| 摘要 |
PURPOSE:To use a polycrystalline silicon film or a metallic silicide film as an electrode by forming an insulating film as a dielectric for an MIS type capacitor in three layer film structure of a first silicon dioxide, a tantalum oxide film and second silicon dioxide. CONSTITUTION:An element isolation region 22 consisting of silicon dioxide is shaped to a P-type silicon substrate 21 through a selective oxidation method, and a natural oxide film in several Angstrom on the P-type silicon substrate 21 and a tantalum oxide film 24 on the element isolation region 22 are formed through a reactive sputtering method. Oxygen passes through the tantalum oxide film 24 through oxidation in dry oxygen at 800 deg.C, the main surface of the P-type silicon substrate 21 is oxidized, and a first silicon dioxide film 23 in film thickness of approximately 20Angstrom is shaped. A second silicon dioxide film 25 is formed onto the surface of the tantalum oxide film 24, and annealed, polycrystalline silicon is deposited, and phosphorus is doped, thus shaping an electrode 26. The insulating films composed of three layers are used as a dielectric, thus preventing the reaction of polycrystalline silicon in the electrode 26 and tantalum oxide, then removing the limitation of an electrode material. |
