WO2012164757A1

WO2012164757A1 - Device for machining columnar member

Info

Publication number: WO2012164757A1
Application number: PCT/JP2011/066526
Authority: WO
Inventors: 将太澤井; 将雄樋口
Original assignee: 新東工業株式会社
Priority date: 2011-05-31
Filing date: 2011-07-21
Publication date: 2012-12-06
Also published as: TWI589398B; JP2014147978A; CN103282173A; TW201247365A

Abstract

Provided is a device for preventing cracks and defects when a substrate composed of a hard brittle crystal material is manufactured. A holding means holds both ends of a workpiece, and the distal end of a polishing brush, which is a machining means, is brought into contact with the workpiece and rotated to thereby remove very small cracks present in the surface layer of the workpiece. Grindstone and polishing-brush machining are used in combination in accordance with the shape and dimensions of the workpiece prior to machining, whereby the shape and dimensions can be adjusted and very small cracks can be removed.

Description

Columnar member processing equipment

The present invention relates to an apparatus for processing an outer peripheral surface of a columnar body that is a block made of a hard brittle crystal material. “Hard and brittle” refers to the property of being extremely hard but vulnerable to impact and easily cracked.

Wafers made of hard and brittle crystal materials used as various semiconductor substrates are generally obtained by thinly cutting a block of the crystal material with a wire saw, a band saw or the like, and then chamfering or finishing polishing. At this time, if a microcrack is present on the surface layer of the block, the microcrack serves as a base point in the above-described cutting or chamfering process, and a crack or chip occurs, resulting in a decrease in yield. Also, in the post-process after the wafer formation, the microcrack becomes a base point and cracks and chips occur. Therefore, it is preferable that no microcracks exist on the surface layer of the block. For example, Japanese Patent No. 3973843 has been proposed as a method for preventing cracks and chips during cutting by polishing the outer periphery of a block of crystalline material.

Japanese Patent No. 3973843 exemplifies a quadrangular columnar silicon block. The block of crystal material has various shapes such as polygonal column shape, cylindrical shape, and other irregular shapes, and since the sizes are various, an inexpensive and high-performance processing device that can be applied to processing of all crystal materials is required. Yes. An object of the present invention is to provide a processing apparatus for obtaining a block of a crystal material with high dimensional accuracy while removing microcracks on the outer peripheral portion of the crystal material.

In order to solve the above-mentioned problems, the processing apparatus of the present invention is a processing apparatus for processing the outer peripheral surface of a crystalline material having a columnar hard brittle shape, and both ends of the processing apparatus are processed when the workpiece is processed. A clamping means comprising a clamping shaft that clamps the surface and attaches a clamping part for releasing the clamping state after the end of processing to move forward and backward, and is connected to the clamping means, and is centered on the axis of the clamping means A workpiece rotating means for rotating the workpiece, a machining unit in which a machining means for machining the workpiece while a tip rotates in contact with the workpiece, and the workpiece before machining. Height position detecting means for detecting the height position of the processed surface of the workpiece, the height position of the workpiece before the processing and the height position after the processing (that is, the height position to be processed) And machining conditions are input and calculated to calculate A control unit that outputs a signal for controlling a machining process of the apparatus, and a determination unit that determines whether the workpiece is in a shape that can be machined, wherein the calculation is performed before and after machining. Either the calculation of the difference from the height position of the object, the calculation for setting other processing conditions based on the input processing conditions, or the combination thereof was used. (First invention)

Moreover, the height position which is the dimension of the workpiece after the processing described in the first invention is controlled by detecting the height position of the outer peripheral surface of the master workpiece having the dimension of the workpiece after the processing. You may input into a means. (Second invention)

Further, the determination described in the first or second invention may be performed by calculating a difference in height position of the workpiece before processing and after processing (processing target). (Third invention)

Further, the processing means according to the first invention is a polishing brush, and the polishing brush has a structure in which a plurality of bristle materials containing abrasive grains are planted in a ring shape at the bottom of the polishing brush. May be. (Fourth invention)

Further, the processing means according to the first invention is a polishing brush, and the polishing brush has a plurality of base parts of a polishing tool in which a plurality of bristle materials containing abrasive grains are bundled on a rotating disk. It may have a structure. (Fifth invention)

The processing means according to the first invention is a polishing brush, and the polishing brush has a structure in which an elastic body containing abrasive grains is arranged in a ring shape at the bottom of the polishing brush. Good. (Sixth invention)

Further, the processing means according to the first invention is a grindstone, and the grindstone has a lump in which abrasive grains are bonded to each other by a binder, and is fixed to one plane side of a disk-shaped rotating disk. The body surface may rotate in contact with the processed surface of the workpiece. (Seventh invention)

Further, in the processing unit described in the first invention, a plurality of processing means described in the fourth to sixth inventions may be connected horizontally. (Eighth invention)

Further, the processing unit according to the first invention may horizontally connect at least one or more of the polishing brush according to the fourth to sixth inventions and the grinding stone according to the seventh invention. (9th invention)

The processing apparatus according to the first invention includes a first processing means and a second processing means arranged on the same cross section of the workpiece, and includes the first processing means and the second processing means. The shaft core is disposed so as to coincide with the radial direction of the workpiece, and the shaft core of the first processing means and the shaft core of the second processing means are configured to form a predetermined angle θ. You may arrange | position so that it may cross in the cross-sectional center of a workpiece. (Tenth invention)

A processing apparatus according to an eighth aspect of the present invention includes a first processing unit and a second processing unit arranged on the same cross section of a workpiece, and includes a first processing unit and a second processing unit. The shaft core is disposed so as to coincide with the radial direction of the workpiece, and the shaft core of the first processing means and the shaft core of the second processing means are configured to form a predetermined angle θ. You may arrange | position so that it may cross in the cross-sectional center of a workpiece. (Eleventh invention)

