Patent ID: 8872156

Claim:
A group III nitride semiconductor light emitting device comprising: an n-type cladding layer provided on a primary surface of a substrate, the n-type cladding layer comprising an n-type group III nitride semiconductor; an active layer provided on the primary surface of the substrate, the active layer comprising a group III nitride semiconductor; and a p-type cladding layer provided on the primary surface of the substrate, the p-type cladding layer comprising a p-type group III nitride semiconductor, the active layer being provided between the n-type cladding layer and the p-type cladding layer; the n-type cladding layer, the active layer, and the p-type cladding layer being arranged along a normal axis of the primary surface of the substrate; the p-type cladding layer being doped with a p-type dopant; the p-type cladding layer containing an n-type impurity; a concentration of the p-type dopant being greater than that of the n-type impurity; and wherein the p-type cladding layer comprises acceptor levels provided by the p-type dopant, the p-type cladding layer comprises donor levels provided by the n-type impurity, and the p-type cladding layer has a distribution of the donor levels and a distribution of the acceptor levels in a band gap energy of the p-type cladding layer, the distributions define a difference (E(BAND)−E(DAP)) between an energy E(BAND) of a band-edge emission peak value in a photoluminescence spectrum of the p-type cladding layer and an energy E(DAP) of a donor-acceptor pair emission peak value in the photoluminescence spectrum being not more than 0.42 electron volts, the energy E(BAND) of the band-edge emission and the energy E(DAP) of a donor-acceptor pair emission being represented in units of electron volts; a c-axis of the n-type group III nitride semiconductor of the n-type cladding layer tilting relative to the normal axis; a c-axis of the p-type group III nitride semiconductor of the p-type cladding layer tilting relative to the normal axis, and the p-type cladding layer contains hydrogen, and a hydrogen concentration of the p-type cladding layer is not more than 4×10 18 cm −3 .