JP2007119286A - Method and device for processing plate material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method and a device for processing a plate material where the occurrence of chipping at the edge part of a cut groove is suppressed and where the cut groove can be processed by using a whetstone having a simple structure. <P>SOLUTION: On the surface of the plate material W consisting of a highly brittle material, an outer peripheral part is exposed and a member corresponding with small pieces P cut from the plate material W is covered with a masking material M in a masking step. When the plate material W is moved, an exposed surface being not masked with the masking material M is blasted to be rough with a powder and granular material ejected from a blast nozzle 21 and then a half-cut or a full-cut groove is processed with the whetstone 17. The occurrence of chipping at the edge of the cut groove is suppressed by grooving a blasted surface with the whetstone 17 and then the high quality cut groove can be processed. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a plate material processing technique in which a plate material made of a highly brittle material such as an optical glass and a semiconductor wafer used in a liquid crystal device is used as a workpiece, and a kerf is processed in the plate material.

  A liquid crystal device or a mobile phone display is formed by processing a cut groove in an optical glass plate or a glass plate for a substrate and separating the glass pieces into pieces, and a semiconductor integrated circuit device is a plate-like shape on which a circuit pattern is formed. The semiconductor wafer is formed by processing a kerf and separating each device. The shape of the kerf includes a half cut that forms a kerf with a bottom while leaving a part of the plate material, and a full cut that forms a kerf so as to penetrate the plate material. Cutting of a kerf using a hard brittle material such as an optical glass plate or the like, that is, a highly brittle material, as a workpiece is performed using a grindstone.

  As this grindstone, a thin disk-shaped grindstone is used. When a grooving process is performed on a plate whose surface is finished in advance with a grindstone, chipping is performed on the edge of the kerf due to rotational runout of the grindstone. The chipping that is said to occur may occur. If relatively large chipping occurs at the edge, it cannot be used as a product such as a display, and the manufacturing yield is reduced.

In order to prevent chipping from occurring at the edge of the kerf, Patent Document 1 describes a grinding method in which the grinding wheel is shaped by performing electric discharge machining on the side surface portion of the grinding wheel during grinding. . Patent Document 2 describes a blade structure, that is, a grinding wheel, having a disc-shaped dicing blade for cutting a glass plate material and a chamfering blade having a smaller diameter than the dicing blade on the outside thereof.
Japanese Patent Laid-Open No. 7-40241 JP 2002-193632 A

  However, in order to discharge-process the side surface portion of the grindstone during grinding as described above, the grindstone needs to have conductivity, and the material of the grindstone is limited. Further, when the grinding wheel is formed by a dicing blade and a chamfering blade, there is a problem that the structure of the grinding wheel becomes complicated.

  The present inventors conducted various experiments to separate the optical glass plate, which is a highly brittle material, into small glass pieces for display. It has been found that if the grooving is performed with a grindstone after the surface roughness has been roughened in advance, a desired processing quality can be obtained without causing large-size chipping at the edge of the kerf.

  An object of the present invention is to suppress the occurrence of chipping at the edge portion of the kerf and to process the kerf using a grindstone having a simple structure.

  The plate material processing method of the present invention is a plate material processing method for forming a plurality of small pieces on the plate material by processing a half cut or full cut kerf into a plate material made of a highly brittle material such as optical glass, A masking process in which a portion corresponding to the small piece of the surface of the plate material is exposed with a masking material by exposing an outer peripheral portion thereof, and a granular material is sprayed on an exposed surface of the surface of the plate material that is not covered with the masking material. The roughening surface is formed by leaving a roughening surface in a portion corresponding to the outer peripheral portion of the small piece by a blasting process for forming a roughening surface and a grindstone having a width smaller than the width of the roughening surface. And a grinding step for machining the groove.

  The plate material processing method of the present invention is characterized in that the surface roughness of the roughened surface is roughened to a range of 0.02 to 2.50 μm in terms of Ra value by the blasting step.

  The plate material processing method according to the present invention is characterized in that the edge of the kerf is chamfered by spraying a granular material on the roughened surface corresponding to the outer peripheral portion of the small piece.

