| 摘要 |
PURPOSE:To provide a semiconductor device capable of obtaining preferable charge holding characteristics by forming the first gate of a polysilicon film and forming the thickness of the film three to eight times of the thickness of an interlayer oxidized film. CONSTITUTION:When the first layer polysilicon film 4 is thinner than an oxidized film 5, the end is reduced in thickness, the polysilicon film 6 of the second layer is crept to the lower side, but when the film 4 becomes thick, the end becomes round, and the coverage of the second polysilicon film 6 is preferable. When the thickness of the first polysilicon film 4 is formed three to eight times that of the film 5, excellent withstand voltage characteristic of the film 5 can be obtained, thereby improving the memory holding characteristics of the product of a 32K bit FAMOS semiconductor device having 3,500Angstrom . The ratio of the thickness of the film 6 to the film 4 is important in the writing characteristic. |
