JPH0590404A - Method and apparatus for cutting chip - Google Patents

Abstract

PURPOSE:To shorten the time for manufacturing a chip and to prevent the breakdown of an edge at the time of surface cleaning by performing the cutting and the chamfering of a wafer at the same time. CONSTITUTION:Cover glasses 3 for protecting the polished surfaces are fixed to both surfaces of a wafer 4, which is finished by optical polishing, with a bonding agent. The wafer 4 is machined in a chip shape with a cutting wire saw 1 having the V-shaped cutting blade (a). V-shaped grooves 6 and 7 are formed in both surfaces of the wafer 4. When the wafer is cut apart, a chamferred chip 5 is obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a square and chamfered chip from a crystal wafer when processing a solid-state laser oscillator from an oxide crystal, and a chip cutting device used in this method. Regarding

[0002]

2. Description of the Related Art Conventionally, when cutting a crystal wafer, an Nb: YVO ₄ single crystal (hereinafter abbreviated as NYV) is used to confirm a plane orientation suitable for laser oscillation by X-ray measurement, and then a diamond wire saw is used for cutting. Speed 0.5mm
/ Min, a wafer having a thickness of 1.5 mm is cut while adding cooling oil to the cut surface.

Then, the surface precision λ /
After 10 mm or less (λ6328 nm) and parallelism within 10 seconds, optical polishing with a thickness of 1 mm is performed, and then the chips are cut into 3 mm square chips with a thickness of 1 mm by a dicing machine device.

[0004]

In a laser oscillation NYV chip, a hard coat suitable for a laser oscillation wavelength and a non-reflective coating film for excitation light are generally formed on a surface which is optically polished.

At this time, the polishing surface must be coated without dust, oil film, scratches, abrasives, etc.

However, if the chip surface is not chamfered by the cleaning for cleaning the chip surface, a cotton swab or the like used for the surface cleaning is caught at the edge portion, the edge is chipped, and the polishing surface is scratched. Since the cleaning tends to be incomplete, the adhesive strength of the coating film is weakened, which causes peeling. For this reason, conventionally, the chips have been chamfered as a post-treatment after cutting.

An object of the present invention is to provide a chip cutting method and device that solve the above problems.

[0008]

In order to achieve the above object, in a chip cutting method according to the present invention, a cutting wire saw is used to perform cutting and chamfering simultaneously to cut a rectangular chip from a wafer. The cutting method includes a step of forming a groove having a V-shaped cross section on the corresponding both surfaces of the wafer, and a step of cutting the wafer into chips between the V-shaped grooves.

The chip cutting device is a chip cutting device having a wire saw for cutting a wafer, and the wire saw has a cutting edge with a V-shaped cross section, and fine diamond particles are embedded on the surface of the cutting edge. It is embedded.

[0010]

When the wafer is cut between the grooves, chamfered square chips are obtained.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

The point of the tip cutting device of the present invention is the shape of a wire saw for cutting, and its cross section has a V-shaped cutting edge in which diamond 2 is embedded in the surface of the wire saw 1 as shown in FIG. Have.

The tip cutting device of the present invention has a length of 10 m.
Attach the wire saw 1 of so that the cutting surface does not shake to the left and right.

Next, as shown in FIG. 2A, a thickness of 0.3 m is formed on both surfaces of the wafer 4 optically polished to a thickness of 1 mm.
After fixing the cover glass 3 of m with an adhesive, it is fixed on the sample mounting base of the diamond wire saw in the direction in which the largest number of chips can be obtained, and then cutting is performed.

In FIG. 2B, in the cutting process, one surface of the processed wafer is A and the back surface is B. First, with respect to the surface A, the moving speed of the wire saw 1 is 10 m / min.
The cutting speed into the sample is 0.1 mm / min, and it is 0.8
When the depth of mm is reached, the next cutting is started, the sample is moved in parallel at 3 mm intervals, the sample table is rotated 90 degrees at the place off the wafer, and the same operation as described above is performed again to form the V-shaped groove 6 on the A side. 3
It is formed into a square of mm square.

When the surface A is finished, the processed wafer is turned upside down, cutting is started at the same position and distance as the surface A with the surface B facing upward, the same operation is performed, and the V-shaped groove 7 is formed. The chamfered chip 5 shown in FIG. 2B can be manufactured. After a square of 3 mm square is formed on all A and B sides of the processed wafer, the cover glass 3 is removed by washing with an organic solvent, and it is confirmed that the chip surface is free of dust, oil film, scratches, and adhesive impurities. Then store in a sealed container.

[0017]

According to the present invention, it is possible to improve the non-defective rate by eliminating the time required for the total chamfering after cutting and reducing the factors that damage the polished surface.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a wire saw used in the device of the present invention.

FIG. 2A is a state in which a cover glass is attached to the wafer, and FIG. 2B is a sectional view of the cut wafer.

[Explanation of symbols] 1 wire saw 2 diamond 3 cover glass 4 wafer 5 chip 6,7 V-shaped groove

Claims (2)

[Claims] 1. A chip cutting method for cutting a rectangular chip from a wafer by simultaneously performing cutting and chamfering using a cutting wire saw, wherein a groove having a V-shaped cross section is formed on both corresponding surfaces of the wafer. And a step of separating the wafer into chips between the V-shaped grooves. 2. A chip cutting device having a wire saw for wafer cutting, wherein the wire saw has a V-shaped cutting edge, and fine diamond particles are embedded in the surface of the cutting edge. A chip cutting device characterized by the above.