| 摘要 |
According to one embodiment, a nonvolatile semiconductor memory device includes memory transistors, an interlayer insulating film, a peripheral transistor and a sidewall. The memory transistors are formed on a semiconductor substrate. Each of the memory transistors includes a first stack gate which includes a floating gate electrode, a second gate insulating film, and a control gate electrode. The interlayer insulating film is formed between the first stack gates. The interlayer insulating film includes a first air gap. The peripheral transistor is formed on the substrate. The peripheral transistor includes a second stack gate which includes a first gate electrode, a third gate insulating film, and a second gate electrode. The sidewall is formed on a side surface of the second stack gate and includes a second air gap. An upper end of the second air gap is located at a position lower than the third gate insulating film. |
