Patent ID: 8227790

Claim:
A Group III nitride semiconductor light-emitting device comprising: a substrate; and a light-emitting layer having a multiple quantum well structure comprising a barrier layer, which is provided on a surface of the substrate and formed of a Group III nitride semiconductor, and a well layer formed of an indium-containing Group III nitride semiconductor, wherein the light-emitting layer having the multiple quantum well structure is constituted by stacking a plurality of multilayer portions which comprise one unit multilayer portion comprising the well layer and the barrier layer or two or more stacked unit multilayer portions, in the respective multilayer portions, the barrier layers of the unit multilayer portions are different in thickness, in the light-emitting layer, the multilayer portions are arranged from the surface side of the substrate toward a direction of taking out light emitted by the light-emitting layer in the order that the multilayer portion emits lights of shorter wavelength, and when the multilayer portion comprises two or more unit multilayer portions, the respective well layers or the respective barrier layers have the same thickness and composition.