Semiconductor device and manufacturing method of semiconductor device

摘要

A semiconductor device of the present invention has a first insulating film (3) formed between a control gate electrode (CG) and a semiconductor substrate (1) and a second insulating film (5) formed between a memory gate electrode (MG) and the semiconductor substrate and between the control gate electrode and the memory gate electrode, the second insulating film having a charge accumulating part therein. The second insulating film has a first film (5A), a second film (5N) serving as a charge accumulating part disposed on the first film, and a third film (5B) disposed on the second film. The third film has a sidewall film (5s) positioned between the control gate electrode and the memory gate electrode and a deposited film (5d) positioned between the memory gate electrode and the semiconductor substrate. In this structure, the distance at a corner part of the second insulating film can be increased, and electric-field concentration can be reduced.