Nonvolatile semiconductor memory device

Abstract

A nonvolatile semiconductor memory device includes: a semiconductor region; device isolation regions placed in the semiconductor region and extending in a column direction; a semiconductor layer placed on the semiconductor region and between the device isolation regions, and having a convex shape in cross section along a row direction; source/drain regions placed in the semiconductor layer and spaced from each other; a gate insulating film placed on the semiconductor layer between the source/drain regions; a floating gate electrode layer placed on the gate insulating film; an intergate insulating film placed on the floating gate electrode layer and upper surfaces of the device isolation regions; and a control gate electrode layer placed on the intergate insulating film and extending in the row direction.