JP2009056517A - Method and tool for truing diamond wheel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To set the height of the cutting edges of the tip ends of abrasive grains so as to produce a ground surface of a mirror finish level, and also to reduce the resistance in truing, and to make the truing of a thin abrasive wheel possible, and to prevent the metallic contamination due to truing. <P>SOLUTION: A material containing silica glass as a main component is used as a truing tool. The heights of the cutting edges of abrasive grains are arranged by efficiently forming smooth flat portions on the tip ends of the abrasive grains on the surface of a bond by grinding the truing tool by a diamond wheel. The tip ends of the diamond grains wear by grinding the silica glass, and the tip ends of the projecting grains than the average height of the cutting edges are furthermore largely worn by deeply grinding the silica glass, and further the tip ends of the low grains have a small depth of cut, and their wear become small. As a result, the diamond wheels can be trued such that the heights of the cutting edges of the abrasive grains are uniformly arranged. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a truing method for a diamond grindstone and a truing tool used therefor.

  In the field of inspection analysis, a quartz glass cell having a groove for flowing a trace amount of liquid sample is increasingly used. The surface roughness of the grooves requires smoothness and flatness at a mirror surface level in order to allow liquid to flow smoothly and to prevent a decrease in detection sensitivity due to light scattering.

  As a processing method for forming fine grooves in quartz glass, which is a brittle material, a method is known in which quartz glass parts are optically polished and then joined to form grooves, which are manufactured by high-precision polishing and manual processing. Therefore, cost reduction is difficult.

  Further, as a microfluidic chip and μTAS groove forming method, after forming a corrosion-resistant film on a quartz glass substrate and removing a necessary pattern by lithography, etching quartz glass with a hydrofluoric acid-based etching solution, or Although a method of forming a groove by shot blasting is known, there are cases where the performance as an analysis cell cannot be satisfied in terms of optical performance or the shape of the groove cross-section formed.

  On the other hand, there is a grinding method using a superabrasive grindstone such as a diamond grindstone or a CBN grindstone as a method for forming grooves directly in quartz glass by machining. In general, when a diamond grindstone is used, the diamond grindstone bond is removed using a diamond tool, a normal grindstone, or a steel material or other metal as a truing tool, and truing is performed. Since this method is a method of removing the bond or crushing the abrasive grains, the protruding amount of the abrasive grains is not uniform, and the heights of the abrasive grain cutting edges are not aligned microscopically. Therefore, it is difficult to reduce the maximum abrasive cutting depth, which hinders mirror grinding.

Then, the technique of mirror-finishing hard brittle materials, such as optical glass and ceramics, and ductile materials, such as an aluminum alloy, by aligning the abrasive cutting edge height has been studied. Cutting edge alignment inevitably involves flattening of the cutting edge tip.
The “truing” in the present invention means this alignment work. This operation is also called smoothing or shaving.
Therefore, while dressing is an operation that adjusts the protruding amount of abrasive grains and creates a blunted abrasive cutting edge, truing removes run-out of the working surface of the mounted grindstone, This refers to the work of finishing to a predetermined shape according to the shape.
As the truing tool, a flat type, a cup truer type, a rotary truer type or the like is used.
Japanese Patent No. 3286941 JP 2001-212766 A

In grinding with a diamond grindstone, when a diamond tool is used as a truing tool used for aligning the cutting edge height, because the hardness is the same, irregularities that become chip pockets occur in the flat part of the diamond grindstone tip, May cause clogging. Further, since the processing resistance during truing is large, it is difficult to apply it to a cutting blade with a thin blade with low rigidity or a grindstone for grooving.
On the other hand, in the case where a steel material or a cemented carbide material is a truing tool, flatness is difficult to be obtained because plastic deformation is likely to occur at the working portion, and metal contamination may remain on the diamond grindstone.

