Patent ID: 8648384

Claim:
A light emitting device comprising a light emitting structure comprising: a first semiconductor layer; a second semiconductor layer; an active layer disposed between the first semiconductor layer and the second semiconductor layer; and undoped Al y Ga 1-y N (0<x≦1) disposed between the active layer and the second semiconductor layer, wherein the first semiconductor layer is an N type semiconductor layer doped with an N type dopant, the second semiconductor layer is a P type semiconductor layer doped with a P type dopant, the active layer comprises at least one pairs of alternately stacked well layers and barrier layers, one of the barrier layers adjacent to the second semiconductor layer comprises a first layer and a second layer disposed between the first layer and the second semiconductor layer, the first layer has a first band gap, the second layer has a second band gap, the second band gap is less than the first band gap, the second layer is doped with a P type dopant, wherein the first layer and the second layer include In, and the second layer has In content greater than that of the first layer.