SEMICONDUCTOR DEVICE

摘要

PURPOSE:To prevent generation of compressive stress to be caused by noncoincidence of lattice interval of a semiconductor device by a method wherein impurities having sufficiently deep energy level to convert a silicon semiconductor layer into a semiisulating layer are implanted in the silicon semiconductor layer. CONSTITUTION:The second conductive type impurities having sufficiently deep energy level to convert a first conductive type silicon semiconductor layer 11 into a semiinsulating layer and to compensate for free carriers are implanted in the silicon semiconductor layer 11 to form the semiinsulating silicon layer 12. When the semiconductor device is to be used using liquid nitrogen as refrigerant, the energy level of impurities is made to be separated by 0.2eV or more from the conductive band to be formed according to the type conductive carriers.