A processing apparatus according to a ninth invention includes a first processing unit and a second processing unit arranged on the same cross section of the workpiece, and includes a first processing unit and a second processing unit. The shaft core is disposed so as to coincide with the radial direction of the workpiece, and the shaft core of the first processing means and the shaft core of the second processing means are configured to form a predetermined angle θ. You may arrange | position so that it may cross in the cross-sectional center of a workpiece. (Twelfth invention)

Further, in the processing apparatus according to the eighth invention, two or more types of processing means having different particle sizes of the abrasive grains mixed in the bristle material are F180 to # 2000, and the processing means is selected. In addition, the particles may be arranged so as to be polished in the order of “rough” to “fine”. (13th invention)

Further, the processing unit in the processing apparatus according to the ninth aspect of the present invention comprises a grinding wheel having a grain size of F90 to F220 or # 240 to # 500 (according to JIS R6001: 1998) constituting the grinding wheel, and for rough polishing. A polishing brush and a polishing brush for finish polishing, and the grain size of abrasive grains contained in the bristle material or elastic body of the rough polishing polishing brush is # 240 to # 500, and is included in the finish polishing brush The grain size of the abrasive grains may be # 800 to # 1200. (14th invention)

By the processing apparatus according to the first invention, fine cracks existing at 200 μm or less from the surface layer of the columnar member are removed, and the surface roughness Ry (according to JIS B0601: 2001) of the polished surface is processed to 3 μm or less. May be. (15th invention)

The columnar member described in the first invention is hard and brittle such as silicon, ceramics, crystal, sapphire, gallium arsenide, gallium phosphide, gallium nitride, silicon carbide single crystal, lithium tantalate, lithium niobate, indium phosphide, etc. It may be a crystalline material. (Sixteenth invention)

The columnar member described in the first invention is a crystal, and the processing apparatus removes microcracks on the outer peripheral surface of the crystal lambad or laminates a thin plate sliced from the crystal lumbard to form a lump. You may use for the removal of the micro crack of the outer peripheral surface of this lump. (Seventeenth invention)

The processing means provided in the processing apparatus comes into contact with the outer peripheral surface of the workpiece and rotates, whereby the surface layer portion of the workpiece is polished and the microcracks are removed. At that time, depending on the shape of the workpiece, it cannot be processed into a predetermined dimension, and therefore it can be determined by the determining means whether or not polishing is possible (first, second and third inventions).

When the dimension of the workpiece is close to the target dimension and only the surface layer needs to be polished, the processing means can be a polishing brush as described in any of the fourth to sixth inventions. When the polishing brushes are connected horizontally as in the eighth invention, the polishing time can be shortened when the polishing brushes having the same processing ability are arranged. When polishing brushes having different processing capacities are arranged as in the thirteenth invention, rough polishing to final polishing can be performed in one operation.

When the dimension and shape of the workpiece are different from the target dimensions, the processing means may be a grindstone as described in the seventh invention, or may be combined with a polishing brush as in the ninth invention. Good. At that time, the grain size of the abrasive grains constituting the grindstone and the grain size of the abrasive grains contained in the polishing brush are selected from the scope of the fourteenth aspect of the invention, and appropriately arranged to adjust the dimensions by grinding with the grindstone and rough polishing by the polishing brush. And finish polishing can be performed in one operation.

Processing time can be shortened by arranging processing means or processing units as in the tenth to twelfth inventions.

The processing apparatus according to the present invention can be suitably used for processing of all hard and brittle materials. For example, in the process of forming a wafer of a crystal material such as silicon, ceramics, glass, crystal, sapphire, gallium arsenide, gallium phosphide, gallium nitride, silicon carbide single crystal, lithium tantalate, lithium niobate, indium phosphide, etc. It can be used suitably. By removing microcracks existing below 200 μm from the surface layer of these materials and processing the surface roughness Ry of the polished surface to 3 μm or less, the process during slicing and after slicing (for example, forming a substrate) Generation of defective products due to cracking or chipping in the process of mounting or mounting the substrate in the apparatus, etc. can be prevented. Also, in the manufacturing process of crystal wafers, processing of the outer peripheral surface of the crystal lumbard or processing of the outer peripheral surface of a lump that is made by laminating the crystal lumbard thinly, it is possible to prevent problems caused by cracks and chipping in the subsequent process. Generation of non-defective products can be prevented. (15th, 16th and 17th inventions).

This application is based on Japanese Patent Application No. 2011-121646 filed on May 31, 2011 in Japan, the contents of which form part of the present application.
The present invention will also be more fully understood from the following detailed description. However, the detailed description and specific examples are preferred embodiments of the present invention and are described for illustrative purposes only. This is because various changes and modifications will be apparent to those skilled in the art from this detailed description.
The applicant does not intend to contribute any of the described embodiments to the public, and the disclosed modifications and alternatives that may not be included in the scope of the claims are equivalent. It is part of the invention under discussion.
In this specification or in the claims, the use of nouns and similar directives should be interpreted to include both the singular and the plural unless specifically stated otherwise or clearly denied by context. The use of any examples or exemplary terms provided herein (eg, “etc.”) is merely intended to facilitate the description of the invention and is not specifically recited in the claims. As long as it does not limit the scope of the present invention.

It is explanatory drawing explaining the processing apparatus in this embodiment. It is explanatory drawing which shows an example of the polishing brush in 1st Embodiment. It is explanatory drawing which shows the example of a change of the process means in 1st Embodiment. It is explanatory drawing explaining arrangement | positioning of the process means in 4th Embodiment. It is explanatory drawing explaining the mount frame in this embodiment. It is explanatory drawing explaining the example processed into a square pillar-shaped workpiece from a column shape. It is explanatory drawing for demonstrating an example of the manufacturing process of a crystal wafer. FIG. 10 is an explanatory diagram for explaining Example 4;

As a first embodiment of the processing apparatus of the present invention, a workpiece is processed into a cylindrical shape by a processing apparatus including a processing unit in which three polishing brushes having different polishing roughnesses are connected in parallel (three) as processing means. Taking as an example, the details of the configuration and operation of the machining apparatus will be described with reference to the drawings. In the following description, the up / down / left / right directions refer to the directions in the drawings unless otherwise specified.

