US Patent 9768346 Light-emitting device

A light-emitting device and a lighting system includes a first conductivity type semiconductor layer, a gallium nitride-based super lattice layer on the first conductivity type semiconductor layer, an active layer, on the gallium nitride-based super lattice layer, a second conductivity type gallium nitride-based layer on the active layer, and a second conductivity type semiconductor layer, on the second conductivity type gallium nitride-based layer. The second conductivity type gallium nitride-based layer can include a second conductivity type AlxGa(1−x)N/AlyGa(1−y)N, such as AlxGa(1−x)N/AlyGa(1−y)N, on the active layer.