| 摘要 |
PURPOSE:To obstruct invasion of field oxide films into an active region of a semiconductor device by a method wherein the first mask layer is provided on the surface of a semiconductor substrate, oxide films are formed on both the sides thereof being buried slightly in the surface of the substrate, the surface layer parts thereof are removed to expose the surface of substrate at the edge parts of the first mask, and the field oxide films are made to grow covering the exposed parts with the second masks. CONSTITUTION:An SiO2 film 12 and an Si3N4 film 13 are made to cause vapor growth epitaxially being laminated on the semiconductor substrate 11, and the unnecessary parts are removed to form the first oxidation resistive mask 14 consisting of the films 13, 12. Then heat treatment is performed to form the oxide films 15 on both sides of the mask 14 being buried slightly in the substrate 11, and thickness of the films 15 is made thin to expose the substrate 11 at the edge parts of the mask 14 to form films 16. Then SiO2 films 17 to constitute the second masks are formed by thermal oxidation at the parts 11a of the substrate 11 exposed at the edge parts of the films 16, and after then, the thick oxide films 18 are made to generate in the substrate 11 on both sides of the first mask 14. Accordingly the device is highly integrated. |
