Patent ID: 6680225
Filing Date: 2004-01-20
Classification: H01L

Abstract:
A method of manufacturing a semiconductor device, comprising:forming a gate insulating film on a surface of a semiconductor substrate; forming a mask structure on the gate insulating film, the mask structure exposing a first area of the gate insulating film and including a stop film and further including a through hole exposing a second area of the gate insulating film; forming side walls in the through hole, the side walls extending from the gate insulating film up to the stop film, but not extending to a top of the through hole; using the mask structure and the side walls as a mask, simultaneously doping an impurity into first and second regions of the substrate beneath the first and second areas of the gate insulating film exposed by the mask structure to produce drain and source regions; removing at least a portion of the second area of the gate insulating film; forming a tunnel insulating film where the portion of the second area of the gate insulating film was removed; and forming a gate structure above the gate insulating film.