Method for manufacturing of a vertical light emitting device structure

Abstract

Disclosed are a vertical GaN based light-emitting device (LED) structure and the manufacturing method thereof. In the structure and the corresponding method, a substrate unit having a mask is used to form a multi-layer epitaxial structure and the substrate and the multi-layer epitaxial structure are separated at the mask. After the multi-layer epitaxial structure is extracted, a metal reflector may be disposed thereunder. Next, a conductive substrate is bonded to the metal reflector. Next, an upper surface of the multi-layer structure is disposed with a p-electrode and a bottom side of the conductive substrate with an n-electrode whereby an vertical LED structure is formed.

1 - 17 . (canceled)  
   
   
       18 . A vertical GaN based light-emitting device (LED) structure, comprising: 
 a multi-layer epitaxial structure, comprising: 
 an a-GaN based layer;  
 an MQW active layer formed over said n-GaN based layer; and  
 a contact layer made of a p-GaN based layer and formed over said MQW active layer;  
   a metal reflector used to reflect a light emitted from said MQW active layer;    a conductive substrate bonding with a bottom side of said metal reflector;    a p type metal electrode disposed over an upper surface of said multi-layer epitaxial structure; and    an n-type metal electrode disposed a bottom side of said conductive substrate.    
   
   
       19 . The structure as in  claim 18 , wherein said metal reflector comprises Ag/Al material, Ag or any metallic material, and has a reflectance of larger than 90%, wherein said Ag/Al material is a material having Ag at a bottom layer and Al on said Ag layer.  
   
   
       20 . The structure as in  claim 18 , wherein said conductive substrate comprises a Si-n, a GaAs-n, and InP-n and a GaP type substrates and may be doped with P, As and the Group-V elements.  
   
   
       21 . The structure as in  claim 18 , wherein said p-GaN based contact layer comprises a p + -GaN based semiconductor.  
   
   
       22 . The structure as in  claim 18 , wherein said p-GaN based layer comprises a p-GaN, a p-InGaN, a P-AlInGaN epitaxial layers.  
   
   
       23 . The structure as in  claim 18 , wherein said metal reflector may be formed by electroplating or sputtering.  
   
   
       24 . A vertical GaN based light-emitting device (LED) structure, comprising: 
 a multi-layer epitaxial structure, comprising: 
 an a-GaN based layer;  
 an MQW active layer formed over said n-GaN based layer;  
 a p-type distributed Bragg reflector (p-DBR); and  
 a contact layer made of a p-GaN based layer and formed over said MQW active layer;  
   a metal reflector used to reflect a light emitted from said MQW active layer, wherein said metal reflector and said p-DBR form a resonant cavity;    a conductive substrate bonding with a bottom side of said metal reflector;    a p type metal electrode disposed over an upper surface of said multi-layer epitaxial structure; and    an n-type metal electrode disposed a bottom side of said conductive substrate.    
   
   
       25 . The structure as in  claim 24 , wherein said metal reflector comprises Ag/Al material, Ag or any metallic material, and has a reflectance of larger than 90%, wherein said Ag/Al material is a material having Ag at a bottom layer and Al on said Ag layer.  
   
   
       26 . The structure as in  claim 24 , wherein said conductive substrate comprises a Si-n, a GaAs-n, an InP-n and a GaP type substrates and may be doped with P, As and the Group-V elements.  
   
   
       27 . The structure as in  claim 24 , wherein said p-GaN based contact layer comprises a p + -GaN based semiconductor.  
   
   
       28 . The structure as in  claim 24 , wherein said p-GaN based layer comprises a p-GaN, a p-InGaN, a p-AlInGaN epitaxial layers.  
   
   
       29 . The structure as in  claim 24 , wherein said metal reflector may be formed by electroplating or sputtering.  
   
   
       30 . The structure as in  claim 24 , wherein said p-DBR has a reflectance of 50-80%.  
   
   
       31 . A vertical GaN based light-emitting device (LED) structure, comprising: 
 a multi-layer epitaxial structure, comprising: 
 an a-GaN based layer;  
 a second multi-quantum well (MQW) active layer formed over said n-GaN based layer;  
 a second n-GaN based layer;  
 a first MQW layer;  
 a p-type distributed Bragg reflector (p-DBR); and  
 a contact layer made of a p-GaN based layer and formed over said p-DBR;  
   a metal reflector used to reflect a light emitted from said MQW active layer, wherein said metal reflector and said p-DBR form a resonant cavity;    a conductive substrate bonding with a bottom side of said metal reflector;    a p type metal electrode disposed over an upper surface of said multi-layer epitaxial structure; and    an n-type metal electrode disposed a bottom side of said conductive substrate;    wherein said second MQW layer comprises a material so that said second  20  MQW layer may emits a second light having a second wavelength upon excited and said first MQW layer comprises a material so that said first MQW layer may emits a first light having a first wavelength upon an applied electric power, wherein said second wavelength is longer than said first wavelength.    
   
   
       32 . The structure of  claim 31 , wherein said metal reflector comprises Ag/Al material, Ag or any metallic material, and has a reflectance or larger than 90%, wherein said Ag/Al material is a material having Ag at a bottom layer and Al on said Ag layer.  
   
   
       33 . The structure of  claim 31 , wherein said conductive substrate comprises a Si-n, a GaAs-n, an InP-n and a GaP type substrates and may be doped with P, As and the Group-V elements.  
   
   
       34 . The structure of  claim 31 , wherein said p-GaN based contact layer comprises a p + -GaN based semiconductor.  
   
   
       35 . The structure of  claim 31 , wherein said p-GaN based layer comprises a p-GaN, a p-InGaN, a p-AlInGaN epitaxial layers.  
   
   
       36 . The structure of  claim 31 , wherein said p-DBR has reflectance of 50-80%.  
   
   
       37 . The structure of  claim 31 , wherein said metal reflector may at least be formed by electroplating or sputtering.  
   
   
       38 - 39 . (canceled)