JPS6350336A - Method for molding glass - Google Patents

Abstract

PURPOSE:To easily obtain a glass target without air bubbles and contamination by pouring fused glass onto any of substrates such as BN plate, BN coated metallic plate and fluoroplastic coated metallic plate and molding the glass. CONSTITUTION:Any of the BN plate, the BN coated metallic plate and the fluoroplastic coated metallic plate having the good parting characteristic from glass is used as the substrate. The above-mentioned substrate is preheated preferably at slow cooling temp. of the glass and while the substrate is held at said temp., the fused glass is poured thereon to form the glass molding. The above-mentioned molding is subjected to a post treatment preferably at the temp. above the softening point to relieve strains. The glass target which does not contain air bubbles and contamination and does not splinter at the time of sputtering is thus obtd. without cracking and seizure during the prepn.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a method of manufacturing a glass target used for sputtering and the like.

BACKGROUND OF THE INVENTION With recent advances in film thinning technology, various oxides have come to be used as sputter targets. Glass is one such example, and sputtering is used to form an adhesive layer with a predetermined thickness when bonding ceramics, ferrite, and the like.

Conventionally, glass targets have been made by pouring molten glass into a mold made of cast iron, stainless steel, etc. and leaving it to cool, but this often results in cracking or burning to the substrate during manufacture, making it difficult to release from the mold. In order to prevent this, methods such as preheating the substrate and applying oil on the mold are used, but even then, the crackling still occurs, and when the glass is poured, the oil and fat evaporate and get stuck in the glass. It may get mixed in and create bubbles,
Carbonized oil and fat were contaminating the glass. Furthermore, the resulting glass remained distorted during cooling, and as a result, the target was subject to a rapid temperature rise during sputtering, which often caused it to break.

Problems to be Solved by the Invention The present invention solves the above problems by using a substrate that has good mold releasability from glass, preheating it to an appropriate temperature, and performing post-alpha treatment at an appropriate temperature. This is a point-resolution method.

Means for resolving the problem The present invention uses any one of a boron nitride plate, a metal plate coated with boron nitride, and a metal plate coated with a fluorine resin as a substrate with good mold releasability from glass. In addition to preheating this to the slow cooling temperature of glass, the obtained target is post-treated at a temperature higher than the softening temperature? Features.

Effect: According to the method of the present invention, a glass target that is free from bubbles and contamination can be easily obtained without cracking or burning during production.

Example Embodiments of the present invention will be described below while comparing them with conventional examples.

The present invention will be explained using an example in which a target with a diameter of 100 mm is manufactured.

(Example 1) An example of producing a Pyrex (Corning Corporation N117740) glass target will be described.

On a boron nitride substrate (for example, manufactured by Denki Kagaku Kogyo Co., Ltd., product number N-1, size 160 x 150 x 10 JEm) preheated to the slow cooling temperature of glass (about 560°C),
After melting the Pyrex glass in a platinum crucible at 1500°C, it was heated to 110°C to 12°C.
It was cooled to 0°C, poured into the ring, and allowed to stand. Place the obtained target together with the substrate in an electric furnace,
The temperature was raised from 560'C to above the softening temperature (e.g. 860°C) over a period of 1 hour, held at 850'C for 1 hour, and then allowed to cool in an electric furnace.The target obtained in this way did not burn into the substrate. No bubbles or impurities in the glass?
It contained no particles at all, and also did not crack during sputtering.

(Example 2) A substrate coated with boron nitride was prepared as follows.

After degreasing and sandblasting one side of a stainless steel plate of size 150 x 160 x 10, sprayed with boron coating S (manufactured by Denki Kagaku Kogyo Co., Ltd.) and heated at 800'C for 2 hours.
Baked for 0 minutes. Target 7) was obtained in the same manner as in Example 1 except that this substrate was used. The properties of the obtained target were similar to those in Example 1.

(Example 3) Glass for ferrite sealing (Corning Co., Ltd. 8463)
An example of creating a target will be explained.

A substrate coated with a fluororesin was prepared as follows.

After degreasing and sandblasting one side of a stainless steel plate measuring 150 x 160 x 101 m, coated with fluororesin D.
-1 (manufactured by Daikin Industries, Ltd.) was sprayed, 38
Baking was performed at 0°C for 20 minutes.

A 1100M stainless steel ring is placed on the substrate that has been preheated to the glass annealing temperature (approximately 320'C), and the glass is heated to 900'C in a platinum crucible, then heated to 600~800°C.
It was cooled to 'C, poured into the ring and left to stand. Placed in an electric furnace together with the obtained target substrate, and heated for 32 hours.
The temperature was raised from 0°C to above the softening temperature (for example, 400'C) in half an hour, held at 400°C for 1 hour, and then allowed to cool in an electric furnace. The target thus obtained had excellent releasability from the substrate, contained no bubbles or impurities in the glass, and did not break during sputtering.

(Conventional Example 1) In Example 1, a stainless steel plate was used as the substrate without preheating. When glass was poured on top of this, some parts of the substrate and glass were baked, and the parts that weren't baked cooled down quickly, causing the target to crack irregularly.

(Conventional Example 2) In Example 1, a stainless steel plate coated with mineral oil was preheated to 660° C. and used as a substrate. When glass was poured over this, the mineral oil burned and air bubbles and carbide were mixed into the glass. Seizure of the substrate and glass still occurred, and the target was broken.

(Conventional Example 3) In Example 1, after the glass was poured into the ring, preheating was stopped and the glass was allowed to cool. The target thus obtained remained distorted due to the difference in cooling rate between the surface and the surface in contact with the substrate, which caused cracks during sputtering.

(Conventional Example 4) In Example 1, the base material was preheated at a temperature below the slow cooling temperature (for example, 350'C). This result was similar to Conventional Example 1.

(Conventional Reli 5) In Example 1, the post-treatment temperature was set below the softening temperature of glass (for example, 700'C), and the results were the same as in Conventional Example 3.

Effects of the Invention As described above, according to the method of the present invention, it is possible to easily obtain a glass target/feet without cracking or burning during production, without bubbles or contamination, and without cracking during sputtering. Can be done.

Claims (3)

[Claims] (1) Glass characterized in that a glass molded body is obtained by pouring molten glass onto a substrate such as a boron nitride plate, a metal plate coated with boron nitride, or a metal plate coated with fluororesin. molding method. (2) The method for molding glass according to claim 1, characterized in that the substrate is preheated to an annealing temperature of glass. (3) The glass molding method according to claim 1 or 2, characterized in that the glass molded body is post-treated at a temperature higher than its softening temperature.