Patent ID: 7135380
Filing Date: 2006-11-14
Classification: H01L

Abstract:
1. A method for manufacturing a semiconductor device, comprising the steps of: forming a first insulating film on a surface of a semiconductor layer, the first insulating film having an opening provided in a desired region, and forming a groove in the semiconductor layer through the opening; forming a second insulating film so as to fill up the groove, and forming a trench from a surface of the second insulating film; forming a third insulating film on the second insulating film, forming a polycrystalline silicon film on the third insulating film, and filling the trench with the third insulating film and the polycrystalline silicon film; polishing the second insulating film, the third insulating film and the polycrystalline silicon film by use of the first insulating film as a stopper film; and forming an insulating spacer in a concave part formed by partially removing the third insulating film when the first insulating film is removed by etching.