JPS6171954A - Grinding method with cup-shaped grinding wheel - Google Patents

Abstract

PURPOSE:To enhance the working effectiveness by performing grinding with the internal edge of a cup-shaped grinding wheel, and thereby efficiently processing the work to be ground made of a brittle substance such as wafer. CONSTITUTION:A grinding wheel 4 and a wafer 2 are located so that the wheel 4 surrounds the wafer 2, and the wheel 4 is moved in the direction of arrow B. At this time, the angle theta formed by the tangential line on the outside edge of the wafer 2, in the position where the wheel 4 cuts into the wafer 2, with respect to the tangential line on the internal edge 6 of the wheel 4 will be an obtuse angle. Therefore the outside edge of the after 2 is not likely to generation of cracks, so that the margin for grinding can be set a large value. Further, supply of the grinding liquid from the spindle 3 will provide adequate feed of the grinding liquid to the point to be ground, which will contribute to enhancement of working efficiency in grinding.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a grinding method using a cup-shaped grindstone, and particularly to a grinding method suitable for grinding objects to be ground made of brittle materials such as silicon wafers.

[Background of the invention]

For example, when surface-grinding the surface of a silicon wafer (hereinafter simply referred to as wafer), the surface is ground as shown in FIGS. 4 to 6.

In other words, a cup-shaped grindstone (hereinafter simply referred to as a grindstone) supported by the spindle 3 is attached to the wafer 2 held by the chuck 1.
4 is sent in the direction of arrow A, and grinding is performed with the outer peripheral edge 5 of the grindstone 4.

At this time, as shown in FIG. 6, if the angle θ formed by the tangent a to the outer peripheral edge of the wafer 2 at the cutting position of the grinding wheel 4 to the wafer 2 and the tangent to the outer peripheral edge 5 of the grinding wheel 4 becomes an acute angle,
Chips and cracks are likely to occur at the outer peripheral edge of the wafer 2. Also,
This tendency becomes more noticeable when the outer peripheral edge of the wafer 2 is chamfered C as shown in FIG. 5, or when the grinding allowance d is large. For this reason, if you reduce the amount of grinding per time and divide the grinding allowance d into several times,
This will reduce work efficiency.

Also, when supplying the grinding fluid to the grinding point, if the grinding fluid is supplied from the outside of the grinding wheel 4, or if the grinding fluid is shaken off by the centrifugal force due to the rotation of the grinding wheel 4, and then the grinding fluid is supplied from the inside of the grinding wheel 4. , the grindstone 4 becomes an obstruction and it is not possible to supply sufficient grinding fluid to the grinding point. For this reason, there was a drawback that the grinding had to be performed with reduced workability.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to provide a grinding method using a cup-shaped grindstone that eliminates the drawbacks of the prior art described above and enables grinding without reducing workability.

[Summary of the invention]

In order to achieve the above object, the present invention is characterized in that grinding is performed by an inner peripheral edge of a grindstone.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to the drawings.

1 to 3 show an embodiment of the present invention, in which a wafer 2 is fixed on a chuck 1. FIG. A grindstone 4 is supported at the lower end of the main shaft 3.

With this configuration, the grindstone 4 and the wafer 2 are positioned so that the grindstone 4 covers the wafer 2, and the grindstone 4 is rotated and moved in the direction of arrow B.

At this time, as shown in FIG. 3, the angle θ formed by the tangent a to the outer peripheral edge of the wafer 2 at the cutting position of the grindstone 4 to the wafer 2 and the tangent e to the inner peripheral edge 6 of the grindstone 4 becomes an obtuse angle. Therefore, chips and cracks are less likely to occur on the outer peripheral edge of the wafer 2, and the grinding allowance d can be increased.

Further, by supplying the grinding fluid from the main spindle 3, it is possible to sufficiently supply the grinding fluid to the grinding point, so that grinding can be performed without reducing workability.

〔Effect of the invention〕

As described above, according to the present invention, an object to be ground made of a brittle material such as a wafer can be efficiently ground, and workability can be greatly improved.

[Brief explanation of drawings]

FIG. 1 is a side sectional view showing an inner peripheral blade grinding method according to an embodiment of the present invention, FIG. 2 is an enlarged view of main parts showing the grinding state in FIG. 1, and FIG. FIG. 4 is a plan view, FIG. 4 is a side cross-sectional view showing a conventional peripheral blade grinding method, and FIG. 5 is a plan view. FIG. 4 is an enlarged view of the main part showing the grinding state, and FIG. 6 is a plan view of FIG. 5.

Claims (1)

[Claims] A workpiece to be ground and a cup-shaped grindstone having an inner diameter larger than an outer diameter of the workpiece are arranged so that the workpiece to be ground is located in the center of the cup-type grindstone, and the cup-type grindstone is A grinding method using a cup-shaped grindstone, which is characterized in that the cup-shaped grindstone is rotated, the cup-shaped grindstone and the object to be ground are moved relative to each other, and the object to be ground is ground with the inner peripheral edge of the cup-shaped grindstone.