Method of fabricating light emitting diode and light emitting diode manufactured thereby

1. A method of fabricating a light emitting diode, comprising:

forming a light emitting structure by sequentially stacking a first conductive type semiconductor layer, an active layer and a second conductive type semiconductor layer on a substrate;

forming a convex pattern on the light emitting structure;

transferring a nanosphere layer to an upper surface of the convex pattern; and

forming a stepped surface structure having a plurality of nanobumps arranged on the upper surface of the convex pattern by dry etching the nanosphere layer,

wherein transferring the nanosphere layer to the upper surface of the convex pattern comprises:

forming the nanosphere layer on a support substrate through nanosphere lithography;

attaching the nanosphere layer to the upper surface of the convex pattern using a thermal release tape, followed by thermal compression; and

removing the thermal release tape from the nanosphere layer.

2. The method of fabricating a light emitting diode according to claim 1 , wherein the convex pattern comprises a plurality of convex portions having one shape selected from among a semispherical shape, a conical shape or a poly-pyramidal shape.

3. The method of fabricating a light emitting diode according to claim 1 , wherein the step of forming the convex pattern on the light emitting structure is performed through photolithography.

4. The method of fabricating a light emitting diode according to claim 1 , wherein the step of forming the convex pattern on the light emitting structure comprises:

forming a material layer on a second support substrate;

forming the convex pattern on the material layer through photolithography; and

transferring the material layer having the convex pattern formed thereon to an upper surface of the light emitting structure.

5. The method of fabricating a light emitting diode according to claim 1 , wherein the step of forming the nanosphere layer on the support substrate through nanosphere lithography comprises:

depositing a solution, in which a plurality of nanosphere particles capable of self-assembling is dispersed, onto the support substrate; and

crystallizing the nanosphere particles into a colloid to form a nanosphere layer having a two-dimensional colloidal crystal structure on the support substrate.

6. The method of fabricating a light emitting diode according to claim 5 , wherein the nanosphere particles comprise at least one material selected from among silicon (Si), titanium (Ti), gold (Au), silver (Ag), platinum (Pt), iron (Fe), copper (Cu), aluminum (Al), nickel (Ni), and oxides, nitrides and sulfides thereof.

7. The method of fabricating a light emitting diode according to claim 5 , wherein the step of crystallizing the nanosphere particles into the colloid is performed by one method selected from among vacuum evaporation, electrostatic deposition, dip coating, Langmuir-Blodgett coating, electrophoretic deposition, and spin coating.

8. The method of fabricating a light emitting diode according to claim 1 , wherein the step of attaching the nanosphere layer to the convex pattern using the thermal release tape, followed by thermal compression, is performed at a temperature of 100° C. to 200° C. under a load of 0.1 MPa to 1 MPa.

9. The method of fabricating a light emitting diode according to claim 1 , wherein dry etching of the nanosphere layer is performed by inductively coupled plasma/reactive ion etching, or reactive ion etching using at least one etching gas selected from among Cl 2 , Ar, CH 4 , H 2 , HBr and BCl 3 .

10. The method of fabricating a light emitting diode according to claim 1 , further comprising: chemical coating the stepped surface structure to reduce surface energy thereof.

11. The method of fabricating a light emitting diode according to claim 10 , wherein the step of chemical coating the stepped surface structure to reduce surface energy thereof comprises depositing at least one material selected from among fluorinated acrylic copolymer, 1H,1H,2H,2H-heptadecafluorodecyl modified polyhedral oligomeric silsesquioxane (fluoroPOSS), PTFE amorphous fluoropolymer, fluorinated monoalkylphosphates, n-perfluoroeicosane, tridecafluoro-1,1,2,2-tetrahydrooctyltrichlorosilane, fluorinated 3,4-ethylenedioxypyrrole (EDOP) monomer, and semifluorinated silane ((tridecafluoro-1,1,2,2-tetrahydrooctyl)-1-trichlorosilane) on the stepped surface structure.

12. The method of fabricating a light emitting diode according to claim 10 , wherein the step of chemical coating the stepped surface structure to reduce surface energy thereof is performed by vacuum evaporation, spin coating, dip coating, spray coating, and molecular vapor deposition.

13. The method of fabricating a light emitting diode according to claim 1 , further comprising: before forming the convex pattern on the light emitting structure,

forming a reflective electrode layer on the light emitting structure;

partially etching the light emitting structure and the reflective electrode layer to expose a partial region of the first conductive type semiconductor layer;

forming a passivation layer on an upper surface of the reflective electrode layer and side surfaces of the light emitting structure and the reflective electrode layer exposed by etching;

forming a first electrode on the exposed partial region of the first conductive type semiconductor layer;

bonding a carrier substrate to an upper surface of the passivation layer via a bonding member;

separating the light emitting structure from the substrate; and

forming a second electrode on a partial region of the reflective electrode layer.

14. The method of fabricating a light emitting diode according to claim 1 , further comprising:

forming first and second electrodes on partial regions of the first conductive type semiconductor layer and the second conductive type semiconductor layer, respectively.