| 摘要 |
PURPOSE:To simplify processes, by using flattening by application of silicate glass and a polycrystalline silicon oxidie method, forming a groove-embedded- element isolating region, thereby reducing damage of the element. CONSTITUTION:A silicon substrate 1 is thermally oxidized, and a thin thermal oxide film 3 is formed on the surface. Then a polycrystalline silicon film 4 is grown by using a vapor phase growing method, and a groove part is completely buried. At this time, since the polycrystalline silicon film 4 is grown on the part, where the groove is not present, a recess 5 is formed at the upper part of the groove. In order to reduce the irregularities due to the recess, liquid state silicate glass 6 is applied and dried. Then, thermal oxidation is performed in a high-temperature oxidizing atmosphere, and the polycrystalline silicon, which is located at the part other than the groove, is all oxidized. By oxidizing the silicon, an upper end surface 9 on the polycrystalline silicon 8, which is embedded in the groove, is made to become the same height as a surface 10 of the silicon substrate other than the groove. The silicate glass formed in this way and the thermal oxide film of the polycrystalline film are etched by using a solution (e.g., dilluted fluoric acid). Thus, the silicon surface 10 other than the groove (element region) is exposed. |