  The plate material processing apparatus of the present invention is a plate material processing device that forms a plurality of small pieces on the plate material by processing a half cut or full cut kerf into a plate material made of a highly brittle material such as optical glass, A part corresponding to the small piece is provided on a work support base for supporting a plate material whose outer peripheral portion is exposed and covered with a masking material, and a processing head relatively movable along the surface of the plate material; A roughening blast nozzle that forms a roughened surface by spraying particles on an exposed surface that is not covered by the masking material, and a width of the roughened surface provided in the processing head And a grindstone that cuts grooves on the roughened surface while leaving a roughened surface at a portion corresponding to the outer peripheral portion of the small piece.

  The plate material processing apparatus according to the present invention is characterized in that a shaping blast nozzle for shaping the outer peripheral surface of the grindstone by spraying powder particles on the outer peripheral surface of the grindstone is provided in the processing head.

  The plate material processing apparatus according to the present invention includes a chamfering blast nozzle for chamfering the edge of the kerf by spraying powder particles on the roughened surface of the portion corresponding to the outer peripheral part of the small piece after the grooving. It is provided in a processing head.

  According to the present invention, after roughening the exposed surface by spraying the granular material on the exposed surface that is not covered with the masking material among the surface of the plate material, the roughened surface is ground with a grindstone and half-cut or Since the full cut kerf is processed, the occurrence of chipping is suppressed at the edge of the ground kerf, and a small piece can be commercialized with the kerf being processed by the grindstone. The grindstone only performs grooving, and the kerf can be machined with a grindstone having a simple structure, so that the grooving efficiency can be increased.

  After the kerf is processed, the surface roughness of the edge part can be further reduced according to the product by further blasting by spraying powder particles on the edge part of the kerf. By spraying powder particles on the outer peripheral surface of the grindstone, the grindstone can be shaped while being processed, and continuous high-precision grooving can be performed.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. 1 is a front view showing a plate material processing apparatus according to an embodiment of the present invention, and FIG. 2 is a perspective view showing a plate material and a grindstone in the plate material processing apparatus shown in FIG.

  The plate material processing apparatus 10 includes a bed 11 and a processing head 13 mounted on a column 12 attached to the bed 11 so as to be movable up and down as indicated by an arrow Z. A work support 14 for supporting a certain plate material W is mounted. The illustrated plate material W is borosilicate glass (Na2O-B2O3-SiO2), and the surface is mirror-finished. In order to cut a large number of small pieces P from the plate material W, the plate material W is processed with a grid-like cut groove. Is done. The surface of the plate material W is previously covered with a masking material M as shown in FIG. 2 with its outer peripheral portion exposed in the masking step, corresponding to the small piece P to be cut out.

  The work support 14 is mounted on the bed 11 so as to be movable in the machining direction indicated by reference numeral X in FIG. 1 and is also mounted so as to be movable in the positioning direction indicated by reference numeral Y in FIG. On the other hand, a grindstone rotating shaft 16 is rotatably mounted on the machining head 13 which is mounted on the column 12 along the guide rail 15 in the Z direction. A disc-shaped grindstone 17 is mounted on the grindstone rotating shaft 16. It is attached detachably. An electric motor for rotationally driving the grindstone rotating shaft 16 is incorporated in the processing head 13, and the grindstone 17 is rotationally driven in the direction indicated by the symbol R in FIG. Therefore, when the workpiece support 14 is moved to the right in FIG. 1 with the machining head 13 moved downward from the position shown in FIG. Processed.

  A blast nozzle 21 is attached to the processing head 13 for spraying powder on the surface of the plate material W to process the exposed surface of the plate material W that is not covered with the masking material M into a roughened surface. The blast nozzle 21 is a blast nozzle for roughening, and has an opening facing the workpiece support 14. The blast nozzle 21 is attached to the left side in FIG. 1 with respect to the grindstone 17, and when the workpiece support 14 is processed and moved to the right from the position shown in FIG. 1, before the kerf is machined by the grindstone 17. The surface of the plate material W is roughened so that the granular material is sprayed onto the exposed surface that is not covered with the masking material M, so that the exposed surface becomes a satin surface.

  A blast nozzle 22 for shaping that shapes the outer peripheral surface of the grindstone 17 by spraying powder particles toward the outer peripheral surface of the grindstone 17 is attached to the processing head 13, and the blast nozzle 22 is attached to the outer peripheral surface of the grindstone 17. It has an opening. Further, a blast nozzle 23 is attached to the machining head 13 so as to be positioned on the opposite side of the blast nozzle 21 through the grindstone 17. The blast nozzle 23 is a blast nozzle for chamfering for chamfering the edge of the kerf by spraying a granular material on the outer periphery of the shard after the kerf is processed by the grindstone 17 and the shard is processed. And has an opening facing the workpiece support 14. Each of the blast nozzles 21 to 23 may be a dry blast nozzle that ejects the granular material together with air, or may be a wet blast nozzle that ejects the granular material together with the liquid.

