| 摘要 |
PROBLEM TO BE SOLVED: To improve reliability of a semiconductor device having a split-gate MONOS memory.SOLUTION: A method for manufacturing a semiconductor device comprises the steps of: sequentially forming an ONO film and a polysilicon film P2 so as to fill a gap between a polysilicon film P1 and a dummy gate electrode; removing the dummy gate electrode; and polishing top faces of the polysilicon films P1 and P2 to form a memory gate electrode composed of the polysilicon film P2 on a sidewall of a control gate electrode composed of the polysilicon film P1 via the ONO film. As a result, the memory gate electrode having high perpendicularity of the sidewall and uniform film thickness is formed.SELECTED DRAWING: Figure 11 |
