| 摘要 |
PURPOSE:To avoid unnecessary electric field centralization and in addition to decreasing a leakage current, improve the dielectric strength by forming a tunnel insulating film and an erase electrode in sequence after forming a floating gate electrode on a silicon nitride film with a molecular beam epitaxy process. CONSTITUTION:A channel cut and field insulating film 2 and a gate insulating film 3 are formed on a semiconductor substrate 1 and a silicon nitride film 4 is formed on the above film 2. And a floating gate electrode 5 consisting of a poly silicon film is formed on the insulating film 3 and the nitriding film 4 with a molecular beam epitaxy process. Subsequently, a tunnel insulating film 6 is formed around the electrode 5 and a control electrode 9 is formed on the above film 6 and also an erase electrode is formed on the above film 6 which is placed on the film 4. Further, source and drain regions 7 and 8 are formed to obtain a floating gate type nonvolatile memory. In this way, surfaces of the electrode 5 and the insulating film 6 are so smooth that the surfaces are free of unnecessary electric field and improve the dielectric strength.
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