  In the truing of a diamond grindstone used for grinding brittle materials such as quartz glass, the present invention aligns the height of the abrasive grain cutting edge so that a mirror-level grinding surface can be obtained, and reduces the machining resistance during truing. It is a problem to enable truing of a thin grindstone and to eliminate metal contamination due to truing of a diamond grindstone for grinding a semiconductor component.

  By using a truing tool made of quartz glass as a main component and grinding the truing tool with a diamond grindstone, a smooth flat part is formed at the tip of the abrasive grain on the bond surface with high efficiency, and the abrasive cutting edge height Are arranged. The tip of the diamond abrasive is worn away by grinding the quartz glass, but the tip of the abrasive that protrudes from the average cutting edge height is relatively heavily worn by cutting deep into the quartz glass. The lower abrasive tip is shallower and wear is relatively small, resulting in truing so that the abrasive cutting edge height is aligned.

When the bond of the diamond grindstone is organic, in addition to the above-described effects, the abrasive grains are buried in the bond to increase the abrasive cutting edge density.
One of the factors that reduce the surface roughness of the ground surface is to increase the abrasive cutting edge density, but quartz glass used as a truing tool has low thermal conductivity, and the organic material of the bond also has thermal conductivity. Because it is small, the generated heat is difficult to escape. Accordingly, by performing grinding under appropriate conditions, the organic bond is softened, the diamond abrasive grains are buried in the bond, and the abrasive cutting edge density is increased. As a material for the organic bond, a phenolic resin bond or the like is desirable.

  Truing is performed by grinding the truing tool with a diamond grindstone for cutting and grooving using a material composed mainly of quartz glass as a truing tool. By burying the abrasive grains in the bond or wearing the tip of the abrasive grains, the side run-out is removed, and mirror-level grinding can be performed.

Quartz glass has chemical reactivity with diamond (carbon) and is suitable as a main component of a truing tool. When quartz glass is used alone, it contains almost no metal impurities, so that impurity contamination can be prevented in component grinding for semiconductor applications.
As a form of the quartz glass, a bulk body, a foamed body, a sintered body, or the like can be used.
In addition, by adding a small amount of iron or the like as a main component and adding a small amount of iron or the like as a subcomponent, the effect of diffusion wear can be added to the wear and wear effect of quartz glass, thereby adding functions such as truing effect and dressing action. . As a method for producing such a material, in addition to a method for producing by introducing fine particles containing a desired element component, gas, etc. in flame fusion deposition, electric melting method, soot method, etc., which are conventional methods for producing quartz glass, An injection molding method is preferable, and these subcomponents are pulverized into particles, kneaded into quartz glass powder, and injection molded to produce a truing tool mainly composed of quartz glass having a predetermined shape.

  By using the diamond grindstone truing by the truing method of the present invention, it is possible to satisfy the performance as an analytical cell and to manufacture a quartz glass channel cell for analysis free from metal contamination at low cost. Specifically, it is a multi-step machining process centering on the conventional manual machining, but machining is possible and a reduction in cost is achieved. Further, it is possible to improve the optical low scattering characteristics of the ground surface by forming a smooth flat portion at the tip of the grindstone and increasing the density of the abrasive cutting edge by burying the abrasive.

  In the truing of grinding wheels in which diamond abrasive grains are dispersed in the bond, by using quartz glass as a truing tool, the cutting edge tip of the diamond wheel can be flattened and the height can be aligned. It is possible to achieve high density of the abrasive cutting edge density of the grindstone.

  The surface of the material to be ground that has been ground by the diamond grinding wheel that has been subjected to the truing method of the present invention provides a mirror-level processed surface. can get. In addition, when the bond material of the diamond wheel for grinding is an organic material such as resin bond, the processing heat and processing pressure generated by truing causes the diamond grain to be buried in the bond, resulting in a high cutting edge density. Is effective in improving the mirror surface level of the grinding surface roughness.