FIG. 1 shows the cylinder drive of the clamping means 13 on the left and right in the drawing of the machining unit 20 stopped at the right end of the drawing before the machining start and the workpiece W placed by the two-dot chain line on the gantry 11. Shows the open state in which the clamping portion 13a at the tip of the reference-side clamping shaft 13A that slides and the clamping portion 13b at the tip of the driven-side clamping shaft 13B are retracted and the workpiece W is not clamped. FIG. 2 is a front view of a processing apparatus, and the processing unit 20 includes a polishing brush that is selected and set with three different types of abrasive grains for “rough polishing”, “medium polishing”, and “finish polishing”. Each processing means 21 is connected from the right side to the left side in the drawing, and the height position of the processing surface P of the workpiece W is detected before starting the processing on the right side in the drawing of the “rough polishing” processing means 21. For this purpose, a height position detecting means 15 is arranged.

“Rough polishing” in the above-described three processing means 21 is provided for the purpose of scraping most of micro cracks existing in the surface layer portion with a large polishing ability, and “medium polishing” was cut with a band saw or a wire saw. It is provided for the purpose of removing irregularities on the surface that is sometimes generated and refining the roughened surface by the “rough polishing”, and “for final polishing” is provided for the purpose of final adjustment of the surface roughness. It should be noted that the processing means 21 may be doubled if the removal of surface irregularities and the adjustment of the surface roughness are completed at the stage of “medium polishing”.

Prior to processing the workpiece W, the master work is used to set the height position at which the polishing processing of the processing means 21 is started by the height position detection means 15.
In order to set the height position, first, both ends of the master work are clamped by the clamping means 13. When the master work is sandwiched by the sandwiching means 13, it is preferable that the master work is placed on a gantry 11 having a V-shaped groove (notch V: 11b) in the receiving member as shown in FIG. By disposing the master work in the groove, the center of the master work in the direction perpendicular to the paper surface in FIG. 5B is adjusted. Furthermore, it is more preferable that the gantry is connected to lifting means 12 for adjusting the vertical installation position in FIG. A master work is placed on the gantry and the clamping shaft 13A of the clamping means 13 is advanced to the reference end face position B located on the right side in the figure, and then the clamping shaft 13B is advanced to be mastered by the clamping

portions

13a and 13b. Hold both ends of the workpiece. Thereafter, the mount is removed. In this embodiment, the workpiece W is placed on and removed from the gantry 11 by moving the gantry 11 in the vertical direction in FIG.

The clamping means 13 includes a mechanism that rotates about the axis of the

clamping shafts

13A and 13B, and the axis of the clamping

portions

13a and 13b at the tips of the

clamping shafts

13A and 13B as viewed from the end face side of the master work. The centering must be adjusted so that it matches the axis of the master work. In the present embodiment, after the master work is clamped by the clamping means 13, the machining unit 20 is moved to the left, and the height position detection means 15 arranged in the machining unit 20 is used to increase the outer peripheral surface height position H1 of the master work. Then, the master work is rotated (for example, 180 degrees), and the height position H2 in the rotated state is measured. When the difference between H1 and H2 is calculated and H1 and H2 are not substantially the same, the holding

shafts

13A and 13B are moved backward after the gantry is lifted to release the master work. Based on the calculation result, the height position of the gantry (vertical stop position for clamping the master work by the clamping means 13) is adjusted by the lifting / lowering means 12, and then the master work is clamped by the clamping means 13 again. The master work H1 and H2 are measured. When H1 and H2 are substantially the same, the master work centering step is completed.

H1 and H2 after completion of the centering step indicate the height position H of the outer peripheral surface of the master work. After the master work centering step is completed, the machining unit 20 moves to the right end in FIG. Then, the gantry is raised, the

clamping shafts

13A and 13B are moved backward to release the master workpiece, and the master workpiece is placed on the V-shaped groove of the gantry 11. Thereafter, the master workpiece is replaced with the workpiece W, and both ends of the workpiece W are clamped in the same process as that of the master workpiece.

Next, it is determined whether or not the workpiece W has a shape that can be machined. For example, if there is a part where the workpiece W is small relative to the dimension of the processing target or if there is a place that is too large to be suitable for processing with a grindstone or a polishing brush, the processing is stopped as a rejected product. The determination of the shape can be appropriately selected from known techniques such as a three-dimensional measuring instrument, but in this embodiment, the height position of the workpiece W is measured by the height position detector 15 and the determination is made by calculation. went. For example, the workpiece W is rotated by 45 ° in the vicinity of the right end, the center in the left-right direction, and the vicinity of the left end, and a total of 24 height positions are measured, and the difference between these and the height position of the master work is calculated. This makes it possible to make a determination.

The workpiece W that has passed the above determination is subjected to a centering process in the same manner as in the master work. When the centering step is completed, the processing unit 20 is moved to the left end in FIG. In addition, the outer peripheral surface height position H of the master workpiece measured by the centering step of the master workpiece, and the outer peripheral surface height position h of the workpiece W measured by the centering step of the workpiece W, Are stored in the control means 16, respectively.

Processing conditions manually input and stored in advance by the operator in the control means 16 (processing ability of the processing means 21, cutting conditions of the workpiece W in the previous step, rotation speed of the processing means 21, rotation of the workpiece W Speed, the moving speed of the machining unit 20, etc.) and the master work automatically stored in the control means 16 and the height positions H, h of the workpiece before machining are processed, and the machining means A cut amount for the work surface of the workpiece 21 is determined, and a signal of the cut amount is output from the control means 16. Based on this signal, the machining unit 20 is moved in the vertical direction, that is, in the distance direction between the machining unit 20 and the machining surface P. The “cutting amount” is a feed amount of the processing means 21 in the direction of the work piece. The machining allowance of the work piece, the type of the work means, the processing ability of the work means, the physical properties of the work piece, etc. Determined by.

