| 摘要 |
A method of manufacturing of a semiconductor device having a thermal oxidation process for selectively forming an oxide film by a thermal oxidation, which can reduce the generation of lattice defects in the semiconductor device during the thermal oxidation process. A groove portion LOCOS oxide film is formed in a groove portion of a semiconductor substrate by first and second wet oxidation steps. At the first wet oxidation step, a thin oxide film is formed on an exposed surface of an epitaxial layer by performing a wet oxidation through an opening portion made of silicon nitride under an oxidation temperature of approximately 875° C. At the second wet oxidation step, the oxidation temperature is risen to approximately 1050° C. to advance the oxidation of the epitaxial layer to finally form the groove portion LOCOS oxide film having a thickness of approximately 950 nm. Lattice defects due to the dislocation is reduced by largely releasing the thermal stress generated at the semiconductor substrate portion corresponding to the edges of the groove portion LOCOS oxide film. Therefore, it can reduce the generation of lattice defects in the semiconductor device during the thermal oxidation process.
|
