Patent ID: 6798038
Filing Date: 2004-09-28
Classification: H01L

Abstract:
A semiconductor device comprising:a semiconductor substrate having a trench on a surface; an insulating film identified by a back face contacting with the surface of said semiconductor substrate and having a first opening on the trench; a polysilicon film disposed on a surface of said insulating film and having a second opening over the trench; a first silicon oxide film contacting with a bottom face and a side face of the trench and a side face of the first opening; a bottom insulator having a bottom face and a side face coming into contact with a surface of the first silicon oxide film; a second silicon oxide film identified by a back face contacting with said polysilicon film and identified by a surface contacting with said bottom insulator and identified by one end contacting with said insulating film and identified by a height of the other end being equal to that of an upper face of said bottom insulator; and an upper insulator identified by a bottom face contacting with the other end of said second silicon oxide film and the upper face of said bottom insulator and identified by a side face contacting with a side face of said polysilicon film.