Patent ID: 6027977
Filing Date: 2000-02-22
Classification: H01L

Abstract:
A method of fabricating a semiconductor device, comprising the steps of:(a) forming a silicon nitride film on a semiconductor substrate;(b) ion-implanting oxygen into said silicon nitride film and by heat-treating said oxygen-implanted silicon nitride film, thereby forming an oxygen-doped silicon nitride film having an oxygen-rich region that extends along an interface between said oxygen-doped silicon nitride film and said substrate;said oxygen-rich region being higher in oxygen concentration than a remainder of said oxygen-doped silicon nitride film;at least part of said oxygen-doped silicon nitride film serving as a gate insulator film of a MISFET;(c) forming a gate electrode of said MISFET on said oxygen-doped silicon nitride film;(d) selectively introducing a dopant into said substrate to form a pair of source/drain regions of said MISFET in said substrate at each side of said gate electrode; and(e) heat-treating said substrate to activate said dopant introduced into said substrate in said step (d).