Light emitting diode and method of manufacturing the same

Abstract

A light emitting diode having high light extraction efficiency and a method of manufacturing the same are provided. The LED includes a semiconductor multiple layer including an active layer; a transparent electrode layer formed on the semiconductor multiple layer; and refraction field unit embedded in the transparent electrode layer and formed of a material having a different refractive index than the transparent electrode layer. The method of manufacturing the LED includes: crystallizing and growing a semiconductor multiple layer having an active layer on a substrate; evaporating a first transparent electrode layer onto the semiconductor multiple layer; forming a plurality of grooves in the first transparent electrode layer by patterning and etching the first transparent electrode layer; and evaporating a second transparent electrode layer onto the first transparent electrode layer at an angle to the grooves to form cavities filled with air between the first transparent electrode layer and the second transparent electrode layer.

1 . A light emitting diode (LED) comprising:
 a semiconductor multiple layer comprising an active layer;   a transparent electrode layer formed on the semiconductor multiple layer; and   a refraction field unit embedded in the transparent electrode layer and formed of a material having a different refractive index than the transparent electrode layer.   
   
   
       2 . The LED of  claim 1 , wherein the refraction field unit is formed of a material having a lower refractive index than the transparent electrode layer. 
   
   
       3 . The LED of  claim 2 , wherein the transparent electrode layer is formed of a material selected from the group consisting of ITO, ZnO, and SnO 2 , and the refraction field unit is formed of a material selected from the group consisting of SiO 2 , porous SiO 2 , KDP, NH 4 H 2 PO 4 , CaCO 3 , BaB 2 O 4 , NaF, and Al 2 O 3 . 
   
   
       4 . The LED of  claim 1 , wherein the refraction field unit is formed of a material having a higher refractive index than the transparent electrode layer. 
   
   
       5 . The LED of  claim 4 , wherein the transparent electrode layer is formed of a material selected from the group consisting of ITO, ZnO, and SnO 2 , and the refraction field unit is formed of a material selected from the group consisting of SiC, LiNbO 3 , LilO 3 , PbMoO 4 , Nb 2 O 5 , TiO 2 , and ZrO 2 . 
   
   
       6 . The LED of  claim 1 , wherein the refraction field unit comprises a plurality of cavities filled with air. 
   
   
       7 . The LED of  claim 1 , wherein the refraction field unit comprises a plurality of refraction regions arranged at predetermined intervals in the transparent electrode layer. 
   
   
       8 . The LED of  claim 7 , wherein the interval of the refraction regions is at least 0.5 times the wavelength of light generated by the active layer. 
   
   
       9 . A method of manufacturing an LED comprising:
 forming a semiconductor multiple layer having an active layer on a substrate;   evaporating a first transparent electrode layer onto the semiconductor multiple layer;   forming a refraction layer on the first transparent electrode layer by evaporating a material having a different refractive index than the first transparent electrode layer onto the first transparent electrode layer;   forming refraction field unit by patterning and etching the refraction layer; and   embedding the refraction field unit by evaporating a second transparent electrode layer on the refraction field unit and the first transparent electrode layer.   
   
   
       10 . The LED of  claim 9 , wherein the refraction field unit comprises a plurality of refraction regions arranged at predetermined intervals in the transparent electrode layer. 
   
   
       11 . The LED of  claim 10 , wherein the interval of the refraction regions is at least 0.5 times the wavelength of light generated by the active layer. 
   
   
       12 . A method of manufacturing the LED of  claim 6 , the method comprising:
 forming a semiconductor multiple layer having an active layer on a substrate;   evaporating a first transparent electrode layer onto the semiconductor multiple layer;   forming a plurality of grooves in the first transparent electrode layer by patterning and etching the first transparent electrode layer; and   evaporating a second transparent electrode layer onto the first transparent electrode layer at an angle to the grooves to form refraction field unit formed of cavities filled with air between the first transparent electrode layer and the second transparent electrode layer.