| 摘要 |
PURPOSE:To dispense with providing a space between floating gates and raise the degree of integration, by oxidizing the floating gates insulated by an oxide film, making a polysilicon oxide film and growing a polysilicon at gas phase. CONSTITUTION:A field oxide film 2 is produced on a P-type substrate 1 by a selective oxidation film process. A gate oxide film 3 is then produced. A polysilicon film 4 is grown at gas phase. An impurity is diffused into the film 4 to make this film electroconductive. A part of the film 3 is removed except for only a polysilicon for making alternate cells. A gate oxide film 7 is produced on the substrate 1 and a polysilicon oxide film 8 is produced on the film 4. A polysilicon film 9 is grown on the films 7, 8 and made electroconductive. Unnecessary parts are removed so that the floating gates 4, 9 insulated by the oxide film 8 are provided. The films 4, 9 are oxidized so that a polysilicon oxide film 5 is produced. A polysilicon 6 is grown at gas phase. As a result, a space does not need to be provided between the floating gates and the degree of integration is raised. |
