Patent ID: 8592885

Claim:
A nonvolatile semiconductor memory device, comprising: a substrate including silicon and having an active area and an element-separating insulating film provided around the active area; a tunneling insulating film provided on the active area; a floating gate provided on the tunneling insulating film; a leak suppression unit provided on the floating gate; an inter-gate insulating film provided on the leak suppression unit; and a control gate provided on the inter-gate insulating film, the leak suppression unit provided to cover an upper surface of the floating gate and an upper portion of a side wall of the floating gate by extending beyond a corner formed by an upper surface of the floating gate meeting the side wall of the floating gate, and being provided apart from the element-separating insulating film, and a dielectric constant of the leak suppression unit being higher than a dielectric constant of the inter-gate insulating film.