Liquid crystal display device and method of fabricating same

• US 20090290084A1
• Filed: 07/28/2009
• Published: 11/26/2009
• Est. Priority Date: 06/05/2004
• Status: Active Grant

• Current Assignee: LG Philips LCD Company Limited (LG Display Co., Ltd.)
• Original Assignee: LG Philips LCD Company Limited (LG Display Co., Ltd.)
• Inventors: Ahn, Byung Chul, Lee, Ji No, Kwack, Hee Young, Jung, Tae Yong
• Granted Patent: US 7,817,231 B2
• Time in Patent Office: Days
• US Class Current: 349/46
• CPC Class Codes: G02F 1/133555 Transflectors
• CPC Class Codes: G02F 1/1362 Active matrix addressed cells G02F1/134336, G02F1/134363 take precedence
• CPC Class Codes: G02F 1/136231 for reducing the number of lithographic steps

Abstract

A liquid crystal display device is provided that comprises a gate line; a first insulating film on the gate line; a data line crossing the gate line to define a pixel region, the pixel region having a transmissive area and a reflective area; a thin film transistor connected to the gate line and the data line; a pixel electrode formed in the pixel region; a second insulating film on the thin film transistor; a storage capacitor including a storage upper electrode overlapping the gate line; a transmission hole exposing at least a portion of the pixel electrode, and a reflective electrode formed in the reflective area of the pixel region, the reflective electrode connecting the pixel electrode with thin film transistor and the storage upper electrode, wherein the gate line and the pixel electrode include a first transparent conductive layer.

Claims

1. A liquid crystal display device, comprising:

a gate line including a first transparent conductive layer;

a first insulating film on the gate line;

a data line crossing the gate line to define a pixel region, the pixel region having a transmissive area and a reflective area;

a first thin film transistor connected to the gate line and the data line;

a pixel electrode having a first transparent conductive layer;

a storage capacitor including a storage upper electrode overlapping the gate line;

a transmission hole exposing at least a portion of the first transparent conductive layer of the pixel electrode; and

a reflective electrode formed in the reflective area of the pixel region, wherein the reflective electrode is directly connected with the pixel electrode, a drain electrode of the first thin film transistor and the storage upper electrode within the transmission hole.

2. The device according to claim 1, further comprising a second conductive layer on the first transparent conductive layer of the gate line.

3. The device according to claim 1, further comprising a second conductive layer on the boundary of the first transparent conductive layer of the pixel electrode.

4. The device according to claim 2, further comprising:

a double layered gate pad extending from the gate line, wherein a portion of a first conductive layer of the double layered gate pad is exposed via a first contact hole by passing through the first insulating film and a second conductive layer of the double layered gate pad.

5. The device according to claim 4, further comprising:

a double layered data pad connected to the data line, wherein a portion of a first conductive layer of the double layered data pad is exposed via a second contact hole by passing through the gate insulating film and a second conductive layer of the double layered data pad.

6. The device according to claim 5, further comprising a second insulating film on the first thin film transistor.

7. The device according to claim 6, wherein the second insulating film is removed in the gate and data pads.

8. The device according to claim 6, further comprising a third insulating film between the first thin film transistor and the second insulating film.

9. The device according to claim 8, wherein the third insulating film is an inorganic insulating material.

10. The device according to claim 6, further comprising a third insulating film between the second insulating film and the reflective electrode.

11. The device according to claim 10, wherein the third insulating film is an inorganic insulating material.

12. The device according to claim 3, wherein the reflective electrode is directly connected to the first transparent conductive layer of the pixel electrode and substantially laterally connected to the second conductive layer of the pixel electrode through the transmission hole.

13. The device according to claim 5, further comprising:

a double layered data link extending from the data pad; and

a first contact electrode of the same metal as the reflective electrode connecting the data line and the data line through third and fourth contact holes exposing the data line and the data link.

14. The device according to claim 13, further comprising an electrostatic discharging device connected to one of the data and gate lines.

15. The device according to claim 14, wherein the electrostatic discharging device comprises:

a second thin film transistor connected to one of the gate and data lines;

a third thin film transistor connected between a gate electrode and a source electrode of the second thin film transistor in a diode form;

a fourth thin film transistor connected between the gate electrode and a drain electrode of the second thin film transistor in a diode form;

a second contact electrode connected to a source electrode and a gate electrode of the third thin film transistor through a fifth contact hole and a sixth contact hole exposing the source and gate electrodes;

a third contact electrode connected to a drain electrode of the third or fourth thin film transistor and the gate electrode of the second thin film transistor through a seventh contact hole and a eighth contact hole exposing the drain and gate electrodes; and

a fourth contact electrode connected to a source electrode and a gate electrode of the fourth thin film transistor through a ninth contact hole and a tenth contact hole exposing the source and gate electrodes of the fourth thin film transistor.

16. The device according to claim 15, wherein the second, third and fourth contact electrodes are formed of the same metal as the reflective electrode.

17. The device according to claim 15, wherein the gate electrodes have a double layered structure.

18. The device according to claim 17, wherein the fourth, sixth, eighth, tenth contact holes expose a first conductive layer of the double layered structure electrodes by passing through a second conductive layer of the gate electrodes.

19. The device according to claim 15, wherein the first to fourth contact electrodes are formed inner portion from a sealant region.

20. The device according to claim 15, wherein the reflective electrode and the first to fourth contact electrodes are formed of AlNd and Mo.

21. The device according to claim 6, wherein the insulating film has an embossed surface.

22. The device according to claim 21, wherein the reflective electrode has an embossed surface in a reflective area.

23. The device according to claim 6, wherein the second insulating film is an organic material.

24. The device according to claim 1, wherein the storage upper electrode substantially overlaps more than half of the gate line in the direction of the data line.

25. The device according to claim 1, wherein the reflective electrode connects the pixel electrode with the thin film transistor and the storage upper electrode through the transmission hole.