Gallium-nitride based light-emitting diode structure with high reverse withstanding voltage and anti-ESD capability

A GaN-based LED structure, comprising:

• a substrate made of a material selected from the group consisting of sapphire,
• 6H—SiC, 4H—SiC, Si, ZnO, GaAs, MgAl2O4, and an oxide monocrystalline having a lattice constant compatible with that of nitride semiconductors;
• a buffer layer made of AlaGabIn1-a-bN (0≦a,b<1, a+b≦1) having a specific composition located on top of an upper side of said substrate;
• an n-type contact layer made of a GaN-based material located on top of said buffer layer;
• an active layer made of InGaN located on top of a part of said n-type contact layer's upper surface;
• a negative electrode located on top of another part of said n-type contact layer's upper surface not covered by said active layer;
• a p-type cladding layer made of a p-type GaN-based material located on top of said active layer;
• a p-type contact layer made of p-type GaN located on top of said p-type cladding layer;
• an anti-ESD thin layer made of a material selected from the group consisting of undoped InGaN, undoped AlInGaN having a band gap less than 3.4 eV, and a superlattice structure comprising undoped InGaN and undoped AlInGaN having a band gap less than 3.4 eV;
• a transparent conductive layer selected from the group consisting of a metallic conductive layer and a transparent oxide layer, located on top of a part of said anti-ESD thin layer's upper surface, wherein said metallic conductive layer is made of a material selected from the group consisting of Ni/Au alloy, Ni/Pt alloy, Ni/Pd alloy, Pd/Au alloy, Pt/Au alloy, Cr/Au alloy, Ni/Au/Be alloy, Ni/Cr/Au alloy, Ni/Pt/Au alloy, and Ni/Pd/Au alloy, and said transparent oxide layer is made of a material selected from the group consisting of IFO, CTO, ZnO:Al, ZnGa2O4, SnO2:Sb, Ga2O3:Sn, AglnO2:Sn, In2O3:Zn, CuAlO2, LaCuOS, NiO, CuGaO2, and SrCu2O2;
• and
• a positive electrode located on top of another part of said anti-ESD thin layer's upper surface not covered by said transparent conductive layer, made of a material selected from the group consisting of Ni/Au alloy, Ni/Pt alloy, Ni/Pd alloy, Ni/Co alloy, Pd/Au alloy, Pt/Au alloy, Ti/Au alloy, Cr/Au alloy, Sn/Au alloy, Ta/Au alloy, TiN, TiWNx (x≧0), and WSiy (y≧0).