Display devices including an oxide semiconductor thin film transistor

• US 8,102,476 B2
• Filed: 05/22/2008
• Issued: 01/24/2012
• Est. Priority Date: 12/03/2007
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Son, Kyoung-seok, Lee, Sang-yoon, Ryu, Myung-kwan, Kim, Tae-sang, Kwon, Jang-yeon, Park, Kyung-bae, Jung, Ji-sim
• Primary Examiner(s): Vu, Phu
• Application Number:
  US12/153,657
• Publication Number:
  US 20090141203A1
• Time in Patent Office: 1,342 Days
• Field of Search: 349 38- 39, 349/140
• US Class Current: 349/14
• CPC Class Codes: G02F 1/136213 Storage capacitors associated with the pixel electrode
• CPC Class Codes: G02F 2203/01 transmissive

Abstract

A display device including an oxide semiconductor thin film transistor is provided. The display device includes at least one thin film transistor, and at least one storage capacitor. The storage capacitor includes a storage electrode formed of a transparent oxide semiconductor, and a pixel electrode over the storage electrode. The pixel electrode may be separated from the storage electrode by a desired distance.

Claims

1. A display device, comprising:

at least one thin film transistor and at least one storage capacitor, both on a substrate, wherein

the at least one storage capacitor includes a storage electrode formed of a transparent oxide semiconductor, and a pixel electrode over the storage electrode, the pixel electrode being separated from the storage electrode by a desired distance,

the at least one film transistor includes a gate, a channel layer corresponding to the gate, and a gate insulating layer between the gate and the channel layer, the channel layer and the storage electrode being on a same surface of the gate insulating layer, and

the channel layer is formed of the transparent oxide semiconductor.

2. The display device of claim 1, wherein the transparent oxide semiconductor includes at least one oxide compound selected from the group consisting of zinc oxide, tin oxide, Ga-In-Zn oxide, In-Zn oxide, In-Sn oxide and combinations thereof.

3. The display device of claim 2, wherein the at least one oxide compound is doped with at least one metal selected from the group consisting of aluminum (Al), nickel (Ni), copper (Cu), tantalum (Ta), hafnium (Hf), titanium (Ti) and combinations thereof.

4. The display device of claim 1, wherein the pixel electrode is formed of a transparent conductive material selected from the group consisting of indium tin oxide (ITO), indium zinc oxide (IZO) and combinations thereof.

5. The display device of claim 1, wherein the thin film transistor further includes source and drain electrodes on opposing sides of the channel layer, and a passivation layer covering the source and drain electrodes.

6. The display device of claim 5, further comprising a storage electrode wiring electrically connected to the storage electrode, the storage electrode wiring and gate being on a same surface of the substrate.

7. The display device of claim 5, further comprising an etch stop layer covering the channel layer between the source and drain electrodes.

8. The display device of claim 7, wherein the etch stop layer is formed of a silicon oxide.

9. The display device of claim 5, wherein the passivation layer is between the storage electrode and the pixel electrode.

10. The display device of claim 5, wherein the gate insulating layer and the passivation layer are between the storage electrode and the pixel electrode.

11. The display device of claim 1, wherein the at least one thin film transistor includes a gate formed on the substrate, a gate insulating layer covering the gate, the channel layer corresponding to the gate and formed of the transparent oxide semiconductor, source and drain electrodes on opposing sides of the channel layer, and a passivation layer covering the source and drain electrodes;

and

the at least one storage capacitor includes a storage electrode wiring on the substrate, the gate insulating layer covering the storage electrode wiring, the storage electrode on the gate insulating layer, the passivation layer covering the storage electrode, and the pixel electrode on the passivation layer.

12. The display device of claim 11, wherein the storage electrode is on the gate insulating layer between the gate and the storage electrode wiring.

13. The display device of claim 11, wherein the pixel electrode is electrically connected to the drain electrode via the passivation layer.

14. The display device of claim 11, wherein the storage electrode is electrically connected to the storage electrode wiring via the passivation layer and the gate insulating layer.

15. The display device of claim 11, wherein the transparent oxide semiconductor includes at least one oxide compound selected from the group consisting of zinc oxide, tin oxide, Ga-In-Zn oxide, In-Zn oxide, In-Sn oxide and combinations thereof.

16. The display device of claim 15, wherein the least one oxide compound includes at least one metal selected from the group consisting of aluminum (Al), nickel (Ni), copper (Cu), tantalum (Ta), hafnium (Hf), titanium (Ti) and combinations thereof.

17. The display device of claim 11, further comprising an etch stop layer between the channel layer and the passivation layer, the channel layer being between the source and drain electrodes.

18. The display device of claim 17, wherein the etch stop layer is formed of a silicon oxide.

19. A display device, comprising:

at least one thin film transistor including a channel layer on a substrate and formed of a transparent oxide semiconductor, a gate insulating layer covering the channel layer, a gate on the gate insulating layer and corresponding to the channel layer, an interlayer dielectric layer covering the gate, source and drain electrodes on the interlayer dielectric layer electrically connected to opposing sides of the channel layer, and a passivation layer covering the interlayer dielectric layer and the source and drain electrodes, and

at least one storage capacitor including a storage electrode on the substrate and formed of the transparent oxide semiconductor, the gate insulating layer covering the storage electrode, a storage electrode wiring on and electrically connected to the gate insulating layer, the interlayer dielectric layer covering the storage electrode wiring, the passivation layer on the interlayer dielectric layer, and a pixel electrode on the passivation layer.

20. The display device of claim 19, wherein the storage electrode is on the substrate between the gate and the storage electrode wiring.

21. The display device of claim 19, wherein the transparent oxide semiconductor includes at least one oxide compound selected from the group consisting of zinc oxide, tin oxide, Ga-In-Zn oxide, In-Zn oxide, In-Sn oxide and combinations thereof.

22. The display device of claim 21, wherein the at least one oxide compound is doped with at least one metal selected from the group consisting of aluminum (Al), nickel (Ni), copper (Cu), tantalum (Ta), hafnium (Hf), titanium (Ti) and combinations thereof.