| 摘要 |
PURPOSE:To improve the controllability of an element separating process as well as to improve the electric characteristics of the interface between an oxide film and a silicon substrate by a method wherein a silicon layer is deposited only in the groove which is covered by an insulating film, and said silicon layer is converted to a silicon oxide film by performing a selective oxidization. CONSTITUTION:A thermally oxided film 23 and a silicon nitride film 24 are deposited on the surface of a silicon substrate, a polycrystalline silicon layer 25 is deposited in an aninotropic manner. Then, the silicon layer 25 is left on the plane surface only by performing an etching. A resist film 26 is coated on the whole surface, an etching is performed thereon, the bottom part only of the recessed groove is left, an etching is performed again on the polycrystalline silicon layer 25 under the above-mentioned condition, and the bottom part only of the layer 25 is left. Then, the structure wherein the groove is filled up to the depth of about one half of its depth is formed using an epitaxial growing technique selectively. Subsequently, after a phosphorus diffusion has been performed, the structure wherein the recessed groove is filled up with silicon oxide is formed by totally oxidizing the polycrystalline silicon layer 25 using a hydrogen combustion oxidizing method, for example, and then an etching is performed on the silicon nitride film and the silicon oxide film.
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