JPS6436045A - Manufacture of semiconductor device - Google Patents

Abstract

PURPOSE:To manufacture a semiconductor having an SOI structure which suppresses leakage at an interface by a method wherein an insulating layer composed of CaF2 or SrF2 is deposited on a single-crystal silicon substrate, surface silicon is laminated, the surface of the substrate is melted by using a beam or by a heat treatment and three layers melted by a liquid growth method are made monocrystalline. CONSTITUTION:A surface region 4 of an Si substrate 1, an insulating film 2 and surface silicon 3 are melted by using an ion, an electron beam, a beam of light or thermal radiation; a crystalline insulating film 6 (composed of CaF2, SrF2, BaF2 or a mixture of these) and surface single-crystal silicon 7 are formed on the single-crystal silicon substrate 1 by a liquid growth method. According to this manufacturing method, an interface between a liquid phase and a single-crystal silicon phase at an initial stage of the growth operation is situated in the surface region of the substrate 1; a defect 5 caused during the liquid growth operation exists only in the substrate 1. Accordingly, the surface single-crystal layer 7 forming a device is composed of silicon having very nearly defect-free crystallinity. Because a lattice constant of the insulating crystal 6 is close to that of the single-crystal silicon 7 during the liquid growth operation, the mismatching at the interface between the layer 6 and the layer 7 can be suppressed.