Patent ID: 7084422

Claim:
A semiconductor light emitting device comprising: (i) a support substrate made of a first semiconductor material; (ii) a light emitting lamination structure disposed on the support substrate, the light emitting lamination structure comprising: a quantum well layer made of a second semiconductor material; a pair of carrier confinement layers made of a third semiconductor material having a band gap wider than a band gap of the second semiconductor material, said pair of carrier confinement layers sandwiching the quantum well layer; and a pair of clad layers made of a fourth semiconductor material having a band gap wider than the band gap of the third semiconductor material, said pair of clad layers sandwiching the pair of carrier confinement layers; wherein a composition of the second semiconductor material, a composition of the third semiconductor material, and thicknesses of the quantum well layer and the carrier confinement layers are set such that light emission recombination of electrons and holes occurs in the quantum well layer and light emission recombination does not occur in the carrier confinement layers when current flows through the light emitting lamination structure; and (iii) electrodes for injecting carriers into the light emitting lamination structure.