NITRIDE SEMICONDUCTOR DEVICE AND METHOD FOR MANUFACTURING THE SAME, AND DIODE AND FIELD EFFECT TRANSISTOR

摘要

PROBLEM TO BE SOLVED: To suppress deterioration of current collapse and make a nitride semiconductor device have low ON resistance by suppressing diffusion of impurities forming an acceptor level.SOLUTION: A nitride semiconductor device comprises: a semiconductor laminated body having a superlattice structure where a substrate 11, a buffer layer 12, an electron transit layer 13 provided on the buffer layer 12, and nitride semiconductor layers having different Al composition ratios are laminated several times, and an electron supply layer 14 having a bandgap averagely being wider than that of the electron transit layer 13 and an etching sacrificial layer 15; a nitride semiconductor body provided on the semiconductor laminated body and having a bandgap averagely being narrower than that of the electron supply layer 14; a spacer layer 16 containing p-type impurities forming an acceptor level; and a semiconductor layer 17. An impurity concentration of the spacer layer 16 decreases from a boundary at the semiconductor layer 17 along a film thickness direction, toward a boundary at the etching sacrificial layer 15.