  The roughening blast nozzle 21 ejects a granular material having an average particle diameter of 20 μm (# 800), and the shaping blast nozzle 22 has an average particle diameter in the same manner as the roughening blast nozzle 21. Ejects 20 μm (# 800) particles. On the other hand, the chamfering blast nozzle 23 ejects a granular material having an average particle diameter of 6 μm (# 2000). However, the particle diameter of each granular material is not limited to that described above, and is set to an arbitrary particle diameter according to the type of the plate material W or the like.

  FIG. 3 is a plan view showing a procedure for processing kerfs in a glass plate W using the plate processing apparatus shown in FIG. As shown in FIG. 3, when a kerf is machined in order to cut a large number of small pieces P from a single plate material W, the workpiece 17 is moved to the right from the left side in FIG. Move relative to W in the left direction. When one kerf is processed in the entire X direction of the plate material W, the work support 14 is moved back and positioned in the Y direction to process another kerf. In this way, in the case of the plate material W shown in FIG. 3, after processing five kerfs in the X direction, the work support 14 is indexed and rotated 90 degrees, and similarly five kerfs in the X direction. When 16 is processed, 16 pieces P are cut out from the plate material W by the cut grooves that are processed in the X direction and the Y direction by 5 pieces into a lattice shape. In the figure, the outline of the portion of the small piece P that is to be cut out by machining the kerf in the plate material W is indicated by a solid line.

  In FIG. 3, the lowermost portion of the plate material W in the drawing has already been grooved by the grindstone 17, and the work support 14 is moved to move to move the kerf to the upper strip-shaped exposed surface. It shows the state. A masking material M is applied in advance to a portion corresponding to each small piece P, leaving a peripheral portion of the small piece P to be commercialized on the surface of the plate material W, and the workpiece support 14 is being processed and fed. When the granular material is sprayed onto the exposed surface from the blast nozzle 21, the exposed surface is roughened as shown by cross-hatching in FIG. In the figure, the portion roughened by the blasting process is indicated by the symbol T.

  FIG. 4A is an enlarged perspective view showing a part of the plate material W in a state where the exposed surface is roughened by the blasting process, and FIG. 4B is a view in which the kerf S is processed by the grinding process. It is a perspective view which expands and shows a part of board | plate material W in the state which exists.

  As the grinding wheel 17 for grinding for processing the kerf S, those having a thickness dimension G of about 100 to 300 μm are used. The width dimension B of the exposed surface that is not covered by the masking material M is set to be larger than the thickness G of the grindstone 17, and small pieces P are formed on both sides of the cut groove S having a width corresponding to the thickness dimension G of the grindstone 17. A rough surface having a width C corresponding to the outer peripheral portion remains. The width C is set to about several μm to several hundred μm. After the cut groove S is processed on the roughened surface of the outer peripheral portion, the granular material from the blast nozzle 23 for chamfering is sprayed to chamfer the edge of the cut groove S.

As the abrasive grains constituting the grindstone 17, diamond, that is, diamond abrasive grains, is used, and the average particle diameter is 0.1 to 300 μm. However, instead of diamond, cubic boron nitride (CBN) abrasive grains or CBN may be used, a mixture of diamond and CBN may be used, and silicon carbide SiC or GC. , Mullite (3Al ₂ O ₃ -2SiO ₂ ), or molten alumina Al ₂ O _3, that is, WA alone or a mixture thereof may be used. Vitrified bonds are used as the binding material constituting the grindstone 17, but various bond materials such as resinoid bonds, metal bonds, and electrodeposition bonds can be used as the respective binding materials in addition to vitrified bonds. .

