PURPOSE: To grow a wurtzite type III nitride mixed crystal on a crystal having different crystal structure regarding a wide-gap semiconductor capable of being deposited on a semiconductor substrate.

CONSTITUTION: A semiconductor mixed crystal 2 composed of a first component and a second component is deposited on a semiconductor single crystal substrate 1 having zincblende type or diamond type crystal structure. The first component consists of one or two or more of compounds in AlN, GaN and InN, and the second component is made up of one or two or more of compounds in InP, GaP, AlP, InAs, GaAs, AlAs, InSb, GaSb and AlSb. The composition ratio of a first compound to a second compound is represented by a composition, in which the mean interatomic distance of a tetrahedron coordinate bond formed by group V atoms in the crystal structure of the semi-conductor mixed crystal 2 is equalized approximately to the interatomic distance of a tetrahedron coordinate bond formed in the crystal structure of the semiconductor crystal substrate 1.