Light emitting device and light emitting device package including the same

Abstract

Provided are a light emitting device and a light emitting device package including the same. The light emitting device comprises a first conductive type semiconductor layer, an active layer comprising a plurality of quantum well layers and a plurality of barrier layers, which are alternately laminated on the first conductive type semiconductor layer, and a second conductive type semiconductor layer on the active layer. The plurality of barrier layers comprise a plurality of first barrier layers comprising a conductive type dopant, and the conductive type dopant doped into the plurality of first barrier layers have different doping concentrations for each layer.

1 . A light emitting device comprising:
 a first conductive type semiconductor layer;   an active layer including plurality of quantum well layers and plurality of barrier layers alternately laminated on the first conductive type semiconductor layer; and   a second conductive type semiconductor layer on the active layer,   wherein the plurality of barrier layers comprise plurality of first barrier layers in which a conductive type dopant is doped and the conductive type dopant doped into the plurality of first barrier layers has different doping concentrations for each layer,   the plurality of barrier layer comprise at least one second barrier layer in which the conductive type dopant is not doped,   the at least one second barrier layer is disposed adjacent to one of the first conductive type semiconductor layer and the second conductive type semiconductor layer,   the plurality of first barrier layers are disposed adjacent to the other one of the first conductive type semiconductor layer and the second conductive type semiconductor layer, and   wherein the plurality of first barrier layers have a doping concentration of a relatively high concentration of the conductive type dopant as the first barrier layer becomes close to the at least one second barrier layer.   
     
     
         2 . The light emitting device according to the  claim 1 , wherein the doping concentration of the conductive type dopant doped in the plurality of first barrier layers is increased having difference of one time to ten times per layer. 
     
     
         3 . The light emitting device according to the  claim 1 , wherein the plurality of first barrier layers and the at least one second barrier layer are spaced from each other and each of the first and second barrier layers combines with the quantum well layers. 
     
     
         4 . The light emitting device according to the  claim 1 , wherein the first conductive type semiconductor layer is doped with n-type dopant, the second conductive type semiconductor layer is doped with p-type dopant, and the conductive type dopant doped into the plurality of first barrier layers is n-type dopant. 
     
     
         5 . The light emitting device according to the  claim 2 , wherein the quantum well layers and the plurality of quantum barrier layers are laminated equal to or less than 30 times. 
     
     
         6 . The light emitting device according to the  claim 4 , wherein the plurality of second barrier layers are disposed to be closer to the first conductive type semiconductor layer than to the second conductive type semiconductor layer, and the at least one second barrier layer is disposed to be closer to the second conductive type semiconductor layer than to the first conductive type semiconductor layer. 
     
     
         7 . The light emitting device according to the  claim 1 , wherein the active layer generates light having at least two wavelength bands different from each other. 
     
     
         8 . The light emitting device according to the  claim 7 , wherein the plurality of quantum well layers and the plurality of barrier layers of the active layer are formed of semiconductor material having a compositional formula, In x Al y Ga 1−x−y N (0≦x≦1, 0≦y≦1, 0≦x+y≦1) and the indium contents contained in the plurality of quantum well layers are different from each other. 
     
     
         9 . The light emitting device according to the  claim 8 , wherein the active layer comprises a quantum well layer having indium (In) content of 10% to 30%. 
     
     
         10 . The light emitting device according to the  claim 8 , wherein the active layer emits light having a first wavelength band and light having a second wavelength band with main wavelength longer than that of the first wavelength band, and the indium content contained in the first region of the active layer emitting the light having the first wavelength band is less than that contained in the second region of the active layer emitting the light having the second wavelength band. 
     
     
         11 . The light emitting device according to the  claim 7 , wherein the plurality of quantum well layers and the plurality of barrier layers of the active layer have thicknesses different from each other. 
     
     
         12 . The light emitting device according to the  claim 11 , wherein the active layer emits light having a first wavelength band and light having a second wavelength range with main wavelength longer than that of the first wavelength band, and the thicknesses of a barrier layer and a quantum well layer in the first area of the active layer emitting the light having the first wavelength band are thinner than those of a barrier layer and a quantum well layer in the second region of the active layer emitting the light having the second wavelength band. 
     
     
         13 . The light emitting device according to the  claim 7 , wherein at least one of lights having at least two wavelength bands different from each other emitted from the active layer is a blue-based light of 430 nm to 470 nm. 
     
     
         14 . A light emitting device comprising:
 a first conductive type semiconductor layer;   an active layer including plurality of quantum well layers and plurality of barrier layers alternately laminated on the first conductive type semiconductor layer; and   a second conductive type semiconductor layer on the active layer,   wherein the plurality of barrier layers comprise plurality of first barrier layers doped with a conductive type dopant and at least one second barrier layer which is not doped with the conductive type dopant, and   the active layer comprises an region in which the plurality of first barrier layers and the at least one second barrier layer are alternately laminated.   
     
     
         15 . The light emitting device according to the  claim 14 , wherein the doping concentrations of the conductive type dopant doped into the plurality of first barrier layers are the same conductive type dopant concentration. 
     
     
         16 . The light emitting device according to the  claim 14 , wherein the doping concentrations of the conductive type dopant doped in the plurality of first barrier layers are different from each other. 
     
     
         17 . The light emitting device according to the  claim 14 , wherein the active layer generates light with at least two wavelength bands different from each other. 
     
     
         18 . The light emitting device according to the  claim 17 , wherein the plurality of quantum well layers and the plurality of barrier layers of the active layer are formed of semiconductor material having a compositional formula, In x Al y Ga 1−x−y N (0≦x≦1, 0≦y≦1, 0≦x+y≦1) and the indium contents contained in the plurality of quantum well layers are different from each other. 
     
     
         19 . The light emitting device according to the  claim 17 , wherein the plurality of quantum well layers and the plurality of barrier layers of the active layer have thicknesses different from each other. 
     
     
         20 . The light emitting device according to the  claim 14 , wherein the first conductive type semiconductor layer is doped with n-type dopant, the second conductive type semiconductor layer is doped with p-type dopant, and the conductive type dopant doped into the plurality of first barrier layers is n-type dopant.