| 摘要 |
PURPOSE:To obtain the highly integrated insulation in isolating substrate by selectively forming polycrystal nucleus on a semiconductor substrate, growing a single crystal layer and a polycrystal layer, oxidizing the surface of the single crystal layer and the polycrystal layer, forming a supporting layer thereon, and thereafter grinding and removing the semiconductor substrate. CONSTITUTION:Silicon oxide film pattern 21 which is to become polycrysal part is formed on the surface of the silicon substrate 20. Thereafter, the polycrystal layer 22 is deposited on the pattern 21 by the epitaxial growth, and the single crystal layer 23 is likewise deposited on the other part. Then the surfaces of the single crystal layer 23 and the polycrystal layer 22 are oxidized and a silicon oxide film 21' is formed. The part of the polycrystal layer 22 in the film 21' is etched away. When this part is treated by a positive electrode in fluoric acid and oxidized, the polycrystal layer 22 is perfectly oxidized and a silicon dioxide layer 21'' is obtained. Then a polycrystal silicon layer 24 which is to become the supporting layer is deposited, and the silicon substrate 20 is ground and removed. Thus the insulation isolating substrate is obtained. The surface area of the silicon dioxide layer for isolation is small. |
