Patent ID: 8598644

Claim:
A nonvolatile semiconductor storage device, comprising: a semiconductor substrate including a first region and a second region; a gate insulating film formed in the first region and the second region; a first transistor formed above the gate insulating film in the first region and comprising a first gate electrode including a charge storage layer, an interelectrode insulating film, and a control electrode layer, the first gate electrode being isolated from one another; a second transistor formed above the gate insulating film in the first region so as to be located adjacent to the first transistor, the second transistor comprising a second gate electrode including a lower electrode, an upper electrode, and an upper silicide portion above the upper electrode; and a third transistor formed above the gate insulating film in the second region and comprising a third gate electrode including a lower electrode, an upper electrode, and an upper silicide portion above the upper electrode; wherein the lower electrodes of the second and the third gate electrodes have a first side and a second side taken along a length direction of the second and the third gate electrodes, the lower electrodes of the second and the third gate electrodes including a lower silicide portion in which at least the first side of the lower electrodes are partially silicided.