  In order to cut out the small piece P by processing the kerf S in the plate material W by the processing apparatus shown in FIG. 1, the portion corresponding to the small piece P to be commercialized is previously exposed by the masking material M so as to expose the outer peripheral portion thereof. cover. The surface of the plate material W before being covered with the masking material M is finished to a mirror surface that is in a commercialized state. As shown in FIG. 2, the surface of the plate material W that has undergone the masking process has a surface of the masking material M and an exposed surface that is not covered by the masking material M. In this state, the plate material W is mounted on the work support base 14 of the processing apparatus shown in FIG. 1. When the plate material W is processed and moved by the work support base 14, first, a powder is applied from the blast nozzle 21 to the surface of the plate material W. Granules are sprayed and the exposed surface becomes a roughened surface T. The groove S is processed by the grindstone 17 on the roughened surface T by the subsequent processing feed movement. By grinding the surface that has become the roughened surface T in advance by the grindstone 17, The number of chipping and chipping mainly decreased at the edge portion.

  The reason why the number of chippings at the edges is reduced if the surface is roughened by blasting in advance before grinding, and the reason why it is possible to produce a product without post-processing has been precisely clarified. Absent. However, even if rotational wobbling occurs in the grindstone 17, the surface is roughened by the blasting process, so it is presumed that the occurrence of a phenomenon in which chipping generated during grinding grows greatly is suppressed.

  In the case shown in FIG. 4, the kerf S is formed so as to penetrate the plate material W and is fully cut. If the back surface of the plate material W is mirror-finished, chipping will occur at the edge of the kerf S on the back side, so it is necessary to reduce the number of chippings on the back side and commercialize the product. When there is, it is preferable to perform blasting on the back side in advance. When it is necessary to leave the back side of the small piece P to be commercialized as a mirror-finished surface, the masking material M similarly applies the masking process corresponding to the small piece P on the back side.

  When the bottomed kerf S is processed by the grindstone 17, the plate W is half-cut by the grindstone 17 so that a part of the plate W is left. When a plate material with a bottomed groove is produced as it is, the plate material is produced by processing the groove on the plate material by half-cut. In the process, the bottom portion of the kerf S may be removed.

  FIG. 5 shows a case where the surface of the plate material W made of glass (borosilicate glass) is subjected to a grooving process after the surface is roughened, and a case where the surface is cut without performing the surface roughening process. It is a measurement result which shows the number of chippings per unit length which generate | occur | produces in the edge part of a kerf. FIG. 5 shows the chipping size dc (μm) generated at the edge portion of the comparative example in which the roughening process was not performed and Examples 1 to 5 in which the roughening process was performed, and the chipping for each size. The number of occurrences per mm. In FIG. 5, when counting the number of chippings, one peak having a vertex is defined as one chipping, and the chipping size is defined as a vertical distance from the peak of the peak to the processing end.

  Table 1 shows the surface roughness Ra (JIS B 0601-1982) and the maximum height Rmax (JIS B 0601-1982) of the exposed surface before grooving in the comparative example and Examples 1 to 5. As shown in FIG. 5, in the comparative example, the kerf S is processed by the grindstone 17 while maintaining the mirror surface without roughening the surface of the plate material W. The average roughness of the exposed surface was varied by changing the particle size of the ejected powder.

  According to the measurement of chipping, as shown in FIG. 5, as the surface roughness of the roughened surface is increased, the number of occurrences per unit length of chipping generally decreases, and the chipping size is reduced. . That is, when the surface roughness of the exposed surface of the portion where the kerf is processed is roughened in the range of 0.02 to 2.50 μm in terms of the Ra value, chipping having a size larger than that of the comparative example is caused. Without occurrence, the number of chipping occurrences was greatly reduced. Preferably, if the lower limit of the Ra value is 0.40 μm and the surface is roughened to a range of 0.40 to 2.50 μm with the Ra value, the number of chippings can be further suppressed and high quality processing is possible. It becomes.

  Thus, when grinding is performed after the processing surface is roughened in advance, a small piece of optical glass that can be commercialized as a display for a liquid crystal device or the like in a state where the kerf S is merely processed by the grindstone 17. P could be cut out from the plate material W. If the surface roughness by the blast treatment is too rough, the quality as a product is deteriorated, so the upper limit Ra value is set to 2.50 μm. However, the upper limit Ra value can be increased depending on the type of small pieces to be commercialized.

  After the cut groove S is processed, when a granular material having a particle size smaller than the powder ejected from the roughening blast nozzle 21 is sprayed from the chamfering blast nozzle 23 to the edge portion of the cut groove S, Compared with the case shown in FIG. 5, the surface roughness of the outer peripheral part of the small piece P can be made small, and product quality can be improved more.

