JP2804960B2 - Ingot cutting method and ingot cutting device used therefor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technique for cutting a workpiece and, more particularly, to a technique for cutting a thin substrate from a semiconductor ingot, and more particularly to a technique for aligning a lower surface of the semiconductor ingot with a blade surface of a cutting device. Related to useful techniques to apply.

[0002]

2. Description of the Related Art Generally, a cutting apparatus called a slicer is used to cut (slice) a semiconductor ingot manufactured by a pulling method or the like to produce a thin substrate (wafer). As this cutting device,
It has a holding part capable of vertically holding a workpiece, that is, an ingot, and a rotating blade (a blade for slicing) rotating in a horizontal plane, and cuts out a substrate while alternately repeating lowering and slicing of the ingot. Vertical slicers are known.

[0003] In the above slicer, the holding portion can adjust the inclination of the held ingot. Then, conventionally, after attaching an ingot in which a surface having a desired crystal orientation is exposed to the lower end surface in advance, the inclination is adjusted so that the lower surface of the ingot is parallel to the blade surface. Since then, a substrate for actual element formation, that is, a substrate as a product has been cut out.

[0004]

In adjusting the inclination of the ingot in the vertical slicer described above,
As shown in FIG. 5, after attaching the ingot 1 to the holding portion (omitted in FIG. 5), the lower portion of the ingot 1 is once cut, and the crystal orientation of the cut surface 10a of the cut piece 10 is measured. It was confirmed that the surface of the desired orientation (shown in a horizontal stripe pattern in FIG. 5) and the blade 2 were parallel (FIG. 5A).

However, in general, the ingot 1 is often attached to the holding portion in an inclined state. In practice, the ingot 1 is mounted on the basis of the crystal orientation measured at the time of checking the parallelism. The inclination has to be obtained, and the inclination of the holding section has to be corrected based on the inclination. Then, in order to eliminate the oblique cut surface 1a of the ingot 1 generated by the previous cutting and expose a surface of a desired orientation to the lower surface 1b (FIG. 5C), the lower portion of the ingot 1 must be cut again. (FIG. 5B).

As described above, conventionally, two slices must be normally performed before starting to cut out a substrate as an actual product, and the cutting time for the two cuts and the first cut piece 10 There is a problem that the measurement time of the crystal orientation is lost, and the efficiency of the cutting operation of the substrate is low. Further, the first and second cut pieces 10 and 11 have to be discarded or used as raw materials for newly manufactured ingots, and cannot be used as substrates for actual products. There is also a problem that the yield of the obtained number of substrates is reduced.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to make the end face of a work piece into a blade surface without cutting the work piece (ingot) as preparation. An object of the present invention is to provide a method for cutting an ingot which can be easily adjusted so as to be parallel to the ingot. Another object of the present invention is to provide an ingot cutting device used for performing the cutting method.

[0008]

In order to achieve the above-mentioned object, the present invention provides a flat plate-shaped lower part of a workpiece which is held vertically by adjusting its inclination by a blade rotating in a horizontal plane. When cutting is performed using a cutting device that can be cut into pieces, a detachable inclination detecting jig including at least three displacement meters is attached to the cutting device body, and the at least three displacement meters are used. Abutting the flat lower surface of a detachable zero-adjusting jig that has been positioned in advance so as to be parallel to the blade surface, resetting the displacement of the displacement meter, and zeroing the displacement meter. After doing
The jig for zero adjustment is removed, the lower surface of the workpiece is brought into contact with the at least three displacement meters, and the lower surface of the workpiece is brought into contact with the blade surface based on the displacement of each of the displacement meters. It is proposed to correct the inclination of the workpiece so as to be parallel, and then cut the workpiece.

In positioning the jig for zero adjustment, an object serving as a reference for positioning is previously held vertically by the cutting device main body, and the inclination detecting jig is mounted on the cutting device main body. A flat lower surface of the object is brought into contact with at least three displacement meters of the jig for detecting the inclination thereof, and the lower surface of the object is parallel to the blade surface. After resetting the displacement amount and zero-setting the displacement meter, the cutting device body is fitted with the zero-adjusting jig capable of arbitrarily adjusting the inclination, and the lower surface of the zero-adjusting jig is at least The three displacement gauges are brought into contact with each other, and the inclination of the zero adjustment jig is adjusted based on the displacement of each of the displacement gauges so that the lower surface of the zero adjustment jig is parallel to the blade surface. Suggest to do.

