelectric elements 28A to 28D are connected to a control section 30 of the slicing machine, as shown in FIG. 3, and the squareness data and straightness data of the feed table 12 shown in FIG. 4 are inputted in advance to the control section 30. Ru.

An error correction method for a slicing machine according to the present invention configured as described above will be explained with reference to FIGS. 3 and 4.

First, as shown in FIG. 4, data on the straightness of the feed table 12 relative to the feed amount and the perpendicularity with the spindle 36 are measured in advance, and this measured data is manually input to the control section 30. Then, the control unit 30 calculates the control amount of the inboard 18 that makes the straightness and squareness of the feed table 12 appropriate, based on the manually input error amount (deviation amount) of the straightness and squareness. Next, when cutting, a drive signal corresponding to the calculated value is sent from the control unit 30 shown in FIG. 3 to each piezoelectric element 28.
A, 28B, 28C, 28D, each piezoelectric element 28
A, 28B, 28C, and 28D are driven at the same time to control the ingot 18 held by the holder 26 to be in the optimal position with respect to the inner peripheral blade 20. That is, for example, the amount of deviation in straightness of the feed table 12 is offset by controlling the position of the ingot 18 as indicated by the broken line in FIG.

In this way, errors in the straightness and squareness of the feed table 12 during cutting can be corrected by controlling the position of the ingot 18, and the accuracy of the urchin/% after processing can be improved.

Next, another embodiment of the error correction method for a slicing machine according to the present invention will be described. 5th I! 1 is the inner peripheral blade 2
2 is an explanatory diagram showing the relationship between the grinding wheel 0 and the grinding wheel 32. FIG. Fifth
As shown in the figure, in the slicing machine according to the present invention, a grinding wheel 32 for grinding the end face of the ingot (ilf The end face of the ingot is ground by rotating in the direction C. In this embodiment, a grindstone driving device 3 for vertically moving the grindstone 32 is installed at the bottom of the grindstone 32.
4 are installed. The grindstone drive device 34 is a threaded rod 34A.
1 gear 34B screwed onto threaded rod 34A, 1 output gear 34C meshing with gear 34B, drive motor 35, etc.
The gears 34A and 34B are rotationally driven by the drive motor 35 to move the grinding wheel 32 up and down. The drive motor 35 is connected to the control section 30 shown in FIG.
Normal rotation and reverse rotation are performed by the drive signal output from 0.

Similar to the embodiment described above, the grindstone drive device 34 uses the straightness data of the feed table 12 and the perpendicularity data between the spindle axis 36 of the inner peripheral blade 20 and the feed table 12.
The grinding wheel 32 is driven up and down to correct the amount of deviation. That is, the control 1111s30 appropriately outputs a drive signal that offsets errors in straightness and squareness of the feed table 12 according to the feed amount of the feed table 12, and grinds the ingot while driving the grinding wheel 32 up and down. As a result, the amount of grinding on the wafer end face is adjusted sequentially, and the feed table 1
2, the deviations in straightness and squareness are corrected.

Therefore, poor precision of the wafer caused by misalignment of the straightness and perpendicularity of the feed table 12 during cutting is corrected by controlling the grinding wheel, making it possible to process the wafer with high precision.

In this embodiment, a case has been described in which the position control of the ingot 18 and the movement control of the grinding wheel 32 are performed independently.However, by combining the position control of the ingot 18 and the control of the grinding wheel, the wafer can be ground simultaneously with cutting. You may also do this. This allows cutting and grinding with even higher precision.

〔Effect of the invention〕

As explained above, according to the error correction method for a slicing machine according to the present invention, cutting is performed while controlling the position of the ingot, or cutting is performed while moving the grinding wheel in the direction of its rotation axis. Correct the straightness and squareness of the feed table. Therefore, highly accurate wafers can be manufactured without being affected by errors in the feeding table.

[Brief explanation of drawings]

FIG. 1 is a perspective view schematically showing a slicing machine used in the error correction method for a slicing machine according to the present invention, FIG. 2 is a schematic cross-sectional view showing the structure of a holding part, and FIG. FIG. 4 is an explanatory diagram showing the control system of the slicing machine, FIG. 4 is a graph showing the straightness of the feed table, and FIG. 5 is an explanatory diagram showing the relationship between the inner peripheral blade and the grinding wheel. 12...Feeding table, 18...Ingot (
columnar material), 20...inner peripheral blade (cutting blade), 32
... Grinding wheel, 34... Grinding wheel drive device.

Claims (3)

[Claims] (1) The columnar material is attached so as to be indexed and fed orthogonally to a feed table that is slidably supported on the device body, and is attached to a spindle that has an axis that is perpendicular to the sliding direction of the feed table. In a slicing machine that cuts columnar material into flaky wafers with a cutter blade, the data on the straightness of the feed table and the perpendicularity between the spindle wheel center of the cutter blade and the feed table are measured in advance. A method for correcting errors in a slicing machine, which comprises controlling the position of a columnar material in the spindle axis direction to offset errors in straightness and squareness of a feed table during cutting. (2) The columnar material is attached to a feed table that is slidably supported by the device body, and the end face of the columnar material is ground with a grindstone, and the columnar material is attached to a spindle having an axis perpendicular to the sliding direction of the feed table. In a slicing machine that cuts columnar material into flaky wafers with a cutting blade provided, data on the straightness of the feed table and the perpendicularity between the spindle axis of the cutting blade and the feed table are obtained by pre-measurement. A method for correcting errors in a slicing machine, which comprises moving a grindstone in the direction of its rotation axis to offset errors in straightness and squareness of a feed table during grinding. (3) The columnar material is attached to a feed table that is slidably supported by the device body, and the end face of the columnar material is ground with a grindstone, and the columnar material is attached to a spindle whose axis is perpendicular to the sliding direction of the feed table. In a slicing machine that cuts columnar material into flaky wafers with a cutting blade provided, slicing is performed based on pre-measured straightness data of the feed table and perpendicularity data between the spindle axis of the cutting blade and the feed table. , performing cutting while controlling the position of the columnar material during cutting so as to correct errors in straightness and squareness of the feed table, and grinding the end face of the columnar material while moving the grindstone in the direction of the rotation axis. A method for correcting errors in a slicing machine.