Method of manufacturing a semiconductor device and a semiconductor device obtained thereby

Claim 1

A method of manufacturing a semiconductor device according to claim 1, wherein silicon nitride is deposited from vapor phase on the surface of said glass layer to form a silicon nitride film and thereafter and silicon nitride film is subjected to boiling phosphoric acid with a silicon oxide film as a selective mask thereby to cover selectively the surface of said glass layer with said silicon nitride film.

Claim 2

A method of manufacturing a semiconductor device comprising the steps of: forming a silicon oxide layer on one major surface of a semiconductor substrate; covering said silicon oxide layer on said semiconductor substrate with a glass layer containing silicon oxide and an oxide of at least one of phosphorus, boron and lead; depositing a silicon nitride film on the entire top surface of said glass layer; forming a silicon dioxide layer having at least one hole therein the surface of said silicon nitride film; dipping said substrate into a boiling phosphoric acid solution and removing said silicon nitride film exposed by said hole, thereby exposing a surface of said glass layer underlying said silicon nitride film within said hole; and removing said glass layer and said silicon oxide layer through said hole to expose a surface of said semiconductor substrate by subjecting said exposed glass layer to an etchant of mainly hydrofluoric acid solution with said silicon nitride film as a selective mask.

Claim 4

A method of manufacturing a semiconductor device comprising the steps of preparing a semiconductor substrate, one major surface of which is covered by a doped glass layer; covering said glass layer with a silicon nitride film; selectively subjecting the exposed surface of said silicon nitride film to an etchant primarily affecting said silicon nitride film while leaving the glass layer substantially unaffected to constitute said silicon nitride film an etching mask for said glass layer; and thereafter selectively subjecting said glass layer to an etchant that leaves said silicon nitride film substantially unaffected so that said silicon nitride film forms an etching mask for said glass layer in the presence of said second-mentioned etchant.