METHOD FOR MANUFACTURING SEMICONDUCTOR SUBSTRATE, AND SEMICONDUCTOR DEVICE

摘要

PROBLEM TO BE SOLVED: To provide: a method for manufacturing a semiconductor substrate which enables the improvement of a GaN layer in crystal quality; and a semiconductor device arranged by use of the semiconductor substrate.SOLUTION: A method for manufacturing a semiconductor substrate 1 comprises the steps of: growing an AlN layer 3 on a substrate 2; growing an AlGaN layer 4, of which the content of Al is 3.5-9%, on a surface 3a of the AlN layer 3 with Group III gas and Group V gas; growing a GaN layer 5 having a thickness of 250-1400 nm on a surface 4a of the AlGaN layer 4 with Group III gas and Group V gas; and growing an electron-supply layer 6 on the GaN layer 5. The supply of Group III gas is suspended for a length of time included in a range of 80-220 seconds after the growth of the AlGaN layer 4, but before the growth of the GaN layer 5.