Organic light-emitting device, method of fabricating the same, and organic light-emitting display apparatus including the device

1. An organic light-emitting device, comprising:

a first electrode;

a second electrode facing the first electrode;

an emission layer between the first electrode and the second electrode;

a hole control layer between the first electrode and the emission layer; and

an electron control layer between the emission layer and the second electrode,

wherein:

the emission layer includes a plurality of sub-emission layers to emit light having different wavelength ranges,

at least portions of the plurality of sub-emission layers do not overlap one another,

the plurality of sub-emission layers include:

a first sub-emission layer including a first color light-emitting dopant, and

a second sub-emission layer including a second color light-emitting dopant different from the first color light-emitting dopant,

the first sub-emission layer and the second sub-emission layer each include a hole-transporting host and an electron-transporting host which form an exciplex, and

a triplet energy of the exciplex is equal to or greater than triplet energies of the first color light-emitting dopant and the second color light-emitting dopant.

2. The organic light-emitting device as claimed in claim 1 , wherein the first sub-emission layer and the second sub-emission layer include a same hole-transporting host and a same electron-transporting host.

3. The organic light-emitting device as claimed in claim 1 , wherein the triplet energy of the exciplex is about 2.4 eV to about 3.0 eV.

4. The organic light-emitting device as claimed in claim 1 , wherein a difference between a lowest unoccupied molecular orbital (LUMO) energy level of the hole-transporting host and a LUMO energy level of the electron-transporting host is about 0.2 eV or more.

5. The organic light-emitting device as claimed in claim 1 , wherein a difference between a highest occupied molecular orbital (HOMO) energy level of the hole-transporting host and a HOMO energy level of the electron-transporting host is about 0.2 eV or more.

6. The organic light-emitting device as claimed in claim 1 , wherein a weight ratio of the hole-transporting host to the electron-transporting host is about 80:20 to about 20:80.

7. The organic light-emitting device as claimed in claim 1 , wherein:

the plurality of sub-emission layers further include a third sub-emission layer that includes a third color light-emitting dopant, the third color light-emitting dopant being different from the first color light-emitting dopant and the second color light-emitting dopant, and

the third sub-emission layer includes the hole-transporting host and the electron-transporting host.

8. The organic light-emitting device as claimed in claim 7 , wherein:

the third color light-emitting dopant is a blue light-emitting dopant, and

a difference between a triplet energy level of the exciplex and a singlet energy level of the blue light-emitting dopant is about −0.1 eV to about 0.1 eV.

9. The organic light-emitting device as claimed in claim 7 , wherein each sub-emission layer of the plurality of sub-emission layers further includes an auxiliary layer.

10. The organic light-emitting device as claimed in claim 7 , wherein mixing ratios of the hole-transporting host and the electron-transporting host in the first to third sub-emission layers are each different from one another.

11. A method of fabricating an organic light-emitting device, the method comprising:

forming a hole control layer on a first electrode;

forming a plurality of sub-emission layers on the hole control layer, the plurality of sub-emission layers including a first sub-emission layer and a second sub-emission layer;

forming an electron control layer on the plurality of sub-emission layers; and

forming a second electrode on the electron control layer,

wherein forming the plurality of sub-emission layers includes:

providing a mixed host material including a hole-transporting host mixed with an electron-transporting host,

forming the first sub-emission layer by performing a first co-deposition of a first color light-emitting dopant and the mixed host material, and

forming the second sub-emission layer by performing a second co-deposition of the mixed host material and a second color light-emitting dopant, the second color light-emitting dopant being different from the first color light-emitting dopant,

wherein the mixed host material includes the hole-transporting host and the electron-transporting host which form an exciplex, and

wherein a triplet energy of the exciplex is equal to or greater than triplet energies of the first color light-emitting dopant and the second color light-emitting dopant.

12. The method as claimed in claim 11 , wherein forming the plurality of sub-emission layers further includes forming a third sub-emission layer by performing a third co-deposition of the mixed host material and a third color light-emitting dopant, the third color light-emitting dopant being different from the first color light-emitting dopant and different from the second color light-emitting dopant.

13. The method as claimed in claim 11 , further comprising providing an auxiliary layer on the hole control layer.

14. An organic light-emitting display apparatus, comprising:

a timing controller;

a scan driver;

a source driver; and

an organic light-emitting display panel, the organic light-emitting display panel including an organic light-emitting device, wherein the organic light-emitting device includes:

a first electrode;

a second electrode facing the first electrode;

an emission layer between the first electrode and the second electrode;

a hole control layer between the first electrode and the emission layer; and

an electron control layer between the emission layer and the second electrode,

wherein:

the emission layer includes a plurality of sub-emission layers to emit light having different wavelength ranges,

at least portions of the plurality of sub-emission layers do not overlap one another,

the plurality of sub-emission layers include:

a first sub-emission layer including a first color light-emitting dopant, and

a second sub-emission layer including a second color light-emitting dopant different from the first color light-emitting dopant,

the first sub-emission layer and the second sub-emission layer each include a hole-transporting host and an electron-transporting host which form an exciplex, and

a triplet energy of the exciplex is equal to or greater than triplet energies of the first color light-emitting dopant and the second color light-emitting dopant.

15. The organic light-emitting display apparatus as claimed in claim 14 , wherein:

the plurality of sub-emission layers further includes a third sub-emission layer,

the third sub-emission layer includes the hole-transporting host, the electron-transporting host, and a third color light-emitting dopant, the third color light-emitting dopant being different from the first color light-emitting dopant and the second color light-emitting dopant, and

a difference between a triplet energy level of the exciplex and a singlet energy level of the third light-emitting dopant is about −0.1 eV to about 0.1 eV.