Further, in the cutting apparatus used in the above-mentioned cutting method, there is provided a holding portion capable of vertically holding the workpiece by adjusting its inclination, and rotating the lower part of the workpiece by rotating in a horizontal plane. A cutting device main body including a blade capable of being cut into a flat plate, a tilt detection jig including at least three displacement gauges and detachably attached to the cutting device main body, and detachably attached to the cutting device main body. A jig for zero adjustment whose inclination can be adjusted arbitrarily, wherein the jig for zero adjustment is based on the amount of displacement of the displacement meter when the lower surface thereof is in contact with the at least three displacement meters. The inclination of the lower surface is adjusted so that the lower surface is parallel to the blade surface, and the blade is positioned.

[0011]

According to the above-mentioned means, the lower surface of the workpiece is brought into contact with at least three displacement gauges which have been zero-adjusted by using a zero-adjusting jig parallel to the blade surface in advance. The actual inclination of the workpiece is calculated based on the displacement of each displacement meter, and the inclination of the workpiece is adjusted so as to correct the inclination. It can be adjusted to be parallel to the blade surface. In addition, by adjusting the zero adjustment jig in advance so as to be parallel to the blade surface, even if the zero point of the displacement meter may shift due to the operation of the cutting device or the like, a new ingot may be used. The zero point of the displacement meter can be easily adjusted using the zero adjustment jig again before starting the cutting.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An ingot cutting method according to the present invention and an ingot cutting device used therefor will be described below with reference to FIGS. In this embodiment,
A case where a semiconductor ingot is used as a workpiece and a thin substrate (wafer) is cut from the ingot will be described as an example.

FIG. 1 shows an example of a cutting apparatus used for carrying out a cutting method according to the present invention. As shown in FIG. 1, the cutting device 3 includes a cutting device main body 30 having the same configuration as a conventional cutting device, an inclination detecting jig 4, and a zero-pointing jig 5 (not shown) (see FIG. 2). Consists of The apparatus main body 30 holds the ingot 1 and can move in the X, Y, and Z directions and can tilt in the θ ₁ direction and in the θ ₂ direction orthogonal thereto, and the rotating blade 2 rotates in a plane. And

As shown in FIG. 1 and FIG. 2, the tilt detecting jig 4 is formed by integrating and disposing at least three displacement meters 40 so as not to be aligned on the same straight line. The displacement meter 40 may have any mechanism as long as it can measure the displacement in the vertical direction and display the displacement amount. For example, a so-called magnescale is used here.
These magnescales are mounted on a plate material 45 passed over the blade 2 so that the magnescale can be installed on the blade 2 of the apparatus main body 30.

In FIG. 2, the plate member 45 is connected to the apparatus main body 30.
Although the number is not particularly limited, for example, three points A, B, C
Supported by. Needless to say, the jig 4 is detachable from the apparatus main body 30. Further, the displacement meter 40 is connected to a control device such as a computer (not shown), and reads the displacement amount of the upper end 42 of the displacement meter 40 detected by the expansion and contraction of the upper half portion 41 of the displacement meter 40. The information is displayed on a display device (not shown) connected to the device.

As shown in FIG. 2, the zeroing jig 5 is formed by arranging at least three height adjusting screws 51 on a flat plate 50 so as not to be aligned on the same straight line. The respective height adjusting screws 51 are screwed through the flat plate 50 and are supported by the receiving portions 46 of the inclination detecting jig 4. The lower surface (reference surface) 50a of the flat plate 50 can be inclined at an arbitrary angle by turning each height adjusting screw 51 to advance and retreat, and the inclination can be held semi-permanently by a lock mechanism or the like (not shown). Is available.

The holding section 31 of the apparatus main body 30 is connected to the above-mentioned control device (not shown), and the control device uses the control section to determine the direction of the holding section 31 in the θ ₁ direction based on the amount of displacement detected by each displacement meter 40. and Motomari rotation angle theta ₂ direction, a driving source such as a motor may be adapted to the inclination of the holding portion 31 is driven to automatically correct.

Next, a procedure for cutting a substrate from the ingot 1 using the cutting device 3 configured as described above will be described. First, as shown in FIG. 2, the inclination detecting jig 4 is mounted on the apparatus main body 30, and the zero adjustment jig 5 is further mounted thereon. At this time, the zeroing jig 5 is previously adjusted so that the reference surface 50a of the flat plate 50 is parallel to the blade 2 (specific contents of the paralleling will be described later). Then, the respective displacement meters 40 are reset and their displacement amounts are set to zero. Before performing the above-described reset, the ingot 1 having a surface with a desired crystal orientation exposed on the lower surface thereof may be mounted on the holding unit 31 in advance, or the ingot 1 may be mounted after the reset. You may.

Subsequently, as shown in FIG. 3, after removing the jig 5 for zero adjustment, the ingot 1 mounted on the holder 31 is lowered, and the ingot 1 is placed on the upper end 42 of each displacement meter 40. The lower surface 1c is brought into contact. The upper half 41 of each displacement meter 40 expands and contracts in accordance with the inclination of the lower surface 1c of the ingot 1, and the inclination angle and the inclination direction of the ingot 1 are obtained from the respective displacement amounts detected thereby.

