Method for reducing the defect density of an integrated circuit utilizing ion implantation

Claim 1

In a method for reducing the defect density of an integrated circuit having a semiconductor substrate, a buried region and an epitaxial layer grown over said substrate and buried region, said epitaxial layer including a plurality of integrated devices occupying a predetermined extended area which is substantially coextensive with said buried region said method comprising the following steps: providing a semiconductor substrate having a surface; forming a grated mask on said surface having alternate elongated portions respectively covering and exposing said surface; forming a relatively thin, compared to said mask, protective layer; covering exposed portions of said surface by a thermal oxide growth technique in which a portion of said substrate is used up in the formation of the thin layer; ion-implanting conductivity determining impurities through said protective layers and into said semiconductor body to form a plurality of elongated regions; merging said elongated regions into a single region; and growing said epitaxial layer over said substrate and single region.