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:
Nov. 07, 1989
Filed:
Sep. 27, 1988
Hidetoshi Wakamatsu, Tokyo, JP;
Oki Electric Industry Co., Ltd., Tokyo, JP;
Abstract
A method for forming a smooth borophosphosilicate glass film on a semiconductor substrate is described, in which a semiconductor substrate having at least one stepped portion thereon is formed with one side of the substrate a borophosphosilicate glass layer having a defined boron content and a defined phosphorus content with a defined total content of the boron and phosphorus. The layer is subjected to thermal treatment under conditions of a temperature of not lower than 940.degree. C. and a time of not shorter than 15 minutes in an atmospheric gas supplied at a flow rate of not lower than 19 liters/minute. As a result, the BPSG glass layer is smoothed on the surface thereof without formation of undesirable grains on the surface. This thermal treatment is particularly suitable for fabrication of a semiconductor element or device using an insulating film of the borophosphosilicate glass.