Active-driving type organic EL display device, and a method of producing the same

• US 6,995,736 B2
• Filed: 03/05/2001
• Issued: 02/07/2006
• Est. Priority Date: 03/07/2000
• Status: Expired due to Term

• Current Assignee: Idemitsu Kosan Company Limited
• Original Assignee: Idemitsu Kosan Company Limited
• Inventors: Eida, Mitsuru
• Primary Examiner(s): Edouard, Patrick N.
• Assistant Examiner(s): NGUYEN, KIMNHUNG T
• Application Number:
  US09/959,601
• Publication Number:
  US 20050110716A1
• Time in Patent Office: 1,800 Days
• Field of Search: 345 45- 47, 345/76, 345/169.4, 315/169.1, 315/169.3, 315/169.4
• US Class Current: 345/76
• CPC Class Codes: G09G 2300/08 Active matrix structure, i.e. with use of active elements, inclusive of non-linear two terminal elements, in the pixels together with light emitting or modulating elements
• CPC Class Codes: G09G 2300/0842 forming a memory circuit, e.g. a dynamic memory with one capacitor
• CPC Class Codes: G09G 3/3225 using an active matrix
• CPC Class Codes: H10K 50/865 comprising light absorbing layers, e.g. light-blocking layers
• CPC Class Codes: H10K 59/123 Connection of the pixel electrodes to the thin film transistors [TFT]
• CPC Class Codes: H10K 59/38 comprising colour filters or colour changing media [CCM]
• CPC Class Codes: H10K 59/8792 comprising light absorbing layers, e.g. black layers
• CPC Class Codes: H10K 85/141 comprising aliphatic or olefinic chains, e.g. poly N-vinylcarbazol, PVC or PTFE

Abstract

An organic EL display device and a method of producing the same wherein superior connection reliability can be obtained between a thin film transistor and a lower electrode of an organic EL element even if a color-converting medium is provided adjacent light-emitting face of the organic EL element. For this purpose, in an active-driving type organic EL display device comprising an organic EL element made so as to have an organic luminous medium sandwiched between an upper electrode and a lower electrode, and a thin film transistor for controlling luminescence of the organic EL element, the luminescence of the organic EL element is taken out from the lower electrode, a color-converting medium is provided adjacent the lower electrode, and an inclined electrically connecting member is set between the lower electrode and the thin film transistor.

Claims

1. An active-driving type organic EL display device, comprising an organic EL element made so as to have an organic luminous medium sandwiched between an upper electrode and a lower electrode, and a thin film transistor for controlling luminescence of the organic EL element, wherein

the luminescence of the organic EL element is taken out from the lower electrode,

a color-converting medium is provided adjacent the lower electrode, and

the lower electrode is connected to the thin film transistor by an inclined electrically connecting member across a level difference between the lower electrode and the thin film transistor, the level difference being generated by the color-converting medium.

2. The active-driving type organic EL display device according to claim 1, wherein an inclination angle of the electrically connecting member to a horizontal plane is set to a value within the range of 10°

to 80°

.

3. The active-driving type organic EL display device according to claim 1, wherein an inclined plane is formed in the color-converting medium, and the electrically connecting member is disposed along the inclined plane.

4. The active-driving type organic EL display device according to claim 1, wherein an oblique member for inclining the electrically connecting member is disposed at a side end of the color-converting medium.

5. The active-driving type organic EL display device according to claim 1, wherein the electrically connecting member is a via hole formed in an inter-insulator between the organic EL element and the thin film transistor.

6. The active-driving type organic EL display device according to claim 1, wherein the electrically connecting member is an electric wire made of a sintered electro-conductive paste.

7. The active-driving type organic EL display device according to claim 1, wherein the electrically connecting member is a bonding wire.

8. The active-driving type organic EL display device according to claim 1, wherein the electrically connecting member is made of indium zinc oxide (IZO).

9. The active-driving type organic EL display device according to claim 1, wherein the lower electrode is made of indium zinc oxide or indium tin oxide.

10. The active-driving type organic EL display device according to claim 9, wherein the lower electrode and the electrically connecting member are integrally made of a non-crystalline electro-conductive oxide.

11. The active-driving type organic EL display device according to claim 1, wherein a part of the electrically connecting member is provided with a metallized portion.

12. The active-driving type organic EL display device according to claim 1, wherein the thickness of the electrically connecting member is set to a value within the range of 0.01 to 100 μ

m.

13. A method of producing an active-driving type organic EL display device of claim 1 comprising an organic EL element made so as to have an organic luminous medium sandwiched between an upper electrode and a lower electrode, a color-converting medium for converting color of EL luminescence taken out from the lower electrode, and a thin film transistor for controlling luminescence of the organic EL element, comprising the steps of:

forming the thin film transistor,

forming the color-converting medium,

forming the electrically connecting member so as to be inclined, and

forming the organic EL element.

14. The method of producing the active-driving type organic EL display device according to claim 13, further comprising the step of making an inclined plane in a part of the color-converting medium, and

wherein the electrically connecting member is provided along the inclined plane.

15. The method of producing the active-driving type organic EL display device according to claim 13, wherein the lower electrode and the electrically connecting member are integrally made of the non-crystalline electro-conductive oxide.

16. The method of producing the active-driving type organic EL display device according to claim 13, wherein the electrically connecting member is formed by a vacuum vapor deposition method or a sputtering method.

17. The method of producing the active-driving type organic EL display device according to claim 13, wherein the electrically connecting member is formed by a sol-gel method.

18. The method of producing the active-driving type organic EL display device according to claim 13, further comprising the step of metallizing at least a part of the electrically connecting member.

19. An active-driving type organic EL display device, comprising an organic EL element made so as to have an organic luminous medium sandwiched between an upper electrode and a lower electrode, and a thin film transistor for controlling luminescence of the organic EL element, wherein

the luminescence of the organic EL element is taken out from the lower electrode, the color-converting medium is provided adjacent the lower electrode, and

a position adjusting layer for adjusting a height position of the thin film transistor between the thin film transistor and the supporting substrate is provided.