Nonvolatile semiconductor memory device, method of fabricating the nonvolatile semiconductor memory device and process of writing data on the nonvolatile semiconductor memory device

摘要

A nonvolatile semiconductor memory device includes a semiconductor substrate, a plurality of first element isolation insulating films formed on a surface of the semiconductor substrate corresponding to a first cell array region into a band shape, a plurality of second element isolation insulating films formed on a surface of the semiconductor substrate corresponding to a second cell array region into a band shape. Each first element isolation insulating film has a level from a surface of the semiconductor substrate, the first charge storage layer has a level from the surface of the semiconductor substrate, and each second element isolation insulating film has a level from the surface of the semiconductor substrate, the level of each first element isolation insulating film being lower than the level of the first charge storage layer and higher than the level of each second element isolation insulating film.