Semiconductor light emitting device with transparent electrode having holes

Abstract

A semiconductor light emitting device and a fabrication method thereof includes: providing a substrate; forming an n-type semiconductor layer, a light emitting layer, a p-type semiconductor layer on the substrate; forming a first transparent electrode having holes per a certain region on the p-type semiconductor layer; and forming a first pad on the first transparent electrode.A method of fabricating a semiconductor light emitting device, and which includes forming a light emitting layer on the first type semiconductor layer; forming a second type semiconductor layer on the light emitting layer; forming a first transparent electrode on the second type semiconductor layer, the first transparent electrode having holes per a certain region to thereby expose the second type semiconductor layer; forming a second transparent electrode on the first transparent electrode; forming a first pad on the second transparent electrode; and forming a second pad over the first type semiconductor layer. Further, the first transparent electrode is in the shape of columns with gaps therebetween on the second type semiconductor layer, and the second transparent electrode completely covers the first transparent electrode and fills the gaps of the first transparent electrode.

What is claimed is: 
     
       1. A fabrication method of a semiconductor light emitting device comprising:
 providing a substrate;   forming an n-type semiconductor layer, a light emitting layer, and a p-type semiconductor layer on the substrate;   forming a first transparent electrode on the p-type semiconductor layer, said first transparent electrode having holes per a certain region to thereby expose the p-type semiconductor layer;   forming a first pad on the first transparent electrode; and   forming a second transparent electrode on the first transparent electrode.   
     
     
       2. The method of  claim 1 , wherein the providing the substrate is performed by providing a sapphire substrate. 
     
     
       3. The method of  claim 2 , further comprising:
 performing a mesa-etching from the p-type semiconductor layer to the n-type semiconductor layer partially in a vertical direction, and thereby exposing a part of the n-type semiconductor layer; and   forming a second pad on the exposed n-type semiconductor layer.   
     
     
       4. The method of  claim 1 , wherein the providing the substrate is performed by providing a silicon carbide substrate. 
     
     
       5. The method of  claim 4  further comprising forming the second pad on a rear surface of the silicon carbide substrate. 
     
     
       6. The method of  claim 1 , wherein the forming a first transparent electrode is performed by selecting one from a group composed of Ni, Au, Pd, Pt, Ir, Zn, and Mg or by forming a mixture of at least two therebetween. 
     
     
       7. The method of  claim 1 , wherein the forming the first transparent electrode comprises:
 forming a first metal layer by depositing a metal group that at least one metal oxide generating metal and at least one current spreading metal are mixed on the p-type semiconductor layer; and   annealing the first metal layer.   
     
     
       8. The method of  claim 7 , wherein the metal oxide generating metal is one selected from a group composed of Ni, Pd, Pt, Ir, Zn, and Mg, or a mixture of at least two therebetween. 
     
     
       9. The method of  claim 7 , wherein the current spreading metal is Au. 
     
     
       10. The method of  claim 1 , wherein the holes comprise empty spaces between pillars of the first transparent electrode. 
     
     
       11. The method of  claim 1 , further comprising forming a second transparent electrode on the first transparent electrode. 
     
     
       12. The method of  claim 1 , wherein the second transparent electrode is formed of one selected from a group composed of ITO, IZO, ZnO, AZO, CdO and MgO. 
     
     
       13. A fabrication method of a semiconductor light emitting device comprising:
 providing a substrate;   forming an n-type semiconductor layer, a light emitting layer, a p-type semiconductor layer on the substrate;   forming a first transparent electrode having holes per a certain region on the p-type semiconductor layer;   forming a first pad on the first transparent electrode; and   forming a second transparent electrode on the first transparent electrode,   wherein the forming a first transparent electrode comprises:   forming a first metal layer by depositing a metal group that at least one metal oxide generating metal and at least one current spreading metal are mixed on the p-type semiconductor layer; and   annealing the first metal layer.   
     
     
       14. The method of  claim 13 , wherein the second transparent electrode is formed of one selected from a group composed of ITO, IZO, ZnO, AZO, CdO, and MgO. 
     
