A light-emitting semiconductor device provides an active layer which comprises thirteen (13) layers that includes six (6) pairs of quantum barrier layers made of Al.sub.0.95In.sub.0.05N and quantum well layers made of Al.sub.0.70In.sub.0.30N, which are laminated together alternately. The semiconductor device may also comprise a quantum well layer having a high composition ratio of indium (In). Forming the quantum barrier layer and the quantum well layer to have a high composition ratio of indium (In) increases the lattice constant of the active layer of the semiconductor device.