Semiconductor light emitting device

Abstract

According to one embodiment, a semiconductor light emitting device includes a first conductivity type semiconductor layer, a light emitting layer and a second conductivity type semiconductor layer. The first conductivity type layer has a superlattice structure. First semiconductor layers and second semiconductor layers are alternately provided in the superlattice structure. The first semiconductor layers include a first nitride semiconductor and the second semiconductor layers include a second nitride semiconductor having a larger lattice constant than the first nitride semiconductor. The light emitting layer has a multi-quantum well structure. Quantum well layers and barrier layers are alternately provided in the multi-quantum well structure. The quantum well layers include a third nitride semiconductor having a smaller lattice constant than the second nitride semiconductor and the barrier layers include a fourth nitride semiconductor having a smaller lattice constant than the third nitride semiconductor. At least one of the quantum well layers has lattice spacing equal to the lattice constant of the third nitride semiconductor.