Based on the obtained angle and direction, the holding portion 31
Seeking the rotation angle theta ₁ direction and theta ₂ direction, by rotating the holding unit 31 on the basis of it, the lower surface 1c of the ingot 1 is parallel to the blade 2. At this time, if the orientation of the surface exposed on the lower surface 1c of the ingot 1 is deviated from the desired orientation due to a manufacturing error or the like, the deviation is determined in advance, and the deviation is determined in consideration. The rotation angle in each direction may be determined. Thereafter, the inclination detecting jig 4 is removed, and the cutting of the ingot 1 is started. The reset of the displacement meter 40 using the above-described zero-pointing jig 5 may be appropriately performed when the zero point of the displacement meter 40 is shifted from the reset state due to vibration or the like during operation of the cutting device 3. However, preferably, each time a new ingot 1 is mounted on the holding portion 31, the displacement meter 40
It is good to reset.

Next, a specific description will be given of a method of parallel alignment of the zero-pointing jig 5 which is performed in advance before the displacement meter 40 is reset. First, the holding unit 31
Then, an ingot 1 having a surface having a desired crystal orientation exposed in advance on its lower surface is mounted. Then, as in the prior art shown in FIG. 5, the lower part of the ingot 1 is cut with a blade 2 (FIG. 5A), the crystal orientation of the cut piece 10 is measured, and the ingot 1 is determined based on the measurement result. Is corrected, and the lower part of the ingot 1 is cut again (FIG. 5).
(B)). As a result, a surface of a desired orientation is exposed on the lower surface 1b, and the ingot 1 whose surface is parallel to the blade 2 is mounted on the holding portion 31 (FIG. 5C). .

Subsequently, as shown in FIG.
5C, the ingot 1 (that is, an object serving as a reference for positioning) in the state shown in FIG. 5C is lowered, and its lower surface 1 b is brought into contact with the displacement meter 40. .
In this state, the displacement meters 40 are reset and their displacement amounts are set to zero. Thereafter, the ingot 1 is raised, and a jig 5 for zero adjustment is mounted on the jig 4 for detecting inclination, as shown in FIG. Then, the height adjusting screws 5 are adjusted so that the displacement readings of the displacement meters 40 are all the same.
Turn 1 appropriately.

When the displacements of the displacement meters 40 coincide with each other, the reference surface 50 a of the zero-pointing jig 5 is parallel to the blade 2. Thereafter, the screws 51 are fixed to prevent the height adjusting screws 51 from further retreating. Thereby, the inclination detecting jig 4 is placed on the apparatus main body 30, and
Further, the reference plane 50a is always parallel to the blade 2 simply by placing the zeroing jig 5 thereon.

Therefore, when the blade 2 or the holding portion 31 is disassembled or replaced, the above-mentioned zero-pointing jig 5 is required.
Is performed, it is not necessary to perform the parallel alignment of the zero adjustment jig 5 again unless such disassembly or replacement is performed thereafter. That is, when cutting the substrate from the ingot 1, the inclination of the ingot 1 is corrected immediately after the displacement gauge 40 is reset using the zeroing jig 5 which is aligned in parallel, and cutting is started. I just need.

According to the above-described embodiment, the inclination of the ingot 1 mounted on the holding portion 31 is corrected by using the inclination detecting jig 4 and the zero-adjusting jig 5 which has been previously aligned in parallel. The lower surface of the ingot 1 can be easily adjusted to be parallel to the blade 2. Therefore, it is not necessary to cut the lower part of the ingot 1 each time a new ingot 1 is mounted and the cutting is started as in the prior art, so that the efficiency of the cutting operation is improved and unnecessary cutting pieces are not issued, The number of substrates that can be cut out from one ingot 1 increases, and the yield improves. Further, even if the zero point of the displacement meter 40 is shifted due to the operation of the cutting device 3 or the like, the zero point of the displacement meter 40 can be easily adjusted again by using the zero adjustment jig 5 which has been previously aligned in parallel. Can be.

Actually, a plurality of substrates were cut out from the ingot having a straight body diameter of 2 to 4 inches by using the above-mentioned cutting device 3 and according to the above procedure, and the crystal orientation of the surface of the obtained substrate was examined. In any of the substrates, the deviation from the desired orientation was within 0.25 degrees (allowable value), confirming the effectiveness of the present invention.

