| 摘要 |
PURPOSE:To improve the element characteristics any yield while equalizing the shape especially depth of a single crystal island by a method wherein the mechanical polishing process after P type epitaxial growing process is performed utilizing anisotropic etching solution. CONSTITUTION:Parts of a P type single crystal island 5, a transition region 6 and polycrystalline Si 7 are removed by means of etching, a P type epitaxially grown substrate 1 (Fig. a) utilizing KOH water solution conforming to the conventional procedures to control precisely making the height of an N type single crystal island 2 and that of P type single crystal island 5 equivalent utilizing an SN oxide film 4 as a stop layer (Fig. b) An Si nitride film 13 and the Si oxide film 4 are grown and another Si oxide film 14 and the Si nitride film 13 are selectively formed and then the transistor region 6 and the polycrystalline Si 7 are anisotropically etched utilizing the films 14 and 13 as masks to form a V-shaped groove. (Fig. c) Next the Si oxide film 14 and the Si nitride film 13 are successively removed and a P<+> buried layer 9 is formed on a part of the P type single crystal island 5 and then a separating oxide 10 is formed. (Fig. d) Later a complementary dielectric isolation substrate may be formed by means of performing said procedures (Fig. d). |