The truing method for a diamond grindstone of the present invention can be used for groove grinding of a glass cell having a groove for flowing a trace amount liquid in the field of inspection analysis. The material to be ground is not limited to a quartz cell channel cell component for analysis, and can be applied to all quartz glass grinding products. Moreover, it can utilize for the diamond grindstone for grinding processing of brittle material of general glass and ceramic besides quartz glass. Further, by using high-purity quartz glass as a truing tool, it can be used as a truing method for a grinding wheel for grinding a semiconductor manufacturing apparatus component that is required to prevent impurity contamination.
As described above, since quartz glass has high purity, high hardness, and low thermal conductivity, it has been found that it has a high wear effect on diamond and is effective as a truing tool.

Hereinafter, the present invention will be described based on examples.
Example 1
A truing method of the present invention by attaching a resin bond diamond cutting grindstone having a diameter of 100 mm, a thickness of 0.25 mm, and # 2000 to an outer peripheral blade cutting machine, using the polished quartz glass as a truing tool, and grinding the surface of the quartz glass. Carried out. The truing conditions were a grinding wheel peripheral speed of 30 m / min, a feed speed of 25 mm / min, a cutting depth of 0.25 mm, and a working length of 630 mm.
After truing, when the abrasive grains on the outer periphery of this cutting wheel were observed, the cutting edge tip of the diamond abrasive grains was flattened, and it was observed that the cutting edge was densified by burying the diamond abrasive grains in the resin bond. It was done. The observation result by SEM is shown in the photograph of FIG.

Next, grooving was performed on the quartz glass plate 2 as a work material using the true cutting wheel 1. A schematic diagram of the groove processing is shown in FIG. The groove processing conditions were a grinding wheel peripheral speed of 30 m / min, a feed rate of 2 mm / min, and a cutting depth of 0.25 mm.
When the surface roughness of the groove 3 formed by grinding the quartz glass plate 2 was measured using a laser probe type non-contact three-dimensional measuring apparatus, the bottom surface was 0.020 μmRa and the side surface was 0.007 μmRa. It was confirmed that the surface roughness and flatness at the mirror surface level were obtained for both the surface and the side surface.

Comparative Example 1
A resin bond diamond cutting grindstone 1 having a diameter of 100 mm, a thickness of 0.25 mm, and # 2000 was attached to an outer peripheral cutting machine, and a cup tourer 4 which is a known truing tool having a GC 3000 and a cup grindstone 4 having a diameter of 90 mm was used. The conventional truing method was implemented in the form shown in FIG.
Using this cutting wheel that has been trued, a quartz glass plate as a work material is grooved at a feed rate of 2 mm / min in the same manner as in Example 1, and the surface roughness of the groove is measured with a laser probe type non-contact three-dimensional measuring device. As a result, the bottom surface and the side surface were both 0.10 μmRa, indicating that the truing method of the present invention was remarkably good.

The SEM photograph of the abrasive grain of the cutting grindstone outer periphery after truing of the present invention. The schematic diagram of the groove process by the grindstone which implemented the truing method by this invention. The schematic diagram of the conventional truing method using GC3000.

Explanation of symbols

1 Whetstone 2 Quartz glass plate 3 Groove 4 Cup truer

Claims (4)

A truing tool for diamond grindstones that uses a truing tool made of quartz glass as the main component, forms a smooth flat part at the tip of the abrasive grains dispersed in the bond, and aligns the height of the abrasive cutting edges. Method. By using a truing tool made of quartz glass as the main component and grinding the truing tool with a diamond grindstone used for cutting and grooving, the height of the abrasive cutting edge on the side of the grindstone is aligned and the wobbling on the side of the grindstone A method of truing a diamond grindstone characterized by removing 3. A truing method for a diamond grindstone according to claim 1, wherein the bond of the diamond grindstone is an organic type, and the abrasive cutting edge density is increased. A diamond grinding wheel truing tool made of quartz glass as the main component.