Nitride semiconductor structure

Abstract

A nitride semiconductor structure and a semiconductor light emitting device including the same are revealed. The nitride semiconductor structure includes a multiple quantum well structure formed by a plurality of well layers and barrier layers stacked alternately. One well layer is disposed between every two barrier layers. The barrier layer is made of A x In y Ga 1−x−y N (0<x<1, 0<y<1, 0<x+y<1) while the well layer is made of In z Ga 1−z N (0<z<1). Thereby quaternary composition is adjusted for lattice match between the barrier layers and the well layers. Thus crystal defect caused by lattice mismatch is improved.

What is claimed is: 
     
         1 . A nitride semiconductor structure comprising:
 a first type doped semiconductor layer;   a second type doped semiconductor layer;   a light emitting layer disposed between the second type doped semiconductor layer and the first type doped semiconductor layer, the light emitting layer comprising a multiple quantum well (MQW) structure, wherein the MQW structure comprises a plurality of barrier layers and a plurality of well layers stacked alternately;   an InGaN based second type hole supply layer disposed between the second type doped semiconductor layer and the light emitting layer; and   an AlGaN based second type carrier blocking layer disposed between the second type doped semiconductor layer and the light emitting layer,   wherein the InGaN based second type hole supply layer is doped with a second type dopant at a concentration larger than 10 18  cm −3  and carbon at a concentration between 10 17  cm −3  and 10 20  cm −3 .   
     
     
         2 . The nitride semiconductor structure as claimed in  claim 1 , wherein a material of each of the barrier layers of the MQW structure is doped with a first type dopant at a concentration ranging from 10 16  cm −3  to 10 18  cm −3 . 
     
     
         3 . The nitride semiconductor structure as claimed in  claim 1 , wherein a band gap of the InGaN based second type hole supply layer is larger than a band gap of each of the well layers of the MQW structure. 
     
     
         4 . The nitride semiconductor structure as claimed in  claim 1 , wherein the second type dopant in the InGaN based second type hole supply layer is magnesium. 
     
     
         5 . The nitride semiconductor structure as claimed in  claim 1 , further comprising:
 an AlGaN based first type carrier blocking layer, disposed between the first type doped semiconductor layer and the light emitting layer.   
     
     
         6 . A nitride semiconductor structure comprising:
 a first type doped semiconductor layer;   a second type doped semiconductor layer;   a light emitting layer disposed between the second type doped semiconductor layer and the first type doped semiconductor layer, the light emitting layer comprising a multiple quantum well (MQW) structure, wherein the MQW structure comprises a plurality of barrier layers and a plurality of well layers stacked alternately;   an InGaN based second type hole supply layer disposed between the second type doped semiconductor layer and the light emitting layer;   an AlGaN based first type carrier blocking layer disposed between the first type doped semiconductor layer and the light emitting layer; and   an AlGaN based second type carrier blocking layer disposed between the second type doped semiconductor layer and the InGaN based second type hole supply layer,   wherein the InGaN based second type hole supply layer is doped with a second type dopant at a concentration larger than 10 18  cm −3  and carbon at a concentration between 10 17  cm −3  and 10 20  cm −3 .   
     
     
         7 . The nitride semiconductor structure as claimed in  claim 6 , wherein a material of each of the barrier layers of the MQW structure is doped with a first type dopant at a concentration is ranging from 10 16  cm −3  to 10 18  cm −3 . 
     
     
         8 . The nitride semiconductor structure as claimed in  claim 6 , wherein a band gap of the InGaN based second type hole supply layer is larger than a band gap of each of the well layers of the MQW structure. 
     
     
         9 . The nitride semiconductor structure as claimed in  claim 6 , wherein the second type dopant in the InGaN based second type hole supply layer is magnesium.