Top-emitting light emitting diodes and methods of manufacturing thereof
View Patent ↗Provided are a top-emitting nitride based light emitting device having an n-type clad layer, an active layer and a p-type clad layer sequentially stacked thereon, comprising an interface modification layer formed on the p-type clad layer and a transparent conductive thin film layer made up of a transparent conductive material formed on the interface modification layer; and a process for preparing the same. In accordance with the top-emitting nitride-based light emitting device of the present invention and a process for preparing the same, there are provided advantages such as improved ohmic contact with the p-type clad layer, leading to increased wire bonding efficiency and yield upon packaging the light emitting device, capability to improve luminous efficiency and life span of the device due to low specific contact resistance and excellent current-voltage properties.
1. A top-emitting nitride-based light emitting device, comprising:
an active layer between an n-type clad layer and a p-type clad layer:
an interface modification layer formed on the p-type clad layer; and
a transparent conductive thin film layer made up of a transparent conductive material formed on the interface modification layer,
wherein the interface modification layer is formed of an alloy to which additional elements are added while containing indium as a main component, or a solid solution thereof, and
wherein the additional elements added to indium for the interface modification layer include at least one selected from tin (Sn), zinc (Zn), gallium (Ga), cadmium (Cd), magnesium (Mg), beryllium (Be), silver (Ag), molybdenum (Mo), vanadium (V), copper (Cu), iridium (Ir), rhodium (Rh), ruthenium (Ru), tungsten (W), cobalt (Co), nickel (Ni), manganese (Mn), palladium (Pd), platinum (Pt) and lanthanum (La).
2. The light emitting device according to claim 1 , wherein the ratio of the additional element added relative to indium is within the range of 0.001 to 50 wt%.
3. The light emitting device according to claim 1 , wherein the interface modification layer is formed of a p-type transparent conductive oxide.
4. The light emitting device according to claim 1 , wherein the interface modification layer contains a binary or ternary oxide formed of at least one element selected from Group II elements including magnesium (Mg), zinc (Zn), and beryllium (Be).
5. The light emitting device according to claim 1 , wherein the interface modification layer contains any one oxide selected from Ag 2 O, CuAlO 2 , SrCu 2 O 2 , LaMnO 3 , LaNiO 3 , and In x O 1-x .
6. The light emitting device according to claim 4 , wherein the interface modification layer is formed by further adding a p-type dopant to the oxide.
7. A top-emitting nitride-based light emitting device, comprising:
an active layer between an n-type clad layer and a p-type clad layer;
an interface modification layer formed on the p-type clad layer: and
a transparent conductive thin film layer made up of a transparent conductive material formed on the interface modification layer,
wherein the interface modification layer is formed of an alloy to which an additional element is added while containing tin as a main component, or a solid solution thereof, and
wherein the additional element added to tin for the interface modification layer includes at least one selected from indium (In), zinc (Zn), gallium (Ga), cadmium (Cd), magnesium (Mg), beryllium (Be), silver (Ag), molybdenum (Mo), vanadium (V), copper (Cu), iridium (Ir), rhodium (Rh), ruthenium (Ru), tungsten (W), cobalt (Co), nickel (Ni), manganese (Mn), palladium (Pd), platinum (Pt) and lanthanum (La).
8. The light emitting device according to claim 7 , wherein the ratio of the additional element added relative to tin is within the range of 0.001 to 50 wt%.
9. The light emitting device according to claim 7 , wherein the interface modification layer is formed of a p-type transparent conductive oxide.
10. The light emitting device according to claim 7 , wherein the interface modification layer contains a binary or ternary oxide formed of at least one element selected from Group II elements including magnesium (Mg), zinc (Zn), and beryllium (Be).
11. The light emitting device according to claim 7 , wherein the interface modification layer contains any one oxide selected from Ag 2 O, CuAlO 2 , SrCu 2 O 2 , LaMnO 3 , LaNiO 3 , and In x O 1-x .