| 摘要 |
PURPOSE:To enable to perform excellent characteristics of a non-volatile semiconductor memory by forming an extremely thin gate insulating film region which transfers charge by tunnel effect between a floating gate and an impurity region at the prescribed distance from the end of a field insulating film, thereby eliminating the irregular characteristics between the elements of an informing rewriting region. CONSTITUTION:An n<+> type layer 28 formed continuously to a source 22 is formed adjacent to a channel region, a floating gate 25 is extended on the region, and the second control gate 31 made of polycrystalline or metal which is capacitively coupled to the gate 25 is formed by insulating them via gate insulating films 26, 30. An extremely thin gate insulating film 29 on an n<+> type layer 28 of an information rewriting region is formed on the region isolated at a distance from th end of a field insulating film 32, and a gate insulating film 33 of thickness of the degree which does not produce tunnel effect is formed on the region between the film 32 and the film 29. |
