Method for producing group iii nitride semiconductor and template substrate

Abstract

The present invention provides a method for producing a Group III nitride semiconductor. The method includes forming a groove in a surface of a growth substrate through etching; forming a buffer film on the groove-formed surface of the growth substrate through sputtering; heating, in an atmosphere containing hydrogen and ammonia, the substrate to a temperature at which a Group III nitride semiconductor of interest is grown; and epitaxially growing the Group III nitride semiconductor on side surfaces of the groove at the growth temperature. The thickness of the buffer film or the growth temperature is regulated so that the Group III nitride semiconductor is grown primarily on the side surfaces of the groove in a direction parallel to the main surface of the growth substrate. The thickness of the buffer film is regulated to be smaller than that of a buffer film which is employed for epitaxially growing the Group III nitride semiconductor on a planar growth substrate uniformly in a direction perpendicular to the growth substrate. The growth temperature is regulated to be lower than a temperature at which the Group III nitride semiconductor is epitaxially grown on a planar growth substrate uniformly in a direction perpendicular to the growth substrate. The growth temperature is preferably 1,020 to 1,100° C. The buffer film employed is an AlN film having a thickness of 150 Å or less.