Patent ID: 6027983
Filing Date: 2000-02-22
Classification: H01L

Abstract:
A method of manufacturing a semiconductor integrated circuit device, comprising:a step of forming a field insulating film in a semiconductor substrate having a surface;a step of forming in the semiconductor substrate a first groove for trench isolation with an aspect ratio of greater than 1, wherein the first groove is formed through the field insulating film and into the semiconductor substrate such that a first opening portion of the first groove, through the field insulating film, is tapered, at a first angle relative to the surface of the semiconductor substrate, and the first groove has a second opening portion into the semiconductor substrate, a taper angle of the second opening portion, relative to the surface of the semiconductor substrate, being greater than the first angle;a step of burying a first silicon oxide film in the first groove, and removing a part of the first silicon oxide film in such a way that a second groove, shallower than said first groove, with an aspect ratio of not greater than 1, remains; andafter said removing a part of the first silicon oxide film, a step of burying a second silicon oxide film into the second groove, so as to fill the second groove, such that the first groove is filled with only the first and second silicon oxide films.