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:
Jan. 26, 1988
Filed:
Feb. 06, 1987
Masakazu Kakumu, Yokohama, JP;
Sigeru Morita, Toyko, JP;
Kabushiki Kaisha Toshiba, Kawasaki, JP;
Abstract
A method of manufacturing a semiconductor substrate, and, in particular, a technique of electrically isolating a semiconductor element formed on a semiconductor substrate. The method comprises the steps of depositing a silicon oxide layer on the surface of a silicon substrate, for its protection; forming a silicon nitride layer on the silicon oxide layer; selectively eliminating the silicon nitride layer; oxidizing the silicon substrate, with the retained silicon nitride layer being used as a mask, thereby providing an oxide layer; depositing a polycrystalline silicon layer on the oxide layer and the retained acid-resisting layer; oxidizing the polycrystalline silicon layer to provide an insulation layer; eliminating the insulation layer until the silicon nitride layer is exposed; and removing all the silicon nitride layer. The method is capable of enabling the formation of a thick semiconductor element-isolating oxide layer, with a high precision, in a narrow region from which the semiconductor element is to be isolated.