Patent ID: 8455937

Claim:
A nonvolatile semiconductor memory device comprising: a semiconductor substrate; a memory cell including a first insulation film formed on the semiconductor substrate, a first gate electrode formed on the first insulation film, a second insulation film formed on an upper surface and a side surface of the first gate electrode, and a second gate electrode formed on the second insulation film; and a selection transistor including a third insulation film, a third gate electrode contacting to the third insulation film, a fourth gate electrode formed on the third gate electrode, a fourth insulation film formed on the fourth gate electrode, and a fifth gate electrode formed on the fourth insulation film, the third insulation film being formed on the semiconductor substrate, the fourth insulation film having an opening, and the fifth gate electrode contacting to the fourth gate electrode via the opening, wherein the second gate electrode includes a first portion, a second portion, and a third portion, the first portion is located directly above an upper surface of the second insulation film, the second portion is located on a side of the first portion and on a part of a side surface of the second insulation film, and the third portion is located on a remaining portion of the side surface of the second insulation film, wherein the first and second portions of the second gate electrode, the fourth gate electrode, and the fifth gate electrode are each formed of a silicide, the third portion of the second gate electrode and a portion which is in contact with the third insulation film of the third gate electrode are each formed of a silicon, and an undersurface of the fourth gate electrode is lower than an undersurface of the fourth insulation film.