Corrosion resistant structure for conductor and PSG layered semiconductor device

A semiconductor device comprising:

• a semiconductor substrate of one conductivity type,
• an oxide film formed on one main surface of said semiconductor substrate,
• drain and source regions of the conductivity type opposite to that of said semiconductor substrate formed in said semiconductor substrate adjoining said main surface,
• a first electrode formed on said oxide film and serving as a gate electrode,
• a phosphorous silicate glass layer formed on said first electrode and said oxide film and having a surface smoothed,
• a second electrode formed on said phosphorous silicate glass serving as contacts of said drain and source regions, and
• a nitride film formed on said phosphorous silicate glass layer, said second electrode and said oxide film,
• a scribing line being formed on said semiconductor substrate to encompass said semiconductor device,
• said oxide film extending to the vicinity of said scribing line,
• the end portion of said phosphorous silicate glass layer formed on said oxide film extending to the vicinity of said scribing line being positioned inside the end portion of said oxide film and the end portion of said nitride film being positioned on said oxide film between the end portion of said phosphorous silicate glass layer and said scribing line, said phosphorous silicate glass layer being completely covered through close contact of said nitride film with said oxide film.