Patent ID: 6255218
Filing Date: 2001-07-03
Classification: H01L

Abstract:
A fabrication method of a semiconductor device comprising the steps of:(a) selectively forming an oxidation-resistant film on a surface of a semiconductor substrate of a first conductivity type;(b) thermally oxidizing said substrate using said oxidation-resistant film as a mask, thereby forming selectively a field insulator film in a surface area of said substrate;(c) selectively removing said field insulator film using said oxidation-resistant film as a mask until the top of said resultant field insulator film is lower than said surface of said substrate, thereby forming a first insulating subregion;(d) forming a second insulating film to cover said first insulating subregion;(e) selectively removing said second insulating film to thereby form a second insulating subregion on said first insulating subregion;said first insulating subregion and said second insulating subregion constituting an isolation insulator defining an active region in the surface area of said substrate;(f) selectively forming a conductive region of a second conductivity type in said active region to be contacted with said isolation insulator;said second conductivity type being opposite to said first conductivity type;(g) forming an interlayer insulating film to cover said active region and said isolation insulator;said interlayer insulating film being different in material from said second insulating subregion;(h) forming a contact hole in said interlayer insulating film to expose said conductive region by a selective etching process;said process having an etch rate for said interlayer insulating film greater than that for said second insulating subregion; and(i) forming a patterned interconnection film on said interlayer insulating film to be contacted with said conductive region through said contact hole.