Next, the processing means 21 and the workpiece W are rotated at a predetermined rotational speed by a signal output from the control means 16 based on the processing conditions, and the processing unit 20 is rotated at a predetermined movement speed in FIG. Move to the right. This movement is the movement of the

clamping shafts

13A and 13B in the axial direction, and is also referred to as “back and forth movement”. By this movement, the processing surface P of the workpiece W and the tip of the rotating processing means 21 come into contact with each other, and processing (polishing) is performed. As described above, the processing means 21 has the grain sizes of the abrasive grains contained in the processing means in order from “Rough” → “Fine” in order from the right to the left in FIG. → "Medium polishing" → "Finishing polishing" is performed. When the processing unit 20 moves to a predetermined position (rightmost end), the rotation of the processing means 21 and the workpiece W is stopped. Thereafter, after the gantry 11 is raised and the workpiece W is placed, the

clamping shafts

13A and 13B are retracted, the clamping of the workpiece W is released, and the workpiece W is taken out to perform machining. Complete.

In the case of processing a plurality of workpieces W, after the workpieces W are newly installed on the gantry, the workpieces are similarly processed through a workpiece clamping process and a workpiece centering process. That is, by measuring the height position of the master work first, a plurality of workpieces W can be processed thereafter.

In the present embodiment, the processing unit 20 is moved in the left-right direction in the figure, but the workpiece W may be moved, or both the processing unit 20 and the workpiece W may be moved.

In the present embodiment, the machining conditions are manually input to the control means 16, but the machining conditions that are not input are controlled by the manually input machining conditions and the outer peripheral surface height position that is automatically input (stored). The processing may be performed by calculating at 16. For example, the moving speed of the workpiece W may be calculated by the control means 16 by inputting the cutting amount of the tip of the machining means 21 with respect to the machining surface P of the workpiece and the rotation speed of the machining means 21. The cutting amount may be calculated by the control means 16 from other processing conditions and height positions. And it can process based on these calculation results.

The processing conditions to be input are not limited to the items in this embodiment. For example, the type of the processing means 21, the material of the workpiece W, the shape of the workpiece W before processing, the shape of the workpiece W to be processed, the processing location, and the like may be input.

2 (A) and 2 (B) show an example of a polishing brush as the processing means 21, and a bristle material 24a made of synthetic resin such as nylon mixed with abrasive grains is bundled to form a polishing tool 24. The base 24b of the polishing tool 24 is connected to the processing rotating means 22 and is detachably attached to the polishing tool mounting plate 23 which is rotated horizontally, and the lower end thereof rotates in contact with the processing surface P of the workpiece W for polishing. When the polishing tool 24 is worn, the polishing tool 24 can be removed from the polishing tool mounting plate 23 and replaced with a new polishing tool 24. The polishing brush that is the processing means 21 is not limited to that shown in FIG. 2, and the polishing tool 24 made of the hair material 24 a mixed with abrasive grains is directly attached and fixed to the polishing tool mounting plate 23, and the polishing brush is polished. When the tool 24 is worn, it may be exchanged together with the polishing tool mounting plate 23, or without using the polishing tool 24, a bristle material 24 c made of synthetic resin such as nylon containing abrasive grains is attached to the bottom of the processing means 21. (See FIG. 3A. The upper diagram shows a front view and the lower diagram shows a bottom view). In addition, for example, when the processing means 21 comes into contact with a corner portion of a columnar body that forms an angle of approximately 90 ° during processing, chipping (chipping) occurs due to contact between the processing means 21 and the workpiece W. In this case, an elastic body 24d made of a synthetic resin containing abrasive grains may be arranged in a ring shape at the bottom of the processing means 21 (see FIG. 3B). Represents a bottom view.) The elastic body 24d in this case is, for example, a resin bulk body having a relatively soft hardness, a resin bulk body such as polyurethane or urethane having a large number of bubbles inside, and a fibrous elastic body entangled with each other. It may be a thing. In a bulk body of a resin having a relatively soft hardness, the resin itself functions as a buffer material. In the bulk body of resin having bubbles, the bubbles inside serve as a buffer material. In an elastic body containing abrasive grains and entangled with each other, the elastic bodies are entangled with each other, so that air is included in these aggregates, and this air layer functions as a cushioning material. In any case, the type of synthetic resin, the content of abrasive grains, and the like are appropriately selected so that the elastic body 24d maintains an appropriate elastic force when it contacts the workpiece. The grain size of the abrasive grains mixed with the bristle material or elastic body is F180 to # 2000 (definition of the grain size of the abrasive grains is in accordance with JIS standard R6001: 1998) so that the desired processing capability can be obtained. It is desirable to choose.

Further, at least two kinds of bristle materials or elastic bodies may be arranged for one polishing brush 21. In that case, a bristle material or an elastic body with small abrasive grains is disposed on the side near the outer periphery of the bottom of the polishing brush 21, and a bristle material or elastic body with large abrasive grains is disposed on the inner side. Rough polishing can be performed with bristle materials or elastic bodies having large abrasive grains arranged on the inner side, and intermediate polishing or final polishing can be performed with bristle materials and elastic bodies having small abrasive grains arranged on the outer peripheral side. That is, since two or more effects can be obtained by one polishing brush 21, the number of polishing brushes 21 arranged in the processing unit 20 can be reduced.

Next, a case where a surface required by one-step processing can be obtained without requiring multi-step processing such as “rough” → “thin” as described above will be described as a second embodiment. Here, only differences from the first embodiment will be described.

