Patent ID: 8648381

Claim:
A semiconductor light emitting device, comprising: an n-type semiconductor layer including a nitride semiconductor; a p-type semiconductor layer of GaN; a light emitting portion provided between the n-type semiconductor layer and the p-type semiconductor layer and including a plurality of a quantum well layers, each of the quantum well layers including a nitride semiconductor; a first layer provided between the light emitting portion and the p-type semiconductor layer, the first layer including Al x1 Ga 1-x1 N, where first Al composition ratio x 1 is an atomic ratio of Al among group III elements, the first Al composition ratio x 1 being not lower than 0.001 and not higher than 0.05, the first layer having a thickness not smaller than 0.5 nanometer and not larger than 5 nanometer; a second layer provided between the first layer and the p-type semiconductor layer, the second layer contacting the p-type semiconductor layer, the second layer including Al x2 Ga 1-x2 N, where second Al composition ratio x 2 is an atomic ratio of Al among group III elements, the second Al composition ratio x 2 being not lower than 0.1 and not higher than 0.2, a concentration of a p-type impurity in the second layer being higher than a concentration of a p-type impurity in the first layer; and an intermediate layer provided between the first layer and the light emitting portion, the intermediate layer contacting a p-side quantum well layer, the p-side quantum well layer being closest to the p-type semiconductor layer among the plurality of quantum well layers, the intermediate layer having a thickness not smaller than 3 nanometers and not larger than 8 nanometers and including In z1 Ga 1-z1 N, where In composition ratio z 1 is an atomic ratio of In among group III elements, the In composition ratio z 1 being not lower than 0 and lower than 1.