Patent ID: 6333232
Filing Date: 2001-12-25
Classification: H01L

Abstract:
A method of manufacturing a semiconductor device comprising steps of:(a) preparing a semiconductor substrate having a main surface;(b) forming a multilayer film including an oxide semiconductor film and a nitride semiconductor film located thereon on said main surface of said semiconductor substrate;(c) patterning said nitride semiconductor film thereby selectively forming an opening having a shape separating said main surface into a plurality of regions in said nitride semiconductor film;(d) executing etching through patterned said nitride semiconductor film employed as a mask thereby selectively removing a portion immediately under said opening at least until said main surface of said semiconductor substrate is exposed;(e) oxynitriding a surface located under said nitride semiconductor film and exposed in a cavity formed immediately under said opening;(f) executing etching through patterned said nitride semiconductor film employed as a mask thereby forming a trench in a portion of said semiconductor substrate immediately under said opening;(g) forming an inner wall insulator film including an oxide semiconductor film coming into contact with an inner wall of said trench on said inner wall;(h) filling said trench with an insulation after said step (g);(i) removing said multilayer film at least after said step (g); and(j) forming a component of a semiconductor element in each of said plurality of regions separated from each other by said trench in said main surface of said semiconductor substrate.