For example, when the micro cracks on the surface of the workpiece W before processing are very small and the surface roughness before processing is not greatly different from the required value, the processing means 21 (abrasive brush) uses the above-mentioned “medium polishing”. The processing can be performed only for “use” or “for finish polishing”. In such a case, the processing may be performed by arranging only one processing means 21 including a hair material or an elastic body containing abrasive grains having a particle size suitable for the purpose of polishing.

Further, when a plurality of processing means 21 are connected in parallel as in the first embodiment, the processing time can be shortened by arranging the processing means 21 having the same processing ability.

Next, when the workpiece W before finishing is too larger than the dimension intended for finishing, or when the workpiece W before processing is a polygonal column shape, the case where the processing amount is insufficient by polishing with a polishing brush is third. This will be described as an embodiment. Here, only differences from the first embodiment will be described.

In this case, at least one of the processing means 21 may be changed to a grindstone. When arranging the grindstone, for example, in the order from the right in FIG. 1, the grindstone is arranged in the order of “rough polishing brush” and “finish polishing brush”.

In the grindstone, a lump (not shown) in which abrasive grains are bonded together by a binder is fixed on a workpiece W side plane of a rotating disk (not shown). The rotating disk is connected to a processing rotating means 22 for rotating about its axis, and the surface of the fixed abrasive grains is in contact with the workpiece W and is rotated horizontally by rotating with a grindstone. Processing is performed. Note that the bonding between the abrasive grains is performed by, for example, firing the molded article after mixing the abrasive grains, the phenol resin (binder), and the filler at a predetermined temperature. When the bonding strength is weak, glass fibers or the like may be mixed as a reinforcing material at the time of molding, and the binder may be changed in accordance with the polishing power and strength required for the grindstone.

The processing unit 20 includes a mechanism that allows each processing means 21 to move up and down in FIG. After moving the processing unit 20 to the left in FIG. 1, only the grindstone is moved downward and rotated, and the workpiece W is rotated and the processing unit 20 is moved to the right as described above. Processing (grinding) with a grindstone is completed. Next, after raising the grindstone, the processing unit 20 is moved to the left in the figure, and the polishing brush is moved downward to perform the same processing, whereby the processing (polishing) with the polishing brush is completed. Through the above steps, the size and shape can be adjusted with a grindstone, and minute cracks can be removed with a polishing brush.

In order to satisfactorily process a hard and brittle material and not generate new microcracks, it is desirable that the particle size constituting the grindstone is appropriately selected from the range of F90 to F220 or # 240 to # 500. At that time, the grain size of the abrasive grains contained in the bristle material or elastic body of the rough polishing brush is # 240 to # 500, and the grain size of the abrasive grains contained in the hair material or elastic body of the brush for final polishing is # 800 to # 800. It is desirable to select from the range of # 1200 so that the desired processing capability can be obtained.

Next, a processing apparatus according to the fourth embodiment will be described with reference to FIG. In the processing apparatus according to the present embodiment, the processing means 21 is disposed so as to shorten the processing time. Here, only differences from the first embodiment will be described.

In the processing apparatus according to the fourth embodiment, the first processing means 25 and the second processing means 26 are arranged on the same cross section (circular shape) of the workpiece W, that is, on the extension of the cross section.
The axial centers of the first machining means 25 and the second machining means 26 are arranged so as to coincide with the radial direction of the workpiece W, and the first machining means 25 and the second machining means 26 are mutually connected. In order to prevent interference, the axis of the first processing means 25 and the axis of the second processing means 26 form a predetermined angle θ and intersect at the center of the cross section of the workpiece W. (See FIG. 4B. The right figure in the figure shows the front, and the left figure shows the left side.) The angle θ can be arbitrarily set as long as the first processing unit 25 and the second processing unit 26 do not interfere with each other. However, the angle θ is set to 180 ° and the axis of the first processing unit 25 is set. The core and the shaft core of the second processing means 26 can also be disposed so as to completely coincide with each other (see FIG. 4A). The right figure in the figure shows the front and the left figure shows the left side. ).

With such a configuration, the workpiece W is processed while rotating in the circumferential direction, so that the processed surface of the workpiece is at two places, the first processing means 25 and the second processing means 26. Since it is processed simultaneously, processing time is shortened.

Also in the processing apparatus of the present embodiment, the first processing unit 20a in which the first processing means 25 and the second processing means 26 are arranged in two or three in the longitudinal direction of the workpiece W, respectively. And the 2nd processing unit 20b can also be arranged.
In this case, in order from the right along the longitudinal direction of the workpiece W, the first processing means 25a and the second processing means 26a in the first row, the first processing means 25b and the second processing in the second row. The first processing means 25c and the second processing means 26c in the third row are arranged.
At that time, the grain sizes of the abrasive grains contained in the hair material or the elastic body provided in each processing means are the first processing means 25a, the second processing means 26a, the first processing means 25b, and the second processing means. The processing means 26b, the first processing means 25c, and the processing means 26c are substantially the same, that is, have substantially the same processing capability.

Similarly to the second embodiment, when processing can be performed by processing means having one type of processing capability, abrasive grains contained in the hair material or elastic body provided in all processing means. Can be made substantially the same, and the processing ability of all the processing means can be made substantially the same.

In addition, as in the third embodiment, at least one or more processing means in the first processing unit 20a and the second processing unit 20b can be changed to a grindstone.

In the processing apparatus according to the above-described fourth embodiment, the configuration in which the two processing means of the first processing means 25 and the second processing means 26 are installed in the circumferential direction of the workpiece W has been described. However, the present invention is not limited to this, and as long as the respective processing means do not interfere with each other, an arbitrary number of processing means such as third processing means (not shown) according to the installation space, the target processing time, etc. May be further arranged.

Next, a case where the workpiece W is processed into a polygonal column shape (a quadrangular column shape in this embodiment) will be described as a fifth embodiment. Here, only differences from the first embodiment will be described.

