Nanorod light emitting device, method of manufacturing the same, and display apparatus including the same
A nanorod light emitting device includes a semiconductor light emitting nanorod, and a passivation film surrounding a sidewall of the semiconductor light emitting nanorod and having insulating properties, wherein the passivation film includes an insulating crystalline material having a same crystal structure as a crystal structure of the semiconductor light emitting nanorod.
1. A nanorod light emitting device comprising:
a semiconductor light emitting nanorod;
a passivation film surrounding a sidewall of the semiconductor light emitting nanorod and having insulating properties,
wherein the passivation film comprises an insulating crystalline material having a substantially same crystal structure as a crystal structure of the semiconductor light emitting nanorod,
an amorphous insulating layer directly in contact with a sidewall of the passivation film; and
further comprising a protective film disposed between the semiconductor light emitting nanorod and the passivation film to directly surround the sidewall of the semiconductor light emitting nanorod,
wherein the protective film comprises an insulating crystalline material having the substantially same crystal structure as the crystal structure of the semiconductor light emitting nanorod,
wherein an energy bandgap of the protective film is greater than an energy bandgap of the semiconductor light emitting nanorod, and
wherein an energy bandgap of the passivation film is greater than or equal to the energy bandgap of the protective film.
2. The nanorod light emitting device of claim 1 ,
wherein the passivation film has a lattice matching epitaxy relationship or a domain matching epitaxy relationship with the semiconductor light emitting nanorod.
3. The nanorod light emitting device of claim 2 ,
wherein a difference between a lattice constant of the passivation film and a lattice constant of the semiconductor light emitting nanorod is within +30% of the lattice constant of the semiconductor light emitting nanorod.
4. The nanorod light emitting device of claim 2 ,
wherein a difference between a lattice constant of the passivation film and an integer multiple of a lattice constant of the semiconductor light emitting nanorod is within +30% of the lattice constant of the semiconductor light emitting nanorod.
5. The nanorod light emitting device of claim 1 ,
wherein an energy bandgap of the passivation film is greater than an energy bandgap of the semiconductor light emitting nanorod.
6. The nanorod light emitting device of claim 1 ,
wherein the passivation film comprises at least one from among ZrO, SrO, MgO, BaO, CeO 2 , Gd 2 O 3 , CaO, HfO 2 , TiO 2 , AlO x , BaN, SiN, TiN, CeN, AlN, ZnSe, ZnS, AlGaN, and Al x Ga 1-x As (x≥0.9).
7. The nanorod light emitting device of claim 1 ,
wherein a thickness of the passivation film is in a range of about 5 nm to about 20 nm.
8. The nanorod light emitting device of claim 1 ,
wherein a thickness of the protective film is in a range of about 0.5 nm to about 5 nm and smaller than a thickness of the passivation film.
9. The nanorod light emitting device of claim 1 ,
wherein a thickness of the insulating film is in a range of about 40 nm to about 70 nm.
10. The nanorod light emitting device of claim 1 ,
wherein an energy bandgap of the insulating film is greater than an energy bandgap of the passivation film.
11. The nanorod light emitting device of claim 1 , wherein the semiconductor light emitting nanorod comprises:
a first semiconductor layer doped with a first impurity of a first conductivity type;
a light emitting layer disposed on the first semiconductor layer; and
a second semiconductor layer disposed on the light emitting layer and doped with a second impurity of a second conductivity type electrically opposite to the first conductivity type.
12. The nanorod light emitting device of claim 11 ,
wherein the semiconductor light emitting nanorod further comprises a transparent electrode disposed on the second semiconductor layer.
13. The nanorod light emitting device of claim 1 ,
wherein the semiconductor light emitting nanorod has a height in a range of about 1 μm to about 20 μm, and an outer diameter in a range of about 0.05 μm to about 2 μm.
14. A display apparatus comprising:
a pixel electrode;
a common electrode;
a nanorod light emitting device disposed between the pixel electrode and the common electrode,
wherein the nanorod light emitting device comprises:
a semiconductor light emitting nanorod; and
a passivation film surrounding a sidewall of the semiconductor light emitting nanorod and having insulating properties, and
wherein the passivation film comprises an insulating crystalline material having a substantially same crystal structure as a crystal structure of the semiconductor light emitting nanorod, and
an amorphous insulating layer directly in contact with a sidewall of the passivation film, and
wherein the nanorod light emitting device further comprises a protective film disposed between the semiconductor light emitting nanorod and the passivation film to directly surround the sidewall of the semiconductor light emitting nanorod,
wherein the protective film comprises an insulating crystalline material having the substantially same crystal structure as the crystal structure of the semiconductor light emitting nanorod,
wherein an energy bandgap of the protective film is greater than an energy bandgap of the semiconductor light emitting nanorod, and
wherein an energy bandgap of the passivation film is greater than or equal to the energy bandgap of the protective film.
15. A cylindrical light emitting device comprising:
a first cylindrical semiconductor layer;
a second cylindrical semiconductor layer;
a cylindrical active layer between the first cylindrical semiconductor layer and the second cylindrical semiconductor layer; and
a passivation film surrounding a sidewall of the cylindrical active layer,
wherein the passivation film comprises an insulating crystalline material, and
an amorphous insulating layer directly in contact with a sidewall of the passivation film, and
wherein the first cylindrical semiconductor layer, the second cylindrical semiconductor layer, the cylindrical active layer, and the passivation film have a substantially same crystal structure,
the cylindrical light emitting device further comprising a protective film disposed between the second cylindrical semiconductor layer and the passivation film to directly surround the sidewall of the second cylindrical semiconductor layer,
wherein the protective film comprises an insulating crystalline material having the substantially same crystal structure as the crystal structure of the second cylindrical semiconductor layer, and
wherein an energy bandgap of the passivation film is greater than or equal to the energy bandgap of the protective film.
16. The cylindrical light emitting device of claim 15 , wherein the cylindrical light emitting device has a height in a range of about 1 μm to about 20 μm, and an outer diameter in a range of about 0.05 μm to about 2 μm.