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:
May. 28, 1991
Filed:
Sep. 26, 1988
Nippondenso Co., Ltd., Kariya, JP;
Abstract
A method of manufacturing a semiconductor apparatus having a plurality of elements formed on a substrate comprises forming a pad oxidized film on the surface of the semiconductor substrate, forming a pattern of silicon nitride film to coat device areas on the pad oxidized film, and injecting boron ions into that surface of the pad oxidized film where no silicon nitride film is present, thereby to form a channel stopper region. Using the pattern of the silicon nitride film as a mask, a heat oxidized film is then formed on an elements separating region by heat oxidization, and ions of Si, N, C, or the like are injected into the surface of the heat oxidized film with such an acceleration energy that the ions are not injected into the silicon nitride film thereby to change the quality of the heat oxidized film. The silicon nitride film is removed by etching and the heat oxidized film is etching-treated by a solution of the hydrofluoric acid group to etching-remove particularly the bird's beak portions each of which is present along and under the peripheral rim of an element area of the silicon nitride film.