The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 23, 1991
Filed:
May. 11, 1990
Hisashi Fukuda, Tokyo, JP;
Oki Electric Industry Co., Ltd., Tokyo, JP;
Abstract
In a method of forming an insulating film on a substrate wherein a substrate is cleaned by heating it in an atmosphere of a reducing gas, and heating it in an oxidizing gas, and then growing an insulating film by heating the substrate in an atmosphere of a gas used to grow the film in the same reaction chamber, the insulating film is grown in stages and an insulating film grown in each stage is crystallized by heat treatment with a temperature higher than the heat treatment for the film growth. This can be accomplished by interposing a heat treatment with the higher temperature between successive film growth stages, or by using a higher temperature for the film growth for each stage with a temperature higher than that for the film growth in the preceding stage.