Patent ID: 8076685

Claim:
A nitride semiconductor device comprising: an n-type cladding layer formed on a substrate; an active layer formed on the n-type cladding layer; a current confining layer formed on the active layer and having a recess portion; and a p-type cladding layer formed on the current confining layer, wherein the current confining layer includes a first semiconductor layer, a second semiconductor layer formed on and in contact with the first semiconductor layer, and a third semiconductor layer formed on and in contact with the second semiconductor layer, the second semiconductor layer has a smaller lattice constant than a lattice constant of the first semiconductor layer, the third semiconductor layer has a lattice constant that is smaller than the lattice constant of the first semiconductor layer and larger than the lattice constant of the second semiconductor layer, and the recess portion of the current confining layer from which parts of the third semiconductor layer and the second semiconductor layer are removed serves as a conductive area through which a current flows to the active layer, and is configured so that the recess portion passes through the third semiconductor layer and a portion of the second semiconductor layer such that the recess portion does not extend completely through the second semiconductor layer.