Organic light-emitting display device with spacer between sub-pixels
Disclosed is an organic light-emitting display device, which prevents lateral current leakage by providing a structure on a bank so as to cut off an organic material, which is formed in a subsequent process, around the structure.
1 . An organic light-emitting display device comprising:
a substrate including a plurality of pixels, each pixel comprising a first sub-pixel, a second sub-pixel and a third sub-pixel, each of the first to third sub-pixels having an emission portion and a non-emission portion surrounding the emission portion;
a first electrode on the emission portion of each of the first to third sub-pixels;
a bank on the non-emission portion;
a first spacer having a negatively tapered shape and provided on the bank at least between the first sub-pixel and the second sub-pixel;
a second spacer placed between the second sub-pixel and the third sub-pixel, wherein the second spacer is higher than the first spacer;
an organic stack above the first electrode and the first spacer, wherein the organic stack on the first electrode is spaced from sides of the first electrode; and
a second electrode disposed on the organic stack,
wherein a length of the first spacer in a first direction is shorter than a dimension of the first sub-pixel in the first direction, the second sub-pixel and the third sub-pixel separated from the first sub-pixel in a second direction crossing the first direction, and
wherein the first spacer is placed to block the emission portion of the second sub-pixel from the emission portion of the first sub-pixel.
2 . The device according to claim 1 , wherein the length of the first spacer in the first direction is greater than a dimension of the emission portion of the second sub-pixel in the first direction.
3 . The device according to claim 1 , wherein the second sub-pixel and the third sub-pixel are alternately disposed in the first direction, and wherein the first spacer extends between the first sub-pixel and the third sub-pixel.
4 . The device according to claim 3 , wherein the first sub-pixel extends in the first direction at least to an edge of the third sub-pixel, the edge located at a side of the third pixel away from the second sub-pixel.
5 . The device according to claim 1 , wherein the first spacer comprises a first segment between the first sub-pixel and the second sub-pixel and a second segment between the second sub-pixel and the third sub-pixel, wherein the first segment and the second segment are directly connected.
6 . The device according to claim 5 , wherein the second segment is longer than a dimension of the second sub-pixel or a dimension of the third sub-pixels in the second direction.
7 . The device according to claim 1 , wherein the first spacer comprises a first segment between the first sub-pixel and the second sub-pixel, and a second segment between the first sub-pixel and the third sub-pixel, and the first segment and the second segment are separated in the first direction.
8 . The device according to claim 1 , wherein the first spacer has a width ranging from 1 μm to 5 μm in the second direction crossing the first direction.
9 . The device according to claim 1 , wherein a threshold voltage of the first sub-pixel is higher than a threshold voltage of the second sub-pixel.
10 . The device according to claim 1 , wherein the second sub-pixel and the third sub-pixel smaller than the first sub-pixel.
11 . The device according to claim 1 , wherein the organic stack includes a hole injection layer contacting the first electrode and at least one stack, each of the at least one stack including a sequential stack of a hole transport layer, a light-emitting layer, and an electron transport layer.
12 . The device according to claim 11 , wherein the organic stack comprises a plurality of stacks, each of the stack including a sequential stack of a hole transport layer, a light-emitting layer and an electron transport layer, the device further including a charge generation layer between the plurality of stacks.
13 . The device according to claim 11 , wherein at last one layer of the organic stack has a gap at sides of the first spacer.
14 . The device according to claim 11 , wherein at least one layer of the organic stack on the first spacer has an island shape.
15 . The device according to claim 1 , wherein the first sub-pixel is a blue sub-pixel, the second sub-pixel is a red sub-pixel, and the third sub-pixel is a green sub-pixel.
