A nonvolatile semiconductor memory device includes a floating gate electrode which is selectively formed on a main surface of a first conductivity type with a first gate insulating film interposed therebetween, a control gate electrode formed on the floating gate electrode with a second gate insulating...http://www.google.de/patents/US7985650?utm_source=gb-gplus-sharePatent US7985650 - Nonvolatile semiconductor memory device and method of manufacturing the same
