Patent ID: 7629619

Claim:
A Group III nitride-based compound semiconductor light-emitting device having a quantum well, structure, the device comprising: a multiple quantum well layer comprising plural well layers each having the same composition ratio and plural barrier layers each having the same composition ratio; and plural interface regions formed between each of said plural well layers and each of said plural barrier layers, each interface region of the plural interface regions having the same composition distribution, wherein the plural barrier layers consist of Al x Ga 1·x N (0<x<1), and the plural well layers consist of In y Ga 1-y N (0<y<1), and wherein the plural interface regions consist of: a first part consisting of In y Ga 1-y′ N (0≦y′<1) positioned on a side of said interface regions which is nearest to said well layers, y′ continuously varying from y to 0 as a distance from the well layers increases; a second part consisting of Al x′ Ga 1-x′ N (0≦x′<1) positioned on a side of said interface regions which is farthest from said well layers, x′ continuously varying from 0 to x as a distance from the well layers increases; and a GaN region formed between the first part and the second part.