Organic electroluminescent display device

• US 6,870,186 B2
• Filed: 12/30/2002
• Issued: 03/22/2005
• Est. Priority Date: 04/25/2002
• Status: Expired due to Term

• Current Assignee: LG Philips LCD Company Limited (LG Display Co., Ltd.)
• Original Assignee: LG Philips LCD Company Limited (LG Display Co., Ltd.)
• Inventors: Park, Jae Yong, Yoo, Choong Keun, Kim, Ock Hee, Kim, Kwan Soo, Lee, Nam Yang
• Primary Examiner(s): Nelms, David
• Assistant Examiner(s): HO, TU TU V
• Application Number:
  US10/330,310
• Publication Number:
  US 20030201445A1
• Time in Patent Office: 813 Days
• Field of Search: 257/59, 257/72, 257/40, 257/E39.007
• US Class Current: 257/59
• CPC Class Codes: H10K 2102/3026 Top emission
• CPC Class Codes: H10K 50/841 Self-supporting sealing arrangements
• CPC Class Codes: H10K 59/122 Pixel-defining structures or layers, e.g. banks
• CPC Class Codes: H10K 59/1275 Electrical connections of the two substrates
• CPC Class Codes: H10K 59/35 comprising red-green-blue [RGB] subpixels
• CPC Class Codes: H10K 59/38 comprising colour filters or colour changing media [CCM]
• CPC Class Codes: H10K 59/873 Encapsulations

Abstract

An organic electroluminescent device includes first and second substrates attached by a seal pattern, array elements including a plurality of thin film transistors formed on the first substrate, a first electrode formed on a rear surface of the second substrate, a plurality of electrode separators formed on the rear surface of the first electrode, wherein the plurality of electrode separators is made of an insulating material defining sub-pixel regions that correspond to each thin film transistor, an organic electroluminescent layer formed on a rear surface of the first electrode in each of the sub-pixel regions, a second electrode formed on a rear surface of the organic electroluminescent layer in each of sub-pixel regions, a conductive connector formed between the first and second substrates in each sub-pixel region for connecting to the second electrode of a sub-pixel region.

Claims

1. An organic electroluminescent device, comprising:

first and second substrates attached by a seal pattern;

array elements including a plurality of thin film transistors formed on the first substrate;

a first electrode formed on a rear surface of the second substrate;

a plurality of electrode separators formed on the rear surface of the first electrode, wherein the plurality of electrode separators is made of an insulating material defining sub-pixel regions that correspond to each thin film transistor,

an organic electroluminescent layer formed on a rear surface of the first electrode in each of the sub-pixel regions;

a second electrode formed on a rear surface of the organic electroluminescent layer in each of sub-pixel regions; and

a conductive connector formed within a cell gap between the first and second substrates in each sub-pixel region for connecting to the second electrode of a sub-pixel region.

2. The device according to claim 1, wherein the conductive connector contacts each thin film transistor and has a planar top surface that contacts the second electrode.

3. The device according to claim 1, wherein each thin film transistor comprises:

a semiconductor layer;

a gate insulation layer on the semiconductor layer;

a gate electrode on the gate insulation layer, wherein gate electrode is disposed above a central part of the semiconductor layer;

a passivation layer covering both the semiconductor layer and the gate electrode, and having first and second contact holes that expose the semiconductor layer on both sides of the gate electrode;

a source electrode on the passivation layer that contacts the semiconductor layer through the first contact hole; and

a drain electrode on the passivation layer that contacts the semiconductor layer through the second contact hole.

4. The device according to claim 1, wherein the first electrode is anode, the second electrode is cathode, and the organic electroluminescent layer includes a hole injection layer, a hole transporting layer, a luminous layer, an electron transporting layer and an electron injection layer in series from the first electrode.

5. The device according to claim 1, further comprising a buffer electrode between the plurality of conductive connectors and the second electrode.

6. The device according to claim 5, wherein the buffer electrode is made of metallic material including aluminum.

7. The device according to claim 1, wherein the each conductive connector is a double-layered structure having a first metal layer and a second metal layer.

8. The device according to claim 7, wherein the first metal layer is a metallic material having a lower specific resistance than the second metal layer.

9. The device according to claim 8, wherein the second metal layer is metallic material having a larger ductility than the first metal layer.

10. The device according to claim 8, further comprising a buffer electrode between each conductive connector and the second electrode.

11. The device according to claim 10, wherein the buffer electrode is made of metallic material including aluminum.

12. The device according to claim 1, wherein the each conductive connector is a multi-layered structure having a plurality of metal layers.

13. The device according to claim 1, wherein the first electrode, the organic electroluminescent layer and the second electrode constitute an organic electroluminescent diode that emits light in a direction toward the second substrate.

14. The device according to claim 1, wherein the cell gap between the first and second substrates containing an inert gas.

15. The device according to claim 1, wherein each conductive connector has a trapezoidal like shaped taper.

16. The device according to claim 1, wherein the first electrode is made of a transparent conductive material and the second electrode is made of an opaque metallic material.

17. An organic electroluminescent device, comprising:

first and second substrates attached by a seal pattern;

array elements including a plurality of thin film transistors formed on the first substrate;

a color changing medium formed on a rear surface of the second substrate, wherein the color changing medium has a black matrix that defines sub-pixel regions having red, green and blue color changing layers respectively corresponding to each sub-pixel region of a pixel;

a first electrode attached on a rear surface of the color changing medium;

an organic electroluminescent layer formed on a rear surface of the first electrode, wherein the organic electroluminescent layer emits blue light;

a second electrode formed on a rear surface of the organic electroluminescent layer, the second electrode corresponding to the sub-pixel region;

a plurality of electrode separators on the rear surface of the first electrode corresponding in position to the black matrix in defining the sub-pixel regions; and

a plurality of conductive connectors formed between the first and second substrates, each conductive connector electrically connecting an array element to the second electrode in each sub-pixel region.

18. The device according to claim 17, wherein the first electrode is anode, the second electrode is cathode, and the organic electroluminescent layer includes a hole injection layer, a hole transporting layer, a luminous layer, an electron transporting layer and an electron injection layer in series from the first electrode.

19. The device according to claim 17, wherein the conductive connector is a double-layered structure having a first metal layer and a second metal layer.

20. The device according to claim 19, wherein the first metal layer is a metallic material having a lower specific resistance than the second metal layer.

21. The device according to claim 20, wherein the second metal layer is metallic material having a higher ductility than the first metal layer.

22. The device according to claim 21, further comprising a buffer electrode between each conductive connector and the second electrode.

23. The device according to claim 22, wherein the buffer electrode is made of metallic material including aluminum.

24. The device according to claim 17, wherein the conductive connector is a multi-layered structure having a plurality of metal layers.

25. The device according to claim 17, wherein the first electrode, the organic electroluminescent layer and the second electrode constitute an organic electroluminescent diode that emits light in a direction toward the second substrate.

26. The device according to claim 17, wherein a cell gap between the first and second substrates contains an inert gas.

27. The device according to claim 17, wherein each conductive connector has a trapezoidal like shaped taper.

28. The device according to claim 17, wherein the first electrode is made of a transparent conductive material and the second electrode is magic of an opaque metallic material.