First, after placing the master work on a gantry 11 as shown in FIG. 5A, for example, so that the flat surface portion becomes the upper surface, the both ends are clamped by the clamping means 13 (see FIG. 5C, notch L). : 11c). Thereafter, after the height position is measured by the height position measuring means, the clamping is released and replaced with the workpiece W, and the workpiece W is clamped. Thereafter, the gantry 11 is lowered.

Next, it is determined whether or not the workpiece W has a shape that can be processed. For example, if there is a part where the workpiece W is small with respect to the finishing dimension inputted in advance or if there is a part that is too large and is not suitable for processing with a grindstone or a polishing brush, the processing is stopped as a rejected product. Judgment of the shape can be appropriately selected from known techniques such as a three-dimensional measuring instrument, but in this embodiment, for example, 45 ° at each position near the right end, the center in the left-right direction, and the left end of the workpiece W It can be determined by rotating and measuring a total of 24 height positions and calculating the difference between these height positions and the master work height position. In the present embodiment, the height position of the workpiece W is measured by the height position detecting means 15 as in the case of the first embodiment, and the determination is made by calculation. In the case of a quadrangular prism, the calculation is performed considering that the height position is different between the flat portion and the corner portion.

The workpiece W that has passed the above determination is adjusted by rotating with the workpiece rotating means so that the plane that becomes the flat portion after processing is turned upward, and then placed on the gantry 11. Here, when the workpiece W is larger than the target dimension and it is difficult to obtain the target dimension only by processing with a polishing brush, one of the processing means is a grindstone as in the third embodiment. First, the dimensions are adjusted by grinding with a grindstone.

After moving the machining unit 20 to the left in FIG. 1, the measured height position and the cutting amount of the machining means input in advance are calculated, and the machining unit 20 is moved downward in the figure based on the result. Then, the grindstone is lowered and the grindstone is rotated, and then the processing unit 20 is moved to the right in the figure, whereby the shape and size of the first flat portion are adjusted by grinding with the grindstone. Next, after stopping and raising the rotation of the grindstone, the processing unit 20 is similarly moved to the left. After the movement, the polishing brush is lowered and the polishing brush is rotated, and then the processing unit 20 is similarly moved to the right in the figure to complete the processing of the first plane portion.

Thereafter, after the lifting / lowering means 12 is lowered to release the workpiece W, the workpiece W is rotated by 90 ° by the workpiece rotating means, and then the lifting / lowering means 12 is raised to again work the workpiece. Place W on the gantry. Thereafter, the processing of the second plane portion is completed through the same process. By repeating the above steps, the processing of the four sides of the plane portion is completed.

Next, after the lifting / lowering means 12 is lowered to release the workpiece W, the workpiece W is rotated by 45 ° by the workpiece rotating means, and then the lifting / lowering means 12 is lifted to process again. The object W is placed on the gantry 11 (see FIG. 5D. It is placed by the notch V: 11b). Thereafter, the processing of the first ridge corner portion is completed through the same process as the processing of the first flat surface portion. Thereafter, after the lifting / lowering means 12 is lowered to release the workpiece W, the workpiece W is rotated by 90 ° by the workpiece rotating means, and then the lifting / lowering means 12 is raised to again work the workpiece. Place W on the gantry. Thereafter, the processing of the second ridge corner is completed through the same process. By repeating the above steps, the processing of the four ridge corners is completed.

Thereafter, the clamping shafts 13 </ b> A and 13 </ b> B are retracted to release the workpiece W, and are removed from the gantry 11, thereby obtaining the workpiece W in which the processing of the four sides and the four ridges has been completed. Can do.

When the dimension of the workpiece W before processing is not significantly different from the target dimension, the process of adjusting the shape and dimensions can be omitted by using all the processing means 21 as a polishing brush. Similarly, when the step of adjusting the shape and dimensions is performed by another apparatus, the processing means 21 can be processed entirely as a polishing brush.

In the case of a quadrangular prism shape, for example, when a cylindrical workpiece W is processed into a quadrangular prism shape with a wire saw, a band saw, or the like (see FIG. 6), the corner portion is processed when the corner portion is curved. In the state where the mounting on the gantry 11 is released, the workpiece W is processed while reciprocating the rotation of 45 °.

Also, when the target surface is obtained by one-step processing, the processing time can be shortened by arranging a polishing brush having the same processing capability as in the second embodiment.

Moreover, you may arrange | position the some processing unit 20 similarly to the case of 4th Embodiment. For example, when the first processing unit 20a and the second processing unit 20b are arranged with respect to the workpiece and the square columnar workpiece W is processed, the first plane portion and the third Since the plane portion, the second plane portion and the fourth plane portion, the first ridge corner portion and the third ridge corner portion, and the second ridge corner portion and the fourth ridge corner portion are simultaneously processed, the processing time is reduced. Can be halved.
[Example 1]

Processing of cylindrical and quadrangular pillar-shaped silicon blocks that were almost the same as the processing target dimensions. The surface layer portion of the workpiece W before processing has a microcrack having a depth of 80 to 100 μm and a surface roughness Ry of 9 to 11 μm. The silicon block is cut (sliced) with a wire saw. The incidence of defective products due to cracks, chips, etc. when silicon wafers were formed was 5-6%.

In the processing apparatus used in this example, the silicon block as the workpiece (W) is processed by using the processing apparatus described in the first embodiment to remove micro cracks and irregularities, and the surface roughness is reduced to a minute. The results of reducing the incidence of defective products due to cracks, chipping, etc. when the silicon block is formed by slicing the silicon block with a wire saw after the process is completed will be described.

