Patent ID: 7949026

Claim:
A group III nitride semiconductor laser comprising: a substrate having a main surface; an n-type cladding layer provided on the substrate and composed of a group III nitride semiconductor; a p-type cladding layer provided on the substrate and composed of a group III nitride semiconductor; an active layer provided between the n-type cladding layer and the p-type cladding layer; a first optical guiding layer provided between the n-type cladding layer and the active layer; and a second optical guiding layer provided between the p-type cladding layer and the active layer, wherein the active layer includes a plurality of well layers and at least one first barrier layer provided between the well layers, the first optical guiding layer includes a first InGaN region composed of InGaN that has a band gap smaller than a band gap of the first barrier layer and larger than a band gap of the well layers, the second optical guiding layer includes a second InGaN region that is composed of InGaN, among the well layers of the active layer, a well layer that is closest to the first optical guiding layer is a first well layer, among the well layers of the active layer, a well layer that is closest to the second optical guiding layer is a second well layer, and the active layer includes a second barrier layer provided between the first well layer and the first optical guiding layer, and a third barrier layer provided between the second well layer and the second optical guiding layer.