Abstract: A light emitting device, according to one embodiment, may comprise: a substrate having a pattern part disposed on the upper surface thereof; a first buffer layer disposed on the substrate; a second buffer later disposed on the first buffer layer; a first conductive semiconductor layer disposed on the second buffer layer; an active layer disposed on the first conductive semiconductor layer; a second conductive semiconductor layer disposed on the active layer; and a void layer disposed on the first buffer layer corresponding to the pattern part of the substrate. By further forming a void on the buffer layer, the embodiment has the effect of more effectively preventing defects caused by a potential difference.

Abstract: A light emitting device, according to one embodiment, may comprise: a substrate; a first conductive semiconductor layer disposed on the substrate; an active layer disposed on the first conductive semiconductor layer and generating an ultraviolet light; a second conductive semiconductor layer disposed on the active layer; and a hole injection layer disposed between the active layer and the second conductive semiconductor layer and comprising a first layer comprising AlxGa1-xN (0<x?1) and a second layer comprising GaN. The embodiment has the hole injection layer to be multi-layered, thereby having the effect of effectively preventing the absorption of ultraviolet light.

Abstract: A light emitting device, according to one embodiment, may comprise: a substrate having a pattern part disposed on the upper surface thereof; a first buffer layer disposed on the substrate; a second buffer later disposed on the first buffer layer; a first conductive semiconductor layer disposed on the second buffer layer; an active layer disposed on the first conductive semiconductor layer; a second conductive semiconductor layer disposed on the active layer; and a void layer disposed on the first buffer layer corresponding to the pattern part of the substrate. By further forming a void on the buffer layer, the embodiment has the effect of more effectively preventing defects caused by a potential difference.

Abstract: A light emitting device, according to one embodiment, may comprise: a substrate; a first conductive semiconductor layer disposed on the substrate; an active layer disposed on the first conductive semiconductor layer and generating an ultraviolet light; a second conductive semiconductor layer disposed on the active layer; and a hole injection layer disposed between the active layer and the second conductive semiconductor layer and comprising a first layer comprising AlxGa1-xN (0<x?1) and a second layer comprising GaN. The embodiment has the hole injection layer to be multi-layered, thereby having the effect of effectively preventing the absorption of ultraviolet light.

Abstract: Disclosed are a light emitting device, a method of manufacturing the light emitting device, a light emitting device package and a lighting system. The light emitting device includes a silicon substrate; a nitride buffer layer on the silicon substrate; and a gallium nitride epitaxial layer on the nitride buffer layer, wherein the nitride buffer layer includes a first nitride buffer layer having a first aluminum nitride layer on the silicon substrate and a first gallium nitride layer on the first aluminum nitride layer.

Abstract: A light emitting device includes a light emitting structure including a first conductive type semiconductor layer, an active layer and a second conductive type semiconductor layer; a multi-contact layer disposed on at least a predetermined region of the second conductive type semiconductor layer, the multi-contact layer including at least one pair-structure configured of a first layer including InGaN having a dopant doped thereon and a second layer including GaN having a different dopant doped thereon; and a first electrode and a second electrode to provide currents to the first conductive type semiconductor layer and the second conductive type semiconductor layer, respectively.

Abstract: Disclosed are a light emitting device, a method of manufacturing the light emitting device, a light emitting device package and a lighting system. The light emitting device includes a silicon substrate; a nitride buffer layer on the silicon substrate; and a gallium nitride epitaxial layer on the nitride buffer layer, wherein the nitride buffer layer includes a first nitride buffer layer having a first aluminum nitride layer on the silicon substrate and a first gallium nitride layer on the first aluminum nitride layer.

Abstract: A light emitting device includes a light emitting structure including a first conductive type semiconductor layer, an active layer and a second conductive type semiconductor layer; a multi-contact layer disposed on at least a predetermined region of the second conductive type semiconductor layer, the multi-contact layer including at least one pair-structure configured of a first layer including InGaN having a dopant doped thereon and a second layer including GaN having a different dopant doped thereon; and a first electrode and a second electrode to provide currents to the first conductive type semiconductor layer and the second conductive type semiconductor layer, respectively.