Light-emitting gallium nitride-based III-V group compound semiconductor device and manufacturing method thereof

Abstract

A light-emitting gallium nitride-based III-V group compound semiconductor device and a manufacturing method thereof are disclosed. The light emitting device includes a substrate, a n-type semiconductor layer over the substrate, an active layer over the n-type semiconductor layer, a p-type semiconductor layer over the active layer, a conductive layer over the p-type semiconductor layer, a first electrode disposed on the conductive layer and a second electrode arranged on exposed part of the n-type semiconductor layer. A resistant reflective layer or a contact window is disposed on the p-type semiconductor layer, corresponding to the first electrode so that current passes beside the resistant reflective layer or by the contact window to the active layer for generating light. When the light is transmitted to the conductive layer for being emitted, it is not absorbed or shielded by the first electrode. Thus the current is distributed efficiently over the conductive layer. Therefore, both LED brightness and efficiency are improved. Moreover, adhesion between the conductive layer and the p-type semiconductor layer is improved so that metal peel-off problem during manufacturing processes can be improved.

1 . A manufacturing method of light-emitting gallium nitride-based III-V group compound semiconductor devices comprising the steps of:
 providing a substrate;   forming a n-type semiconductor layer over the substrate;   forming an active layer over the n-type semiconductor layer;   forming a p-type semiconductor layer over the active layer;   performing an etching process to expose part of the n-type semiconductor layer;   forming a resistant and reflective layer over the p-type semiconductor layer;   forming a conductive layer over the resistant and reflective layer and the p-type semiconductor layer;   forming a first electrode that is corresponding to the resistant and reflective layer over the conductive layer;   forming a second electrode over exposed part of the n-type semiconductor layer.   
   
   
       2 . The method as claimed in  claim 1 , wherein the resistant and reflective layer is a dielectric reflective layer, a metal reflective layer or combinations of them. 
   
   
       3 . The method as claimed in  claim 2 , wherein the dielectric reflective layer is made from silicon dioxide, silicon monoxide, silicon tetranitride, nitride, amorphous semiconductor, non-crystal semiconductor, zinc oxide, nickel oxide, titanium dioxide, oxide or combinations of them. 
   
   
       4 . The method as claimed in  claim 2 , wherein the dielectric reflective layer is made from combinations of at least two materials with different refractive index. 
   
   
       5 . The method as claimed in  claim 2 , wherein the metal reflective layer comprising a plurality of metal particles. 
   
   
       6 . A manufacturing method of light-emitting gallium nitride-based III-V group compound semiconductor devices comprising the steps of:
 providing a substrate;   forming a n-type semiconductor layer over the substrate;   forming an active layer over the n-type semiconductor layer;   forming a p-type semiconductor layer over the active layer;   forming a contact window on the p-type semiconductor layer;   performing an etching process to expose part of the n-type semiconductor layer;   forming a conductive layer over the contact window and the p-type semiconductor layer;   forming a first electrode over the conductive layer and corresponding to the contact window; and   forming a second electrode over exposed part of the n-type semiconductor layer.   
   
   
       7 . The method as claimed in  claim 6 , wherein the contact window is formed by an etching process or an ion implantation process. 
   
   
       8 . The method as claimed in  claim 6 , wherein a resistant and reflective layer is arranged over the contact window. 
   
   
       9 . The method as claimed in  claim 8 , wherein the resistant and reflective layer is a dielectric reflective layer, a metal reflective layer or combinations of them. 
   
   
       10 . The method as claimed in  claim 9 , wherein the dielectric reflective layer is made from silicon dioxide, silicon monoxide, silicon tetranitride, nitride, amorphous semiconductor, non-crystal semiconductor, zinc oxide, nickel oxide, titanium dioxide, oxide or combinations of them. 
   
   
       11 . The method as claimed in  claim 9 , wherein the dielectric reflective layer is made from combinations of at least two materials with different refractive index. 
   
   
       12 . The method as claimed in  claim 9 , wherein the metal reflective layer comprising a plurality of metal particles.