Nano-structured light-emitting devices
A nano-structured light-emitting device includes a plurality of light-emitting nanostructures each having a resistant layer disposed thereon. The device includes a first semiconductor layer of a first conductivity type, and a plurality of nanostructures disposed on the first semiconductor layer. Each nanostructure includes a nanocore, and an active layer and a second semiconductor layer of a second conductivity type that enclose surfaces of the nanocores. An electrode layer encloses and covers the plurality of nanostructures A plurality of resistant layers are disposed on the electrode layer and each corresponds to a respective nanostructure of the plurality of nanostructures.
1. A nano-structured light-emitting device comprising:
a first semiconductor layer of a first conductivity type;
a plurality of nanostructures disposed on the first semiconductor layer and each comprising a nanocore, and an active layer and a second semiconductor layer of a second conductivity type that enclose surfaces of the nanocore;
an electrode layer enclosing and covering the plurality of nanostructures, the electrode layer having a first surface facing the plurality of nanostructures; and
a plurality of resistant layers disposed on a second surface of the electrode layer opposite to the first surface and each corresponding to a respective nanostructure of the plurality of nanostructures.
2. The nano-structured light-emitting device of claim 1 , wherein the resistant layers are disposed to cover portions of the nanostructures and are spaced apart from one another so as not to contact each other.
3. The nano-structured light-emitting device of claim 1 , wherein the resistant layers each have a resistance value that is greater than or equal to resistance values of the nanostructures.
4. The nano-structured light-emitting device of claim 1 , further comprising:
an insulating layer disposed between adjacent nanostructures to electrically insulate the resistant layer of one nanostructure from the resistant layers of other nanostructures.
5. The nano-structured light-emitting device of claim 4 , wherein the resistant layers are disposed only on portions of electrode layers that do not contact the insulating layer.
6. The nano-structured light-emitting device of claim 1 , further comprising:
a conductive layer disposed on the plurality of resistant layers to connect the plurality of nanostructures to one another in parallel.
7. The nano-structured light-emitting device of claim 1 , wherein the nanostructures are electrically interconnected into a plurality of groups corresponding to a plurality of pixels,
wherein the pixels are separated from one another by trenches.
8. The nano-structured light-emitting device of claim 7 , wherein an insulating material is disposed in the trenches.
9. The nano-structured light-emitting device of claim 1 , further comprising:
a mask layer disposed on an upper surface of the first semiconductor layer and comprising through-holes,
wherein the nanocores protrude from the through-holes.
10. The nano-structured light-emitting device of claim 6 , further comprising:
a first electrode pad electrically connected to the first semiconductor layer; and
a second electrode pad electrically connected to the conductive layer.
11. The nano-structured light-emitting device of claim 1 , further comprising:
a substrate disposed underneath the first semiconductor layer.
12. The nano-structured light-emitting device of claim 1 , further comprising:
a reflective layer configured to reflect light emitted from the active layers.
13. The nano-structured light-emitting device of claim 1 , wherein the nanostructures have polypyramid shapes or rod shapes.
14. The nano-structured light-emitting device of claim 1 , wherein the nano-structured light-emitting device includes different nanostructures operative to emit light having different wavelength ranges.
15. A nano-structured light-emitting device comprising:
a first semiconductor layer doped to have a first conductivity type;
a mask layer disposed on the first semiconductor layer and comprising a plurality of through-holes;
a plurality of nanostructures protruding through the plurality of through-holes and each comprising a nanocore that is doped to have the first conductivity type, an active layer that encloses surfaces of the nanocore, and a second semiconductor layer that is doped to have a second conductivity type;
an electrode layer enclosing and covering the plurality of nanostructures, the electrode layer having a first surface facing the plurality of nanostructures; and
a plurality of resistant layers disposed on a second surface of the electrode layer opposite to the first surface, each resistant layer respectively corresponding to a nanostructure of the plurality of nanostructures, and electrically insulated from one another.
16. The nano-structured light-emitting device of claim 15 , wherein each active layer comprises a quantum well structure that is stacked as In a Ga 1-a N/Al x In y Ga 1-x-y N (0≦a,x,y≦1, x+y<1).