| 摘要 |
PURPOSE:To prevent the generation of a bird's beak as well as to obtain a high integration by a method wherein an oxide film pattern is provided in a selective oxide region, and after a nitriding film has been selectively formed by heating a substrate in NH3 using the oxide film as a mask, a selective oxidizing treatment is performed. CONSTITUTION:The prescribed pattern, consisting of a thermal oxide film 6 (600Angstrom ) is formed on the substrate 1. Then, the above is heated in the NH3 atmosphere of 1,100 deg.C and the nitriding film 7 (1,300Angstrom in thickness, for example) is formed in such a manner that it is deeper than the oxide film by 200Angstrom or more. Subsequently, an oxidizing treatment is performed in the atmosphere of steam of 1,100 deg.C, for example, and an oxide film 8 of approximately 6,000Angstrom is selectively formed on the substrate through oxide film 6. Through these procedures, as the nitriding film 7 is directly covering the substrate 1 and functioning as an oxidation-resistant mask, the generation of the lateral spreading (bird's beak) on the selective oxide film 7 can be prevented. Besides, the oxide film 6 can be selectively oxidized by removing it after a nitriding treatment has been performed. |
