Patent ID: 6265285
Filing Date: 2001-07-24
Classification: H01L

Abstract:
A method of forming a self-aligned trench isolation on a semiconductor substrate with a pad oxide thereon, the method comprising the steps of:depositing a silicon film on said pad oxide;selectively removing said silicon film to expose said pad oxide, leave a residue silicon film, and form a first opening in said residue silicon film;forming a poly-oxide layer covered on said residue silicon film and a second opening between said poly-oxide layer;selectively removing said poly-oxide layer and pad oxide to form a poly-oxide spacer and expose said semiconductor substrate through said second opening;forming a trench extending into said semiconductor substrate through said second opening;depositing a dielectric film to fill in said trench and second opening;selectively removing said dielectric film to expose said residue silicon film; andremoving said residue silicon film.