SEMICONDUCTOR SUBSTRATE, MANUFACTURE THEREOF AND SEMICONDUCTOR DEVICE

PURPOSE:To obtain a semiconductor substrate by a pasting method which is suitable for manufacturing an element by a method wherein the plane orientation of main faces of a semiconductor crystal sheet and a semiconductor single-crystal thin film is a 100 plane and directions of inner-plane orientations of both are at mutually different angles. CONSTITUTION:At a semiconductor substrate in which a semiconductor single-crystal thin film 21 of a diamond-type crystal structure has been formed, via an insulator 24, on a semiconductor crystal sheet 22 having the same crystal structure, the plane orientation of main faces of the semiconductor crystal sheet 22 and the semiconductor single-crystal thin film 21 is a {100} plane; directions of inner-plane orientations of both are at mutually different angles. For example, two wafers whose surface is a 100 plane and which have orientation flats 23 in directions of and of Si wafers whose one face has been mirror-polished are prepared; oxide films whose thickness is 0.5mum are formed on their surface. The two wafers are piled up in such a way that mirror-polished faces are opposed. At this time, the orientation flats 23 are aligned. While the wafers are brought into close contact, they are heat-treated in a wet oxidizing atmosphere at 800 deg.C or higher. The oxide films between them are united and an insulating film 24 is formed.