| 摘要 |
PURPOSE:To enable the formation of a gate insulation film excellent in characteristic of dielectric strength having a high dielectric constant by a method wherein, after formation of a double-layer structure of an oxide film and a nitride film, a thin oxide film is formed by oxidizing the surface of the nitride film by heat treatment in an oxidizing atmosphere. CONSTITUTION:An Si oxide film 3 is formed on the surface of a semiconductor substrate 1 by thermally oxidizing the Si single crystal substrate 1 as the semiconductor substrate in the atmosphere of dry oxygen or wet oxygen. An Si nitride film 4 is deposited on the oxide film 3. A thin Si oxide film 5 is formed by thermally oxidizing the surface of the nitride film 4 by heat treatment in an oxidizing atmosphere such as the atmosphere of wet oxygen or dry oxygen, resulting in the formation of a three-layer structure of oxide film 3/nitride film 4/oxide film 5. Then, it is heat-treated in an inert gas atmosphere. An electrode material 6 of poly Si containing impurities such as phosphorus, arsenic, and boron; a high melting point metal such as molybdenum, tungsten, or titanium or their silicide; a metal such as aluminum or the like is deposited on the Si oxide film 5. |
