| 摘要 |
PURPOSE:To enable to form a stable surface protection film by a method wherein a single crystal Si is treated in a specific mixed gas resulting in the formation of a polycrystalline Si film, and thereafter heat-treated in a gas containing chlorine or chlorine compound and oxygen. CONSTITUTION:A single crystal Si semiconductor element whereon a P-N junction is formed is treated by an etching. Next, this Si semiconductor element is treated by an exposure in the mixed gas constituted of HF gas, NO2 gas and chlorine gas or chloring compound, and thus a polycrystalline Si film is formed on the surface of the Si semiconductor element by the reaction between the Si single crystal surface thereof and the mixed gas. Then, this Si semiconductor element is heat-treated at approx. 100 deg.C-500 deg.C for several min-several 10hr under the presence of the oxygen containing chlorine or chlorine compound, and accordingly at least the surface of the polycrystalline Si film is changed into a stable oxide film. Thereby, a surface protection film can be simply formed wherein the flat band density is small and extremely stabilized. |
