| 摘要 |
PURPOSE:To enhance the insulating property in the electric field intensity resistance of a polycrystalline silicon interlayer oxide film by heat treating a polycrystalline silicon layer, to which high density impurity is introduced in an oxygen atmosphere and diffusing an impurity, thereby decreasing the resistivity of said silicon layer. CONSTITUTION:A gate oxidized film 3 and a field oxidized film 2 are formed on a silicon single crystal substrate 1, the first polycrystalline silicon layer first polysilicon layer 4 is formed on the film 2, and phosphorus, arsenic or boron of high density is ion implanted as impurity. A heat treatment (oxygen drive-in) is performed in oxygen atmosphere, and high density impurity is diffused in the first polysilicon layer 4. A thin silicon oxide film 7 formed on the surface is removed, and a silicon oxide film (polysilicon interlayer oxidized film) 5 is formed. A polycrystalline silicon layer (second polysilicon layer) 6 is grown, phosphorus, arsenic or boron of high density is diffused as impurity. |
