JPS61215259A - Manufacture of silicon nitride target for sputtering - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method for manufacturing a silicon nitride target used when forming a protective film by sputtering.

(Prior art) Conventionally, silicon nitride targets are manufactured by sintering.
In order to provide sinterability, it is common to add several percent of ittria or calcium oxide for sintering.

(Problems to be Solved by the Invention) ゛When used to form a protective film tube on a substrate by sputtering a target layer containing yttoria, etc. as described above,
Disadvantages such as the protective film becoming colored or poor adhesion occur. Furthermore, itria is expensive and has the disadvantage that a cheap silicon nitride target cannot be obtained.

In order to improve these drawbacks, it has been proposed to manufacture the target by a reactive sintering method, but the drawback still remains that unreacted silicon inhibits the formation of a protective film.

The object of the present invention is to solve these drawbacks and provide a manufacturing method for obtaining a silicon nitride target that is inexpensive and has good film formation properties.

(Means for Solving the Problems) In the present invention, silicon nitride and silicon dioxide powders are mixed in a weight ratio of 70=30 to 9585, and then fired.

(Function) Silicon dioxide, which has a common element (silicon) f: silicon nitride, acts as a binder, and both t? 70:30
The silicon nitride target obtained by mixing and firing at a ratio of 95:5 has a lower density than the conventional target made by adding itria or calcium oxide to silicon nitride and firing it, but it is a target made by the reaction sintering method. Almost the same density was obtained, and the sinterability was relatively good.

Furthermore, the silicon nitride target according to the present invention had sufficient sputtering power and a satisfactory 01 sputtering rate. Furthermore, the thin film formed was not colored, and its performance as a protective film was the same as that of a conventional target mixed with itria or the like.

(Example) Examples of the invention are as follows.

Example 1 70 parts of silicon nitride powder and 30 parts of silicon dioxide powder were mixed, and the mixture was put into a mold and sintered. Results of measuring the density of the test piece thus obtained Table 1
As shown in FIG. 2, the density of LsF/i was lower than that of the conventionally manufactured test piece according to Comparative Example 1, which will be described later, but was approximately equal to the density of the conventionally manufactured test piece according to Comparative Example 2.

Furthermore, a target of 4 inches in diameter and 6M in thickness was attached.
After metal bonding was carried out under certain conditions, the film formation rate was measured and the adhesion and coloring of the formed film were observed with the naked eye.
/h)/(VA/d), a colorless protective film with good adhesion was obtained.

Example 2 80 parts of silicon nitride powder and 0 parts of silicon dioxide powder were mixed together, and the mixture was placed in a mold and sintered. As a result of measuring the density of the test piece obtained by this method, as shown in Table 1, z2/c! t was not much different from the case of Comparative Example 2 described later. Furthermore, the diameter is 4 inches and the thickness is 6IIJl.
After metal bonding of the target under certain conditions, the film formation rate was measured, and the adhesion and coloring of the formed film were observed with the naked eye. As shown in Table 2, it was the same as in Example 1. Ta.

Example 3 95 parts of silicon nitride powder and 5 parts of silicon dioxide powder were mixed and sintered into a mold.

The density measurement results for the test piece obtained by this ELK are shown in Table 1, and it has a diameter of 4 inches and a thickness of 61 m.
After metal bonding was performed on the target under certain conditions, the film formation rate was measured, and the adhesion and coloring were observed with the naked eye. The results were the same as in Example 1 as shown in Table 2.

Comparative Example 1 A test piece was formed by the conventional manufacturing method of mixing 95 parts of silicon nitride powder, 3 parts of oxidizing lucium powder, and 2 parts of ittria powder, and sintering the mixture into a mold.The density of the test piece was measured. It is shown in Table 1.

Sara〈About a target with a diameter of 4 inches and a thickness of 6 mm,
After metal bonding was performed under certain conditions, the film formation rate was measured, and the adhesion and coloring of the formed film were observed with the naked eye. The results are shown in Table 2.

Comparative Example 2 The density of a test piece manufactured by a conventionally known reaction sintering method in which metal silicon powder is placed in a mold and reacted with nitrogen gas under high temperature conditions is 2.4 r/d as shown in Table 1. can be,
Similar to Comparative Example 1, a target rattler with a diameter of 4 inches and a thickness of 61 mm was prepared, and the diameter and film formation rate of the metal bonding were measured under constant nf conditions, and the adhesion and coloring of the formed film were observed with the naked eye. The results are shown in Table 2.

Table 1 Density table of silicon nitride test piece Table 2 Film formation rate, thin film characteristics and coloring by silicon nitride target (effects of the invention) As described above, in the present invention, silicon nitride and silicon dioxide powders are Since the silicon nitride target for sputtering is produced by mixing at a weight ratio of 70:30 to 95:5 and then firing, a target with good sintering properties is obtained at low cost. The resulting protective film is colorless and free of free silicon protrusions, and has a good film formation rate, allowing for rapid formation of a good protective film.

Claims (1)

[Claims] Silicon nitride and silicon dioxide powder at a weight ratio of 70:3
A method for producing a silicon nitride target for sputtering, which comprises mixing at a ratio of 0 to 95:5 and then firing.