Array substrate, fabrication method thereof and display device

Patent metadata

Field	Value
Publication number	US-9859350-B2
Application number	US-201515021459-A
Country	US
Kind code	B2
Filing date	Aug 12, 2015
Priority date	Apr 24, 2015
Publication date	Jan 2, 2018
Grant date	Jan 2, 2018

Abstract

An array substrate of an organic light-emitting display device, a fabrication method thereof and an organic light-emitting display device are provided. The array substrate comprises a plurality of pixel units arranged in array, wherein, at least one of the pixel units includes: an organic light-emitting diode ( 40 ) and a first thin film transistor ( 20 ) for controlling the organic light-emitting diode ( 40 ) which are formed on a base substrate ( 10 ), wherein, the organic light-emitting diode ( 40 ) includes a first electrode ( 107 ), a second electrode ( 110 ) and a light-emitting layer ( 109 ) located between the first electrode ( 107 ) and the second electrode ( 110 ), the first electrode ( 107 ) of the organic light-emitting diode ( 40 ) being connected with a drain electrode ( 104 ) of the first thin film transistor ( 20 ); and a conductive layer ( 111 ) and an insulating layer ( 112 ) formed between the first thin film transistor ( 20 ) and the organic light-emitting diode ( 40 ), wherein, the first electrode ( 107 ) of the organic light-emitting diode ( 40 ), the insulating layer ( 111 ) and the conductive layer ( 112 ) form a capacitor, and the conductive layer ( 111 ) is connected with a first gate electrode ( 100 ) of the first thin film transistor ( 20 ). The array substrate of the organic light-emitting display device, the fabrication method thereof and the organic light-emitting display device can effectively increase a storage capacitance value of a pixel unit, so as to improve display quality.

First claim

The invention claimed is:

1. An array substrate of an organic light-emitting display device, comprising a pixel unit defined by a gate line, a source line and two data line, the pixel unit including:
an organic light-emitting diode and a first thin film transistor for controlling the organic light-emitting diode which are formed on a base substrate, wherein, the organic light-emitting diode includes a first electrode, a second electrode and a light-emitting layer located between the first electrode and the second electrode, the first electrode of the organic light-emitting diode being electrically connected with a drain electrode of the first thin film transistor; and
a conductive layer and an insulating layer formed between the first thin film transistor and the organic light-emitting diode, wherein, the first electrode of the organic light-emitting diode, the insulating layer and the conductive layer form a capacitor, and the conductive layer is electrically connected with a first gate electrode of the first thin film transistor
wherein, the conductive layer covers at least a part of one of the data lines, and each of the data lines has a substantially constant width.

2. The array substrate according to claim 1 , wherein, the conductive layer covers the first thin film transistor.

3. The array substrate according to claim 1 , wherein, the first thin film transistor is formed between the organic light-emitting diode and the base substrate.

4. The array substrate according to claim 3 , wherein, an outer edge of a vertical projection of the conductive layer on the base substrate does not exceed an outer edge of a vertical projection of the first electrode of the organic light-emitting diode on the base substrate.

5. The array substrate according to claim 3 , further comprising a planarization layer formed between the first thin film transistor and the conductive layer.

6. The array substrate according to claim 5 , wherein the planarization layer is a resin layer, and has a thickness in a range of 1 to 2 microns.

7. The array substrate according to claim 1 , wherein, the first electrode of the organic light-emitting diode, the insulating layer and the conductive layer form an optical resonant micro-cavity configured to generate a resonant enhancement for light having a wavelength of λ emitted by the organic light-emitting diode and reflect the light out of the pixel unit.

8. The array substrate according to claim 7 , wherein, the conductive layer is made of a metal or an alloy, the insulating layer has a refractive index n1 in a range of 1.4 to 1.5, the first electrode of the organic light-emitting diode is made of a transparent conductive oxide material having a refractive index in a range of 1.6 to 2.1, and a thickness L of the insulating layer satisfies a formula of L=n1/2λ.

9. The array substrate according to claim 8 , wherein, the conductive layer is made of sliver or aluminum neodymium alloy, the insulating layer is made of silicon oxide, and the first electrode of the organic light-emitting diode is made of indium tin oxide or indium zinc oxide.

10. The array substrate according to claim 1 , wherein, the first electrode of the organic light-emitting diode includes a metal reflecting layer and a conductive metal oxide layer, and the conductive metal oxide layer being formed on a side of the metal reflecting layer opposite to the insulating layer.

11. The array substrate according to claim 1 , wherein, the first thin film transistor has a dual-gate structure, and the conductive layer is configured to be a second gate different from the first gate of the first gate electrode transistor.

12. The array substrate according to claim 11 , further comprising a planarization layer formed between the first thin film transistor and the conductive layer, wherein, the planarization layer includes an opening, a vertical projection of the first gate electrode of the first thin film transistor on the base substrate is located within a vertical projection of the opening on the base substrate, and at least a part of the conductive layer is filled in the opening.

13. The array substrate according to claim 1 , wherein, the first electrode and the second electrode of the organic light-emitting diode are an anode and a cathode respectively.

14. The array substrate according to claim 1 , wherein, the first thin film transistor is a thin film transistor of bottom-gate type or a thin film transistor of back channel etching type.

15. The array substrate according to claim 1 , wherein, an active layer of the first thin film transistor is an oxide active layer.

16. An organic light-emitting display device, comprising the array substrate according to claim 1 .

17. A fabrication method of an array substrate of an organic light-emitting display device, comprising:
forming a first thin film transistor and an organic light-emitting diode in a pixel region on a base substrate, the pixel region being defined by a gate line, a source line and two data lines; and
forming a conductive layer and an insulating layer between the first thin film transistor and the organic light-emitting diode; wherein, the organic light-emitting diode includes a first electrode, a second electrode and a light-emitting layer located between the first electrode and the second electrode, the first electrode of the organic light-emitting diode being electrically connected with a drain electrode of the first thin film transistor; the first electrode of the organic light-emitting diode, the insulating layer and the conductive layer form a capacitor, and the conductive layer is electrically connected with a first gate electrode of the first thin film transistor,
wherein, the conductive layer covers at least a part of one of the data lines, and each of the data lines has a substantially constant width.

18. The fabrication method of the array substrate according to claim 17 , wherein, the conductive layer covers the first thin film transistor.

19. The fabrication method of the array substrate according to claim 17 , further comprising forming a planarization layer between the conductive layer and the organic light-emitting diode.

20. The fabrication method of the array substrate according to claim 19 , wherein, the planarization layer has an opening, a vertical projection of the first gate electrode of the first thin film transistor on the base substrate is located within a vertical projection of the opening on the base substrate, and at least a part of the conductive layer is filled in the opening, so that the conductive layer forms a second gate different from the first gate of the first gate electrode transistor.

Assignees

• Boe Technology Group Co Ltd

Inventors

• Li Yongqian
• Wang Longyan
• Gai Cuili

Classifications

• H10D30/6734

  having gate electrodes arranged on both top and bottom sides of the channel, e.g. dual-gate TFTs · CPC title

• H01L29/78648

  Electricity · mapped topic

• H01L51/5265

  Electricity · mapped topic

• H01L2251/558

  Electricity · mapped topic

• H01L27/3265

  Electricity · mapped topic