The jig 4 for detecting the inclination includes the ingot 1
It is needless to say that the configuration of the above embodiment is not limited as long as the inclination of the lower surface can be detected. For example, displacement meter 4
0 is not limited to the magnescale, but may be any mechanism, such as one using a laser beam, as long as the displacement can be measured and the inclination can be determined based on it. Needless to say, the design of the zero adjustment jig 5 can be variously changed. Further, in the above-described embodiment, the lower portion of the ingot 1 is cut and the lower surface thereof is aligned parallel to the blade 2 as an object serving as a reference for positioning when the jig 5 for zero alignment is aligned. Although an ingot is used, an appropriate workpiece serving as a dummy may be used instead of the ingot 1. Furthermore, the present invention is not limited to cutting the semiconductor ingot 1, but is applicable to slicing a massive workpiece in a specific direction.

[0028]

According to the present invention, the inclination of the workpiece is adjusted using at least three displacement gauges which have been zero-adjusted by using a zero-adjusting jig parallel to the blade surface in advance. With this configuration, the lower surface of the workpiece can be easily adjusted to be parallel to the blade surface without cutting the end face of the workpiece. Therefore,
It is not necessary to cut the end face of the workpiece for parallel alignment, so that the efficiency of the cutting operation is improved, and unnecessary cutting pieces are not generated, and the yield is improved. In particular, when the workpiece is an ingot made of a semiconductor single crystal that takes an extremely long time to manufacture, and when a thin substrate is cut out from the ingot, the number of substrates obtained from one ingot increases. The economic effect is extremely large. Also, even if the zero point of the displacement meter is shifted due to the operation of the cutting device, etc., the zero point of the displacement meter is again adjusted by using the zero adjustment jig which has been adjusted so as to be parallel to the blade surface. The alignment can be easily performed.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an example of a cutting device used for a method of cutting an ingot according to the present invention.

FIG. 2 is a schematic sectional view of a cutting apparatus for explaining a method of cutting an ingot according to the present invention.

FIG. 3 is a schematic sectional view of a cutting apparatus for explaining a method of cutting an ingot according to the present invention.

FIG. 4 is a schematic sectional view of a cutting apparatus for explaining a method for cutting an ingot according to the present invention.

FIG. 5 is a schematic view for explaining a conventional ingot cutting method.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Ingot (workpiece, target object for positioning) 1b Lower surface (flat lower surface of workpiece) 1c Lower surface (lower surface of workpiece) 2 Blade 3 Cutting device 4 Jig for tilt detection 5 Zero adjustment Jig 30 Device main body 40 Displacement gauge 50a Reference plane (flat lower surface of zero-pointing jig)

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) B28D 7/04 B28D 5/02 B24B 27/06 H01L 21/304

Claims (3)

(57) [Claims] 1. A cutting device for cutting a lower portion of a workpiece, which is held vertically by adjusting its inclination, using a cutting device that can be cut into a flat plate by a blade rotating in a horizontal plane. A detachable inclination detecting jig including at least three displacement meters is attached to the main body, and the at least three displacement meters are positioned in advance so as to be parallel to the blade surface. After contacting the flat lower surface of the detachable zero-adjusting jig, resetting the displacement of the displacement meter and zero-setting the displacement meter,
The jig for zero adjustment is removed, the lower surface of the workpiece is brought into contact with the at least three displacement meters, and the lower surface of the workpiece is brought into contact with the blade surface based on the displacement of each of the displacement meters. A method for cutting an ingot, comprising correcting the inclination of a workpiece so as to be parallel, and then cutting the workpiece. 2. When positioning the jig for zero adjustment, an object serving as a reference for positioning is previously held vertically by the cutting device main body, and the inclination detecting jig is mounted on the cutting device main body. A flat lower surface of the object is brought into contact with at least three displacement meters of the jig for detecting the inclination thereof, and the lower surface of the object is parallel to the blade surface. After resetting the displacement amount and zero-setting the displacement meter, the cutting device body is fitted with the zero-adjusting jig capable of arbitrarily adjusting the inclination, and the lower surface of the zero-adjusting jig is at least The three displacement gauges are brought into contact with each other, and the inclination of the zero adjustment jig is adjusted based on the displacement of each of the displacement gauges so that the lower surface of the zero adjustment jig is parallel to the blade surface. 2. The method according to claim 1, wherein the step is performed. Ingot cutting method. 3. A cutting apparatus used in the method for cutting an ingot according to claim 1 or 2, wherein the holding section is capable of adjusting a tilt of the workpiece and holding the workpiece vertically, and rotating in a horizontal plane. A cutting device main body comprising a blade capable of cutting a lower portion of the workpiece into a flat plate shape;
A jig for tilt detection, which is provided with a plurality of displacement gauges and is detachable from the main body of the cutting device; and a jig for zero adjustment which is detachable from the main body of the cutting device and whose inclination can be adjusted arbitrarily. The inclination of the alignment jig is adjusted based on the displacement of the displacement meter when the lower surface thereof is in contact with the at least three displacement meters so that the lower surface is parallel to the blade surface. An ingot cutting device characterized by being positioned.