  If powder particles are sprayed from the shaping blast nozzle 22 to the outer peripheral surface of the grindstone 17 while the kerf S is being machined by the grindstone 17, the grindstone 17 is always shaped at the time of machining, so the grinding efficiency of the grindstone 17 is reduced. Without making it possible, it is possible to continuously process the kerf S on the surface of the plate material W.

  The present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the scope of the invention. For example, in the embodiment, the case of slicing into small pieces using the glass plate material W has been described, but if a kerf is processed with a grindstone using a hard brittle material, that is, a highly brittle material as a workpiece, The technique of the present invention can also be applied to a case where a groove is formed on a plate-shaped semiconductor wafer on which a circuit pattern is formed and dicing is performed for each device. In the processing apparatus shown in FIG. 1, the work support 14 for supporting the plate material W is moved and moved in the X direction toward the grindstone 17. The grindstone 17 may be processed and moved with respect to the plate material W. Furthermore, each processing may be performed by separate devices without performing the blasting and grinding by the processing device 10.

It is a front view which shows the processing apparatus of the board | plate material which is one embodiment of this invention. It is a perspective view which shows the board | plate material and grindstone in the processing apparatus of the board | plate material shown in FIG. It is a top view which shows the procedure which processes a cut groove in the glass-made board | plate material with the board | plate material processing apparatus shown in FIG. (A) is a perspective view which expands and shows a part of board | plate material in the state by which the exposed surface was roughened by the blast process, (B) is one of the board | plate materials in the state by which the kerf was processed by the grinding process. It is a perspective view which expands and shows a part. Units generated at the edge of the kerf when the grooving is performed after the surface of the glass plate is roughened and when the grooving is performed without performing the roughening process. It is a graph which shows the measurement result of the number of chippings per length.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Processing apparatus 11 Bed 12 Column 13 Processing head 14 Work support stand 16 Grinding wheel rotating shaft 17 Grinding wheel 21 Blast nozzle (blast nozzle for roughening)
22 Blast nozzle (Blasting nozzle for shaping)
23 Blast nozzle (Blast nozzle for chamfering)
M Masking material P Small piece S Cut groove

Claims (6)

It is a processing method of a plate material that forms a plurality of small pieces on the plate material by processing a half cut or a full cut groove on a plate material made of a highly brittle material such as optical glass,
A masking step of covering a portion corresponding to the small piece of the surface of the plate material with a masking material by exposing an outer peripheral portion thereof;
A blasting step of forming a roughened surface by spraying powder on an exposed surface not covered with the masking material among the surface of the plate material;
A grinding step of machining a kerf on the roughened surface by leaving a roughened surface in a portion corresponding to the outer peripheral portion of the small piece by a grindstone having a width smaller than the width of the roughened surface. The processing method of the board material.   2. The plate material processing method according to claim 1, wherein the roughening surface is roughened in a Ra value range of 0.02 to 2.50 μm by the blasting step. 3. Method.   3. The plate material processing method according to claim 1, wherein the edge of the kerf is chamfered by spraying powder particles on the roughened surface corresponding to the outer peripheral portion of the small piece. A processing apparatus for a plate material that forms a plurality of small pieces on the plate material by processing a half cut or a full cut groove on a plate material made of a highly brittle material such as optical glass,
A workpiece support base for supporting a plate material covered with a masking material by exposing an outer peripheral portion of a portion corresponding to the small piece;
A rough surface that is provided in a processing head that is relatively movable along the surface of the plate material, and forms a roughened surface by spraying powder particles onto an exposed surface that is not covered by the masking material among the surface of the plate material. Blast nozzles for
A grindstone that is provided in the machining head and has a width narrower than the width of the roughened surface and leaves a roughened surface in a portion corresponding to the outer peripheral portion of the small piece, and cuts a groove on the roughened surface. The board | plate material processing apparatus characterized by having.   5. The processing apparatus for a plate material according to claim 4, wherein a blast nozzle for shaping that shapes the outer peripheral surface of the grindstone by spraying powder particles on the outer peripheral surface of the grindstone is provided in the processing head. apparatus.   6. The plate material processing apparatus according to claim 4, wherein the chamfer edge is chamfered by spraying a granular material on a roughened surface of a portion corresponding to an outer peripheral portion of the small piece after the grooving. An apparatus for processing a plate material, wherein a blast nozzle is provided in the processing head.

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