     
       15. A fabrication method of a semiconductor light emitting device comprising:
 providing a substrate;   forming an n-type semiconductor layer, a light emitting layer, a p-type semiconductor layer on the substrate;   forming a first transparent electrode having holes per a certain region on the p-type semiconductor layer; and   forming a second transparent electrode on the first transparent electrode,   wherein the second transparent electrode comprises a metal oxide.   
     
     
       16. The method of  claim 15 , wherein the second transparent electrode is formed of one selected from a group composed of ITO, IZO, ZnO, AZO, CdO, and MgO. 
     
     
       17. A fabrication method of a semiconductor light emitting device comprising:
 providing a substrate;   forming an n-type semiconductor layer, a light emitting layer, and a p-type semiconductor layer on the substrate;   depositing a metal group that at least one metal oxide generating metal and at least one current spreading metal are mixed on the p-type semiconductor layer, and thereby forming a first transparent electrode;   forming a first pad on the p-type semiconductor layer;   forming holes that expose the p-type semiconductor layer per a certain region on the first transparent electrode; and   forming a second transparent electrode on the first transparent electrode.   
     
     
       18. The method of  claim 17 , wherein the providing the substrate is performed by providing a sapphire substrate. 
     
     
       19. The method of  claim 18 , further comprising:
 performing a mesa-etching from the p-type semiconductor layer to the n-type semiconductor layer partially in a vertical direction, and thereby exposing a part of the n-type semiconductor layer; and   forming a second pad on the exposed n-type semiconductor layer.   
     
     
       20. The method of  claim 17 , wherein the providing the substrate is performed by providing a silicon carbide substrate. 
     
     
       21. The method of  claim 20 , further comprising forming a second pad on a rear surface of the silicon carbide substrate. 
     
     
       22. The method of  claim 17 , wherein the metal oxide generating metal is one selected from a group composed of Ni, Pd, Pt, Ir, Zn, and Mg or a mixture of at least two therebetween. 
     
     
       23. The method of  claim 17 , wherein the current spreading metal is Au. 
     
     
       24. The method of  claim 17 , wherein the holes comprise empty spaces between pillars of the first transparent electrode. 
     
     
       25. The method of  claim 17 , further comprising forming a second transparent electrode on the first transparent electrode. 
     
     
       26. The method of  claim 17 , wherein the second transparent electrode is one selected from a group composed of ITO, IZO, ZnO, AZO, CdO, and MgO. 
     
     
       27. A fabrication method of a semiconductor light emitting device comprising:
 providing a substrate;   forming an n-type semiconductor layer, a light emitting layer, a p-type semiconductor layer on the substrate;   depositing a metal group that at least one metal oxide generating metal and at least one current spreading metal are mixed on the p-type semiconductor layer, and thereby forming a first transparent electrode;   forming a first pad on the p-type semiconductor layer; and   forming a second transparent electrode on the first transparent electrode.   
     
     
       28. The method of  claim 27 , wherein the second transparent electrode is one selected from a group composed of ITO, IZO, ZnO, AZO, CdO, and MgO. 
     
     
       29. A method of fabricating a semiconductor light emitting device, the method comprising:
 providing a substrate;   forming a first type semiconductor layer on the substrate;   forming a light emitting layer on the first type semiconductor layer;   forming a second type semiconductor layer on the light emitting layer;   forming a first transparent electrode on the second type semiconductor layer, the first transparent electrode having holes per a certain region to thereby expose the second type semiconductor layer;   forming a second transparent electrode on the first transparent electrode;   forming a first pad on the second transparent electrode; and   forming a second pad over the first type semiconductor layer,   wherein the first transparent electrode is in the shape of columns with gaps therebetween on the second type semiconductor layer,   wherein the first type semiconductor layer is an n-type semiconductor layer, and the second type semiconductor layer is a p-type semiconductor layer,   wherein the second transparent electrode completely covers the first transparent electrode and fills the gaps of the first transparent electrode, and   wherein the first transparent electrode includes at least one of a metal and a metal oxide.    
     
     
       30. The method of claim 29, wherein the substrate is a sapphire substrate or a silicon carbide substrate.  
     
     
       31. The method of claim 29, wherein a thickness of the first transparent electrode is approximately 1 nm-100 nm.  
     
     
       32. The method of claim 29, wherein a thickness the first type semiconductor layer is 1 μm-500 μm and a thickness of the second type semiconductor layer is 0.1 μm-100 μm.