Display device and method of making display device
View Patent ↗A display device with increased lifespan is presented. The device includes a plurality of thin film transistors, a passivation layer formed on the thin film transistors, a plurality of pixel electrodes formed on the passivation layer and electrically connected to the thin film transistors, and a wall dividing the pixel electrodes. The wall has a main section and an auxiliary section that is lower than the main section. A caved-in section is disposed between the main section and the auxiliary section. An organic layer is formed on the pixel electrodes.
1. A display device comprising:
a plurality of thin film transistors;
a passivation layer formed on the thin film transistors;
a plurality of pixel electrodes formed on the passivation layer and electrically connected to the thin film transistors;
a wall dividing the pixel electrodes, the wall having a main wall and an auxiliary wall that is lower than the main wall, a caved-in part being disposed between the main wall and the auxiliary wall; and
an organic layer formed on the pixel electrodes.
2. The display device according to claim 1 , wherein the organic layer is deposited over the auxiliary wall and the caved-in part.
3. The display device according to claim 1 , further comprising a common electrode disposed on the organic layer.
4. The display device according to claim 3 , wherein the common electrode directly contacts an upper surface of the main wall.
5. The display device according to claim 1 , wherein the height of the main wall is in the range of about 0.5 μm to about 5 μm.
6. The display device according to claim 1 , wherein the height of the auxiliary wall is in the range of about 0.25 μm to about 4.5 μm.
7. The display device according to claim 1 , wherein the height of the auxiliary wall is about 50% to about 90% of the height of the main wall.
8. The display device according to claim 1 , wherein the width of the caved-in part is in the range of about 0.5 μm to about 10 μm.
9. The display device according to claim 1 , wherein the depth of the caved-in part is about 50% to about 300% of the width of the caved-in part.
10. The display device according to claim 1 , wherein the width of the wall is in the range of about 40 μm to about 60 μm.
11. The display device according to claim 1 , wherein the auxiliary wall comprises a pair of auxiliary walls flanking the main wall.
12. The display device according to claim 1 , wherein the wall is formed over one of the thin film transistors.
13. The display device according to claim 1 , wherein the organic layer comprises a hole-injecting layer and a light-emitting layer.
14. The display device according to claim 13 , wherein the thickness of the hole-injecting layer is in the range of about 50 nm to about 400 nm.
15. The display device according to claim 13 , wherein the thickness of the light-emitting layer is in the range of about 50 nm to about 400 nm.
16. The display device according to claim 13 , further comprising an intermediate layer disposed between the hole-injecting layer and the light-emitting layer.
17. The display device according to claim 16 , wherein the hole-injecting layer comprises poly-3,4-ethylenedioxythiophene.
18. The display device according to claim 1 , wherein the wall further comprises a flat part disposed between the main wall and the caved-in part, the flat part being substantially parallel to the pixel electrode.
19. The display device according to claim 18 , wherein the height of the flat part is substantially the same as the height of the auxiliary wall.
20. A method of making a display device comprising:
providing a plurality of thin film transistors and a passivation layer on an insulating substrate;
providing a plurality of pixel electrodes electrically connected to the thin film transistors on the passivation layer;
forming a wall dividing the pixel electrodes, the wall having a main wall and an auxiliary wall that is lower than the main wall, a caved-in part being disposed between the main wall and the auxiliary wall; and
forming an organic layer on the pixel electrodes.
21. The method of making the display device according to claim 20 , wherein forming the organic layer comprises depositing a polymer solution by an ink-jet method.
22. The method of making the display device according to claim 21 , wherein depositing the polymer solution comprises disposing at least some of the polymer solution in the caved-in part.
23. The method of making the display device according to claim 21 , wherein forming the organic layer comprises disposing the polymer solution to a level higher than the auxiliary wall.
24. The method of making the display device according to claim 21 , wherein forming the organic layer comprises disposing the polymer solution at varying levels as a function of distance from the wall, the level of polymer solution increasing with distance from the wall.
25. The method of making the display device according to claim 20 , further comprising forming a common electrode on the organic layer.
26. The method of making the display device according to claim 20 , wherein forming the wall comprises using either a slit mask exposing method or an imprinting method.