Full color OLED and method for fabricating the same
An organic light-emitting display is provided. The organic light-emitting display comprises a substrate having red, green and blue pixel regions, and first electrodes each located on the pixel regions. A red phosphorescent emission layer, a green phosphorescent emission layer and a blue fluorescent emission layer are respectively located on the first electrodes. A hole blocking layer is located on the red phosphorescent emission layer and the green phosphorescent emission layer but not the blue fluorescent emission layer. A second electrode is located on the hole blocking layer and the blue fluorescent emission layer.
1 . An organic light-emitting display comprising:
a substrate having red, green and blue pixel regions;
a plurality of first electrodes located on the pixel regions;
a red phosphorescent emission layer, a green phosphorescent emission layer and a blue fluorescent emission layer, each located on the first electrodes and corresponding to the respective red, green and blue pixel regions;
a hole blocking layer located on the red phosphorescent emission layer and the green phosphorescent emission layer, but not the blue fluorescent emission layer; and
a second electrode located on the hole blocking layer and the blue fluorescent emission layer.
2 . The organic light-emitting display according to claim 1 , wherein the red phosphorescent emission layer includes an organic material having a carbazole unit as a host material.
3 . The organic light-emitting display according to claim 2 , wherein the organic material is CBP (carbazole biphenyl).
4 . The organic light-emitting display according to claim 1 , wherein the red phosphorescent emission layer includes a dopant material selected from the group consisting of PQIr, PQIr(acac), PlQIr(acac), PtOEP and combinations thereof.
5 . The organic light-emitting display according to claim 1 , wherein the green phosphorescent emission layer includes an organic material having a carbazole unit as a host material.
6 . The organic light-emitting display according to claim 5 , wherein the organic material is CBP (carbazole biphenyl).
7 . The organic light-emitting display according to claim 1 , wherein the green phosphorescent emission layer includes Ir(ppy)3 as a dopant material.
8 . The organic light-emitting display according to claim 1 , wherein the blue fluorescent emission layer includes a material selected from the group consisting of DPVBi, spiro-DPVBi, spiro-6P, distyryl-benzene(DSB), distyryl-arylene (DSA), PFO-based polymers, PPV-based polymers and combinations thereof.
9 . The organic light-emitting display according to claim 1 , wherein the hole blocking layer has a HOMO(highly occupied molecular orbital) energy level of from 5.5 to 6.9 eV.
10 . The organic light-emitting display according to claim 9 , wherein the HOMO energy level of the hole blocking layer is from 5.7 to 6.7 eV.
11 . The organic light-emitting display according to claim 1 , wherein the hole blocking layer includes a material selected from the group consisting of BCP, BAlq, CF—X, CF—Y and combinations thereof.
12 . The organic light-emitting display according to claim 1 , wherein the hole blocking layer has a thickness of from 30 to 100 Å.
13 . The organic light-emitting display according to claim 1 , further comprising:
at least one of a first charge transport layer and a first charge injection layer disposed between the first electrode and the emission layer.
14 . The organic light-emitting display according to claim 1 , further comprising:
at least one of a second charge transport layer and a second charge injection layer disposed between the blue fluorescent emission layer and the second electrode or between the hole blocking layer and the second electrode
15 . A method of fabricating an organic light-emitting display, comprising:
providing a substrate having red, green and blue pixel regions;
forming first electrodes over the pixel regions;
forming a red phosphorescent emission layer, a green phosphorescent emission layer and a blue fluorescent emission layer located on the first electrodes and corresponding to the respective red, green and blue pixel regions;
forming a hole blocking layer on the red phosphorescent emission layer and the green phosphorescent emission layer but not the blue fluorescent emission layer; and
forming a second electrode on the hole blocking layer and the blue fluorescent emission layer.
16 . The method according to claim 15 , wherein the blue fluorescent emission layer, the red phosphorescent emission layer and the green phosphorescent emission layer are formed by a method selected from the group consisting of laser induced thermal imaging (LITI) methods and vacuum deposition methods using a fine metal mask.
17 . The method according to claim 15 , wherein the hole blocking layer is formed by a vacuum deposition method using a fine metal mask.