Patent ID: 8860077
Filing Date: 2014-10-14
Classification: H01L

Abstract:
1. A light emitting device, comprising: a substrate; a compound semiconductor layer including a plurality of semiconductor layers on a top surface of the substrate; a first conductive type semiconductor layer on a top surface of the compound semiconductor layer; a first electrode connected to the first conductive type semiconductor layer; a second conductive type semiconductor layer; a second electrode connected to the second conductive type semiconductor layer; and an active layer between the first conductive type semiconductor layer and the second conductive type semiconductor layer, wherein the first conductive type semiconductor layer comprises a first current spreading structure comprising at least one pair of a first conductive layer and a second conductive layer, a conductivity of the first conductive layer is higher than a conductivity of the second conductive layer, and the first current spreading structure is disposed in a sequence of the second conductive layer and the first conductive layer from the active layer, wherein the first conductive type semiconductor layer comprises a third conductive layer disposed between the compound semiconductor layer and the first current spreading structure, wherein the at least one pair of the first conductive layer and the second conductive layer is disposed between the third conductive layer and the active layer, wherein the third conductive layer has a dopant concentration between a dopant concentration of the first conductive layer and a dopant concentration of the second conductive layer, wherein the third conductive layer physically contacts a bottom surface of the first current spreading structure and a bottom surface of the first electrode, wherein the bottom surface of the first electrode is located at a position lower than an entire region of the first current spreading structure, wherein the third conductive layer is located at a position lower than the entire region of the first current spreading structure, wherein a conductivity of the third conductive layer is higher than the conductivity of the second conductive layer, wherein the first and third conductive layers have a difference of dopant concentration of about 1×10 wherein the first to third conductive layers comprise an N-type dopant, wherein the first to third conductive layers include different dopant concentrations from each other, wherein the second conductive layer has a thickness greater than a thickness of the first conductive layer, wherein the dopant concentration of the second conductive layer is about 1˜5×10 wherein the pair of the first conductive layer and the second conductive layer is stacked in cycles of about 2 to about 50.