Patent ID: 8295317

Claim:
A group III nitride semiconductor laser comprising: a GaN substrate having a primary surface; a first conductivity type group III nitride semiconductor layer provided on the GaN substrate; a second conductivity type of group III nitride semiconductor layer provided on the GaN substrate; and an active layer having multiple In x Ga 1-x N well layers and plural barrier layers, the active layer being provided on the GaN substrate, the active layer being provided between the first conductivity type group III nitride semiconductor layer and the second conductivity type group III nitride semiconductor layer, a molar ratio x of indium of the In x Ga 1-x N well layer is equal to or more than 0.32 and not more than 0.35, and wherein a distribution of indium content in the In x Ga 1-x N well layers has a maximum and a minimum, and the maximum and the minimum reside within a range from −15% to +15% of an average of the indium content in the well layers, and wherein the average of the indium content indicates the molar ratio x of, and wherein each well layer comprises a plurality of In x Ga 1-x N thin films, the plurality of In x Ga 1-x N thin films includes one In x Ga 1-x N thin film and another In x Ga 1-x N thin film, and the one In x Ga 1-x N thin film and the other In x Ga 1-x N thin film forms an interface.