| 摘要 |
PROBLEM TO BE SOLVED: To obtain a semiconductor device in which the film thickness of an oxide film is increased easily and selectively in the small number of processes so as to make the oxide film uniform, by a method wherein a halogen is contained under the surface of a polysilicon layer or a semiconductor substrate which is adjacent to the oxide film and the oxide film is grown by a heating treatment. SOLUTION: A field SiO2 film 2 is formed selectively on the surface of a P-type silicon substrate 1, a silicon nitride film and the SiO2 film are then etched so as to be removed, the surface of the substrate 1 is exposed, and gate oxide film 3 is deposited on its exposed face. In addition, a polysilicon layer 20 is deposited on the whole face of the gate oxide film 3 by a CVD method. Then, a resist mask 24 is applied, fluorine ions 21 as a halogen are implanted into the polysilicon layer 20 which is not covered with the resist mask 24, and the gate oxide film 3 is grown by a heating treatment so as to increase its film thickness. Thereby, the gate oxide film 3 can be made uniform. |
