Planar semiconductors prodn. using double insulating film - comprising oxide and nitride on (silicon) substrate as mask for etching recess

摘要

In the prodn. of a planar semiconductor, a double insulating film of a substrate oxide (pref. SiO2) layer and a substrate nitride (pref. Si3N4) layer is formed in the surface of a semiconductor (pref. Si) substrate; recesses are etched in the substrate surface, using the double film as mask; the substrate surface with the overlying mask is oxidised thermally so that an oxide film is formed in the recesses; the double insulating film is etched away; and the surface of the insulating oxide film is etched. The depth of the recesses and the thickness of the insulating film pref. are selected so that the surface of the insulating film can be levelled by etching. The semiconductor has a planar surface on which multilayer wiring is possible. It can be integrated easily and is free from breaks in the wiring and in the insulating film.