NITRIDE SEMICONDUCTOR DEVICE AND NITRIDE SEMICONDUCTOR MANUFACTURING METHOD

摘要

A nitride semiconductor device includes a first III nitride semiconductor layer and a second III nitride semiconductor layer. The first III nitride semiconductor layer has a V/III ratio, i.e., a ratio of the nitrogen material (molar ratio) to the III element material (more specifically, gallium material), at a prescribed ratio of first V/III, and has a growing main plane other than a c-plane. The second III nitride semiconductor layer is arranged on the first III nitride semiconductor layer, has a second V/III ratio higher than the first V/III ratio, and has the growing main plane same as that of the first III nitride semiconductor layer.