High brightness light-emitting device and manufacturing process of the light-emitting device

Abstract

A light-emitting device comprises a multi-layer structure including one or more active layer configured to irradiate light in response to the application of an electric signal, a transparent passivation layer laid over an outmost surface of the multi-layer stack, a reflector layer laid over the passivation layer, and a plurality of electrode pads coupled with the multi-layer structure. In a manufacture process of the light-emitting device, the reflector layer and the passivation layer are patterned to form at least one opening exposing an area of the multi-layer structure. One electrode pad is formed through the opening of the reflector layer and the passivation layer to connect with the multi-layer structure

1 . A light-emitting device comprising: 
 a multi-layer structure including one or more active layer configured to irradiate light in response to the application of an electric signal;    a transparent passivation layer laid over an outmost surface of the multi-layer structure;    a reflector layer laid over the passivation layer; and    a plurality of electrode pads coupled with the multi-layer structure.    
   
   
       2 . The light-emitting device according to  claim 1 , wherein the electrode pads include at least one electrode pad extending through the reflector layer and the transparent passivation layer to contact with the multi-layer structure.  
   
   
       3 . The light-emitting device according to  claim 1 , further comprising a second passivation layer covering the reflector layer.  
   
   
       4 . The light-emitting device according to  claim 1 , wherein the reflector layer is made of a material composition including Pd, Rh, Ag, Al, Ni, Pt, Ti, Cu, Au, Cr, In, Sn, Ir, or the like.  
   
   
       5 . The light-emitting device according to  claim 1 , wherein the reflector layer has a reflectivity greater than about 65%.  
   
   
       6 . The light-emitting device according to  claim 1 , wherein the transparent passivation layer is made of a material composition including SiO x , Si x N x , benzocyclobutene, spin-on-glass, epoxy-based negative resists, AlN, SiC or the like.  
   
   
       7 . The light-emitting device according to  claim 1 , wherein the light-emitting device is further mounted on a substrate provided with contact pads.  
   
   
       8 . The light-emitting device according to  claim 7 , wherein the electrode pads of the light-emitting device are connected to the contact pads of the substrate via conductive bumps.  
   
   
       9 . The light-emitting device according to  claim 1 , wherein a first area of the multi-layer structure encompasses the stack of a substrate, a first cladding layer, and a first ohmic contact layer, and a second area of the multi-layer structure encompasses the stack of the substrate, the first cladding layer, the active layer and a second ohmic contact layer.  
   
   
       10 . The light-emitting device according to  claim 9 , wherein the first cladding layer includes an n-type GaN layer.  
   
   
       11 . The light-emitting device according to  claim 9 , wherein the second cladding layer includes a p-type GaN layer.  
   
   
       12 . The light-emitting device according to  claim 9 , wherein the first ohmic contact layer includes Ti/Al, Ti/Al/Ti/Au, Ti/Al/Pt/Au, Ti/Al/Ni/Au, Ti/Al/Pd/Au, Ti/Al/Cr/Au, Ti/Al/Co/Au, Cr/Al/Cr/Au, Cr/Al/Pt/Au, Cr/Al/Pd/Au, Cr/Al/Ti/Au, Cr/Al/Co/Au, Cr/Al/Ni/Au, Pd/Al/Ti/Au, Pd/Al/Pt/Au, Pd/Al/Ni/Au, Pd/Al/Pd/Au, Pd/Al/Cr/Au, Pd/Al/Co/Au, Nd/Al/Pt/Au, Nd/Al/Ti/Au, Nd/Al/Ni/Au, Nd/Al/Cr/Au, Nd/Al/Co/A, Hf/Al/Ti/Au, Hf/Al/Pt/Au, Hf/Al/Ni/Au, Hf/Al/Pd/Au, Hf/Al/Cr/Au, Hf/Al/Co/Au, Zr/Al/Ti/Au, Zr/Al/Pt/Au, Zr/Al/Ni/Au, Zr/Al/Pd/Au, Zr/Al/Cr/Au, Zr/Al/Co/Au, TiNx/Ti/Au, TiN x /Pt/Au, TiN x /Ni/Au, TiN x /Pd/Au, TiN x /Cr/Au, TiN x /Co/Au TiWN x /Ti/Au, TiWN x /Pt/Au, TiWN x /Ni/Au, TiWN x /Pd/Au, TiWN x /Cr/Au, TiWN x /Co/Au, NiAl/Pt/Au, NiAl/Cr/Au, NiAl/Ni/Au, NiAl/Ti/Au, Ti/NiAl/Pt/Au, Ti/NiAL/Ti/Au, Ti/NiAl/Ni/Au, Ti/NiAl/Cr/Au or the like.  
   
   
       13 . The light-emitting device according to  claim 9 , wherein the second contact layer is made of a conductive metallic alloy including Ni/Au, Ni/Pt, Ni/Pd, Ni/Co, Pd/Au, Pt/Au, Ti/Au, Cr/Au, Sn/Au, Ta/Au, TiN, TiWN x , WSi x , or the like.  
   
   
       14 . The light-emitting device according to  claim 9 , wherein the second ohmic contact layer is made of a transparent conductive oxide including indium tin oxide, cadmium tin oxide, ZnO:Al, ZnGa 2 O 4 , SnO 2 :Sb, Ga 2 O 3 :Sn, AgInO 2 :Sn, In 2 O 3 :Zn, NiO, MnO, FeO, Fe 2 O 3 , CoO, CrO, Cr 2 O 3 , CrO 2 , CuO, SnO, GaO, RuO 2 , Ag 2 O, CuAlO 2 , SrCu 2 O 2 , LaMnO 3 , PdO or the like.