| 摘要 |
PURPOSE:To obtain an insulated oxide film free from peripheral projection by forming a concave section in an epitaxial layer, which is converted at the part therof under the concave section into an oxide film by heat treatment and covered on the periphery of the side wall thereof with an oxidation resisting film when the epitaxial layer grown on a semiconductor substrate is isolated like islands with the oxide film. CONSTITUTION:An N type layer 11 is epitaxially grown on a P type Si substrate 10 and with a photoresist as mask, an etching is made to form several inclined concave sections 12 in the layer 11. Then, after an buffer oxide film 13 is produced on the entire surface of the layer 11 including the concave section by heat treatment, an Si3N4 film 14 is grown as oxidation resisting film on the film 13. A photolithography is conducted to remove the bottom part of the film 14 leaving a part thereof from the inclined side wall of the concave section 12 to the surface thereof thereby exposing the film 13. Thereafter, with the film 14 left as mask, a heat treatment is conducted to convert the epitaxial layer under the film 13 into an SiO2 film 16 whereby the layer 11 adjacent thereto is isolated like islands. Accordingly, the existence of the film 14 prevents the generation of any projection at the end of the film 16. |