The processing conditions in this example are shown in Table 1, and after inputting to the control means 16, three silicon blocks were processed. As a result, as shown in Table 2, the cylindrical and quadrangular columnar silicon blocks can greatly reduce the depth of microcracks existing on the surface layer of the silicon block and the irregularities on the outer peripheral surface. The maximum depth of microcracks is 0.9 μm, and the surface roughness is a flat portion Ry 0.7 to 1.0 μm (average: Ry 0.9 μm), which eliminates microcracks and irregularities and miniaturizes the surface roughness. It was possible to reduce the incidence of defective products due to cracks, chipping, etc. when all three silicon blocks were sliced with a wire saw into a silicon wafer. The maximum depth of the microcracks is 3.0 μm or less, preferably 2.3 μm or less. When the maximum depth is 3.0 μm or more, the incidence of defective products increases. Further, when the maximum depth is 2.3 μm or less, there is little influence on the occurrence rate of defective products due to cracks / chips or the like when sliced into a thickness of several tens of μm to form a silicon wafer. In this example, the maximum depth was 0.9 μm, which was significantly less than 2.3 μm, which affects the incidence of defective products.

[Table 1]

[Table 2]

[Example 2]

When processing is larger than the target processing size and it is difficult to process with only a polishing brush, cylindrical and square silicon blocks are processed under the conditions shown in Table 3 by combining one grinding stone and two polishing brushes as processing means. In the same manner as in Example 1, three silicon blocks were processed. After calculating the difference between the height position of the silicon block before machining and the machining target dimension, and setting the grinding stone feed amount so that it is larger than the machining target dimension by the machining allowance of the grinding brush, Processing was performed with the feed amount as the conditions in Table 3. As a result, both the cylindrical and square columnar silicon blocks can greatly reduce the irregularities on the outer peripheral surface of the silicon block, and the surface roughness is Ry 0.7 to 1.0 μm (average: Ry 0.9 μm). there were. When each of the three silicon blocks was sliced with a wire saw to form a silicon wafer, the rate of occurrence of defective products due to cracks, chips, etc. was as high as 1 to 2%.

[Table 3]

[Example 3]

As an example of other crystal materials, cylindrical and square columnar crystal blocks that are almost the same as the processing target dimensions were processed. Three crystal blocks were processed in the same manner as in Example 1 under the conditions shown in Table 4. As a result, the irregularities on the outer peripheral surface of the columnar and square columnar crystal blocks could be greatly reduced, and the surface roughness was Ry 0.3 to 0.5 μm (average: Ry: 0.4 μm). When all three of the quartz blocks were sliced with a wire saw to form a quartz wafer, the incidence of defective products due to cracks and chips was reduced by about 2%.

[Table 4]

[Example 4]

As a processing example of a shape other than a quadrangular prism shape or a cylindrical shape, manufacturing of a quartz wafer will be described. As shown in FIG. 7, in order to clarify the axial direction of the artificial crystal, the crystal wafer is obtained by growing a crystal by a hydrothermal growth method or the like to obtain an artificial crystal (see FIG. 7A). Lumbard processing (see Fig. 7B) to obtain a quartz block (hereinafter referred to as "quartz Lambert") by grinding the surface, and cutting by thinly slicing the lumbard artificial quartz crystal at a predetermined angle according to the frequency characteristics Step (see FIG. 7C), the sliced artificial quartz crystals are bonded together with wax or the like to form a lump (for example, 50 to 70 sheets), a fixing step (see FIG. 7D), the outer shape of the lump A crystal wafer can be obtained through an external polishing step for polishing the wafer to adjust the external dimensions of the wafer, and a peeling step for removing the wax and the like (see FIG. 7E) (see FIG. 7F). ).

For example, as shown in FIG. 8, there are cases where both end faces of the crystal Lambert are not horizontal. In this way, when processing a workpiece having a shape in which both end faces are not horizontal, the clamping

auxiliary members

13c and 13d matching the shape of the tip of the workpiece are coupled to the tips of the clamping

portions

13a and 13b, The workpiece W is clamped by the clamping means 13 via the clamping

auxiliary members

13c and 13d. Thereafter, by processing the outer peripheral surface of the quartz lumbar as described above, it was possible to suppress the incidence of defective products such as cracks and chips in the subsequent cutting process.

In the outer shape polishing step, the depth of microcracks generated in the cutting step or the like and the unevenness on the outer peripheral surface can be significantly reduced by performing the processing with the processing apparatus of the present invention. After processing, the quartz wafer obtained through the peeling step has the fine cracks on the outer peripheral surface removed, so that it is possible to suppress the occurrence of coarse cracks that grew from the micro cracks in the subsequent steps. The rate of defective products could be reduced. For example, when manufacturing a crystal unit using a crystal wafer, the post-process is a process of adjusting the thickness to the frequency by polishing, a process of bonding it with wax, etc., and cutting this into predetermined design dimensions. Forming an electrode by a beveling process for grinding an edge to concentrate vibrations in the center of the crystal piece, a process for removing the wax, an etching process for removing processing alterations and improving the frequency accuracy, and an evaporation method. And a step of enclosing in a casing after final adjustment of the frequency.

Industrial applicability

The block of hard and brittle crystal material processed according to the present invention is thinly cut with a wire saw or a band saw, and then the wafer can be obtained by lapping polishing the cut surface. For example, silicon wafers used for various semiconductor substrates such as thin film solar cell panels, quartz wafers used for electronic devices and optical substrates, sapphire wafers used for LED substrates, gallium arsenide wafers, gallium phosphide wafers, gallium nitride wafers, power The present invention can be applied to the production of all types of wafers such as silicon carbide single crystal wafers used for devices, lithium tantalate wafers and lithium niobate wafers used for SAW filters, and indium phosphide wafers used for ultrahigh-speed semiconductor elements.