16 . An organic light emitting device, comprising:
a first sub-pixel in a pixel configured to emit light of a first color, the first sub-pixel comprising two first electrodes and a first portion of an organic stack sandwiched between the two first electrodes;
a second sub-pixel adjacent to and spaced apart from the first sub-pixel in the pixel, the second sub-pixel configured to emit light of a second color, the second sub-pixel comprising two second electrodes and a second portion of the organic stack sandwiched between the two second electrodes;
a third sub-pixel configured to emit light of a third color, the third sub-pixel comprising two third electrodes and a third portion of the organic stack sandwiched between the two third electrodes, wherein the second sub-pixel and the third sub-pixel are alternately disposed in a first direction, adjacent to the first sub-pixel;
a first spacer between the first sub-pixel and the second sub-pixel, the first spacer placed to block the second portion of the organic stack of the second sub-pixel from the first portion of the organic stack of the first sub-pixel; and
a second spacer placed between the second sub-pixel and the third sub-pixel, wherein the second spacer is higher than the first spacer,
wherein a length of the first spacer in the first direction is shorter than a dimension of an emission portion of the first sub-pixel in the first direction, the second sub-pixel separated from the first sub-pixel in a second direction crossing the first direction.
17. A method of manufacturing an organic light-emitting display device, the method comprising:
forming a plurality of pixels on a substrate, the plurality of pixels comprising a first sub-pixel, a second sub-pixel and a third sub-pixel, each of the first to third sub-pixels having an emission portion and a non-emission portion;
forming a first electrode on the emission portion of each of the first to third sub-pixels;
forming a bank on the non-emission portion;
forming a first spacer between the emission portion of the first sub-pixel and the emission portion of the second sub-pixel to block the emission portion of the second sub-pixel from the emission portion of the first sub-pixel;
forming a second spacer between the second sub-pixel and the third sub-pixel, wherein the second spacer is higher in height than the first spacer;
forming an organic stack above the first electrode and the first spacer, wherein the organic stack has at least two stacks, and a charge generation layer between the stacks; and
forming a second electrode on the organic stack,
wherein a length of the first spacer is smaller than a length of the emission portion of the first sub-pixel.
18. The method according to claim 17 , further comprising forming a capping layer on the second electrode.
19. The method according to claim 18 , wherein at least one of the organic stack, the second electrode, and the capping layer has a disconnected portion on at least one side of the first spacer.
20. The method according to claim 18 , wherein at least one of the organic stack, the second electrode, and the capping layer has an island shape.
21. The method according to claim 17 , wherein a first thickness of a first color light-emitting layer of the first sub-pixel is different from a second thickness of a second color light-emitting layer of the second sub-pixel, and the second thickness of the second color light-emitting layer of the second sub-pixel is different from a third thickness of a third color light-emitting layer of the third sub-pixel.
22. The method according to claim 17 , wherein the charge generation layer comprises a p-type charge generation layer and an n-type charge generation layer.
23. The method according to claim 17 , wherein a length of the first spacer in a first direction is shorter than a length of the emission portion of the first sub-pixel in the first direction and longer than a length of the emission portion of the second sub-pixel.
24. The method according to claim 17 , wherein the first spacer comprises a first segment and a second segment.
25. The method according to claim 17 , wherein the first spacer comprises a first segment between the first sub-pixel and the second sub-pixel, and a second segment between the first sub-pixel and the third sub-pixel.
26. The method according to claim 17 , wherein a threshold voltage of the first sub-pixel is highest among the first to third sub-pixels.
27. The method according to claim 17 , wherein a size of the second spacer is different from a size the first spacer.
28. The method according to claim 17 , wherein at least one layer of the organic stack is disconnected at the first spacer and has a gap between the first sub-pixel and the second sub-pixel.
29. The method according to claim 17 , wherein a portion of the first electrode extends beyond the emission portion and overlaps with the bank.
30. The method according to claim 17 , wherein the first electrode is larger than the emission portion and covers at least the emission portion.
31. The method according to claim 17 , wherein the bank is integrally formed with the first spacer or the second spacer.
32. The method according to claim 17 , wherein the bank, the first spacer, and the second spacer are separately patterned.
33. The method according to claim 17 , wherein the first spacer is 1 μm to 1.5 μm in height, and the second spacer is 1.7 μm to 2.5 μm in height.
34. The method according to claim 17 , wherein a width of the first spacer in a direction from the first sub-pixel to the second sub-pixel is 1 μm to 5 μm.
35. The method according to claim 17 , wherein the organic stack includes an electron blocking layer or a hole blocking layer.