In-plane switching mode liquid crystal display device and fabrication method thereof

• US 20060203151A1
• Filed: 03/14/2006
• Published: 09/14/2006
• Est. Priority Date: 03/14/2005
• Status: Active Grant

• Current Assignee: LG Display Co., Ltd.
• Original Assignee: LG Philips LCD Company Limited (LG Display Co., Ltd.)
• Inventors: Kim, Dung-Guk
• Granted Patent: US 7,663,723 B2
• Time in Patent Office: Days
• US Class Current: 349/106
• CPC Class Codes: G02F 1/134363 for applying an electric field parallel to the substrate, i.e. in-plane switching [IPS]
• CPC Class Codes: G02F 1/136209 Light shielding layers, e.g. black matrix, incorporated in the active matrix substrate, e.g. structurally associated with the switching element
• CPC Class Codes: G02F 1/136222 Colour filters incorporated in the active matrix substrate
• CPC Class Codes: G02F 2201/40 Arrangements for improving the aperture ratio

Abstract

A liquid crystal display device includes a first substrate and a second substrate; a gate line and a data line on the first substrate crossing each other to define a pixel region; a switching element in the pixel region; a black matrix formed along the gate line and the data line on the first substrate, the black matrix having a portion that covers an upper side of the gate line and extends into the pixel region; a color filter located at the pixel region; a common electrode and a pixel electrode located on the color filter for generating an electric field within the pixel region; and a liquid crystal layer formed between the first and second substrates.

Claims

1. A liquid crystal display device comprising:

a first substrate and a second substrate;

a gate line and a data line on the first substrate crossing each other to define a pixel region;

a switching element in the pixel region;

a black matrix formed along the gate line and the data line on the first substrate, the black matrix having a portion that covers an upper side of the gate line and extends into the pixel region;

a color filter located at the pixel region;

a common electrode and a pixel electrode located on the color filter for generating an electric field within the pixel region; and

a liquid crystal layer formed between the first and second substrates.

2. The device of claim 1, wherein the common electrode and the pixel electrode are made of a transparent conductive material.

3. The device of claim 1, wherein the transparent conductive material is one of ITO (Indium Tin Oxide) and IZO (indium Zinc Oxide).

4. The device of claim 1, further comprising:

a passivation film formed on an entire surface of the first substrate and covering the data line.

5. The device of claim 4, wherein the black matrix and the color filer are formed above the passivation film.

6. The device of claim 1, further comprising:

a planarization film formed on an entire surface of the substrate and covering the black matrix and the color filter.

7. The device of claim 6, wherein the common electrode and the pixel electrode are formed above the planarization film.

8. The device of claim 7, wherein the common electrode and the pixel electrode are in contact with the planarization film.

9. The device of claim 1, wherein the common electrode and the pixel electrode are coplanar.

10. The device of claim 1, wherein the common electrode and the pixel electrode are above the black matrix.

11. The device of claim 1, further comprising a common line, the common line having a first portion covering the upper side of the gate line and a second portion covering an upper side of the data line, the common electrode extending from the first portion of the common line.

12. The device of claim 11, wherein the black matrix is below the common line.

13. The device of claim 12, wherein the black matrix is wider than the common line.

14. The device of claim 11, wherein the distance between the first portion of the common line and the pixel electrode is about 7 μ

m˜

9 μ

m.

15. The device of claim 11, wherein the black matrix extends into the pixel region to between the first portion of the common line and the pixel electrode.

16. The device of claim 1, further comprising:

a data signal cutoff line located in the pixel region and between the data line and the pixel electrode, the data signal cutoff line being parallel to the data line.

17. The device of claim 16, wherein the black matrix along the data line overlaps with a portion of the data signal cutoff line.

18. The device of claim 16, wherein the data signal cutoff line is in contact with the substrate.

19. The device of claim 16, wherein the data signal cutoff line is electrically connected with the common electrode.

20. The device of claim 1, wherein the liquid crystal display device is an in-plane switching mode liquid crystal display device, and the electric field is an in-plane electric field.

21. A method for fabricating a liquid crystal display device comprising:

provide a first substrate and a second substrate;

forming a gate line and a data line crossing each other on the first substrate to define a pixel region;

forming a black matrix along the gate line and the data line on the first substrate, the black matrix having a portion that covers an upper side of the gate line and extends into the pixel region;

forming a color filter at the pixel region; and

forming a pixel electrode and a common electrode on the first substrate for generating an electric field in the pixel region.

22. The method of claim 21, further comprising:

forming a data signal cutoff line in the pixel region and between the data line and the pixel electrode, the data signal cutoff line being parallel to the data line.

23. The method of claim 22, wherein the step of forming the black matrix includes forming the black matrix along the data line to overlap with a portion of the data signal cutoff line.

24. The method of claim 22, wherein the step of forming the data signal cutoff line includes forming the data signal cutoff line to be in contact with the substrate.

25. The method of claim 21, further comprising forming a common line, the common line having a first portion covering the upper side of the gate line and a second portion covering an upper side of the data line, the common electrode extending from the first portion of the common line.

26. The method of claim 25, wherein the step of forming the black matrix includes forming the black matrix to extend into the pixel region to between the first portion of the common line and the pixel electrode.

27. The method of claim 26, wherein the step of forming the black matrix includes forming the black matrix below the common line.

28. The method of claim 27, wherein the step of forming the black matrix includes forming the black matrix to be wider than the common line.

29. The method of claim 21, further comprising:

forming a passivation film on an entire surface of the first substrate and covering the data line.

30. The method of claim 29, wherein the steps of forming the black matrix and the color filer includes forming the black matrix and the color filer above the passivation film.

31. The method of claim 21, further comprising:

forming a planarization film on an entire surface of the substrate and covering the black matrix and the color filter.

32. The method of claim 31, wherein the steps of forming the common electrode and the pixel electrode includes forming the common electrode and the pixel electrode above the planarization film.

33. The method of claim 32, wherein the step of forming the common electrode and the pixel electrode includes forming the common electrode and the pixel electrode to be in contact with the planarization film.

34. The method of claim 21, wherein the step of forming the common electrode and the pixel electrode includes forming the common electrode and the pixel electrode to be coplanar.

35. The method of claim 21, wherein the step of forming the common electrode and the pixel electrode includes forming the common electrode and the pixel electrode above the black matrix.

36. The method of claim 21, wherein the liquid crystal display device is an in-plane switching mode liquid crystal display device, and the electric field is an in-plane electric field.