COMPOUND SEMICONDUCTOR AND SEMICONDUCTOR DEVICE

PROBLEM TO BE SOLVED: To reduce the occurrence of crystal defect, i.e., dislocation in a compound semiconductor layer in a compound semiconductor wherein lattice mismatching between a substrate and the compound semiconductor layer formed on the substrate is ≥2%. SOLUTION: In the compound semiconductor 1 where a buffer layer 3 and the compound semiconductor layer 4 are formed on the substrate 2, lattice mismatching of the buffer layer 3 to the substrate 2 is changed stepwise with respect to the thickness of the buffer layer, i.e., a plurality of buffer constitution layers are provided. Consequently, the crystal defect is reduced by selecting the thickness of the buffer constitution layer. COPYRIGHT: (C)2005,JPO&NCIPI