Nonvolatile semiconductor memory device, fabricating method thereof and operation method thereof

摘要

A nonvolatile semiconductor memory device has a cell which includes a drain diffusion region and a source diffusion region formed on a surface layer of a semiconductor substrate; a first insulating film formed between the source diffusion region and the drain diffusion region; a floating gate formed on the first insulating film; a second insulating film formed on the floating gate; a first control gate formed on the second insulating film; a third insulating film formed on the first control gate and a sidewall thereof and on a sidewall of the floating gate; and a second control gate formed on the first control gate with the third insulating film interposed therebetween.