| 摘要 |
A decease in reliability of a memory element having a floating gate is suppressed. The invention relates to a semiconductor device having an island-like semiconductor film, which is formed over an insulating surface and includes a channel formation region and a high-concentration impurity region, a tunneling insulating film formed over the island-like semiconductor film, a floating gate formed over the tunneling insulating film, a gate insulating film formed over the floating gate, a control gate formed over the gate insulating film, and a first insulating film formed between the tunneling insulating film and the floating gate. The first insulating film is formed of an oxide film of the material of the floating gate, so that the material of the floating gate is prevented from diffusing into the tunneling insulating film. |