Below, the main things among the codes | symbols used by this specification are described collectively.
01 Processing device 11 Base 11a Receiving member 11b Notch V
11c Notch L
12 Lifting means 13 Holding means 13A,

13B Holding shafts

13a, 13b Holding portion 15 Height position detecting means 16 Control means 20 Processing unit 21 Processing means 22 Processing rotating means 23 Polishing tool mounting plate 24 Polishing tools 24a, 24c Hair material 24b Base 24d Elastic body

Claims

A processing apparatus for processing an outer peripheral surface of a crystal material having a columnar hard and brittle shape, wherein both end surfaces are clamped when the workpiece is processed, and the clamped state is released after the processing is completed. A clamping means provided with a clamping shaft attached to the tip of the clamping unit so as to move back and forth;
A workpiece rotating means connected to the clamping means for rotating the workpiece about the axis of the clamping means;
A processing unit in which processing means for processing the workpiece while a tip rotates in contact with the workpiece is disposed;
Height position detecting means for detecting the height position of the processed surface of the workpiece before processing;
The height position of the workpiece before machining, the height position of the workpiece after machining, and machining conditions are input, and these are calculated to output a signal for controlling the machining process of the machining apparatus. Control means, and determination means for determining whether the workpiece is a shape that can be processed,
The calculation is at least one of calculation of a difference between the height position of the workpiece before and after machining, or calculation for setting a machining condition that is not input based on the input machining condition. An apparatus for processing a columnar member, comprising:
The height position, which is the dimension of the workpiece after machining, is input to the control means by detecting the height position of the outer peripheral surface of the master workpiece having the dimension of the workpiece after machining. The columnar member processing apparatus according to claim 1.
The columnar member processing apparatus according to claim 1, wherein the determination is performed by calculating a difference in height position between the workpiece before and after the processing.
2. The polishing brush according to claim 1, wherein the processing means is a polishing brush, and the polishing brush has a structure in which a plurality of bristle materials containing abrasive grains are planted in a ring shape at the bottom of the polishing brush. The columnar member processing apparatus described.
The processing means is a polishing brush, and the polishing brush has a structure in which a plurality of base parts of a polishing tool in which a plurality of bristle materials containing abrasive grains are bundled are embedded in a rotating disk. Item 2. The columnar member processing apparatus according to Item 1.
2. The columnar shape according to claim 1, wherein the processing means is a polishing brush, and the polishing brush has a structure in which an elastic body containing abrasive grains is arranged in a ring shape at the bottom of the polishing brush. Member processing equipment.
The processing means is a grindstone, and in the grindstone, a lump body in which abrasive grains are bonded together by a binder is fixed to one plane side of a disk-shaped rotating disk, and the surface of the lump body is the surface of the workpiece. The columnar member processing apparatus according to claim 1, wherein the columnar member processing device rotates in contact with the processing surface.
The columnar member processing apparatus according to claim 1, wherein the processing unit includes a plurality of processing means connected in a horizontal manner to the processing means according to any one of claims 4 to 6.
The said processing unit is equipped with at least 1 or more each of the grinding | polishing brush of the invention of Claim 4 thru | or 6, and the grindstone of the invention of Claim 7, and connected horizontally. The columnar member processing apparatus according to 1.
The processing apparatus includes a first processing means and a second processing means arranged on the same cross section of the workpiece, and the axis of the first processing means and the second processing means is the workpiece core. Arranged so as to coincide with the radial direction, the axis of the first processing means and the axis of the second processing means intersect at the center of the cross section of the workpiece so as to form a predetermined angle θ. The columnar member processing apparatus according to claim 1, wherein the columnar member processing apparatus is arranged in a vertical direction.
The processing apparatus includes a first processing unit and a second processing unit arranged on the same cross section of the workpiece, and the axis of the first processing unit and the second processing unit is the workpiece core. Arranged so as to coincide with the radial direction, the axis of the first processing means and the axis of the second processing means intersect at the center of the cross section of the workpiece so as to form a predetermined angle θ. The columnar member processing apparatus according to claim 8, wherein the columnar member processing apparatus is disposed on the column.
The processing apparatus includes a first processing unit and a second processing unit arranged on the same cross section of the workpiece, and the axis of the first processing unit and the second processing unit is the workpiece core. Arranged so as to coincide with the radial direction, the axis of the first processing means and the axis of the second processing means intersect at the center of the cross section of the workpiece so as to form a predetermined angle θ. The columnar member processing apparatus according to claim 9, wherein the columnar member processing apparatus is arranged in a column.
The processing apparatus selects two or more types of processing means having a grain size of F180 to # 2000 mixed with the bristle material and having different particle sizes. The columnar member processing apparatus according to claim 8, wherein the columnar member processing apparatus is provided so as to be polished in the order of “thin”.
The processing unit includes a grindstone having a grain size of F90 to F220 or # 240 to # 500 constituting the grindstone, a roughing polishing brush, and a polishing brush for finish polishing, and the rough polishing The abrasive grain size contained in the bristle material or elastic body of the polishing brush is # 240 to # 500, and the grain size of the abrasive grain contained in the finish polishing brush is # 800 to # 1200. The columnar member processing apparatus according to claim 9.
2. The columnar member processing apparatus according to claim 1, wherein a microcrack existing at 200 μm or less is removed from a surface layer of the columnar member and the surface roughness Ry of the processed surface is processed to 3 μm or less.
The columnar member is made of a hard and brittle crystal material such as silicon, ceramics, crystal, sapphire, gallium arsenide, gallium phosphide, gallium nitride, silicon carbide single crystal, lithium tantalate, lithium niobate, indium phosphide, etc. The columnar member processing apparatus according to claim 1, wherein the columnar member is processed.
The columnar member is a crystal, and the processing apparatus removes microcracks on the outer peripheral surface of the crystal lumbard, or forms a lumpy body by laminating a thin plate sliced from the crystal lambard, and then the outer peripheral surface of the lumpy body. The columnar member processing apparatus according to claim 1, wherein the columnar member processing apparatus is used for removing at least one of microcracks.