Liquid crystal display device with enhanced response speed, transmittance, and aperture ratio and method for manufacturing the same

• US 5,886,762 A
• Filed: 11/19/1997
• Issued: 03/23/1999
• Est. Priority Date: 11/29/1996
• Status: Expired due to Term

• Current Assignee: BOE HYDIS Technology Company Limited (SK Hynix Inc.)
• Original Assignee: Hyundai Electronics Industries Co. Ltd. (SK Hynix Inc.)
• Inventors: Lee, Seok-Lyul, Lee, Seung-Hee, Kim, Hyang-Yul, Kwon, Sun-Gil, Park, Hae-Sung, Rho, Bong-Gyu
• Primary Examiner(s): Sikes, William L.
• Assistant Examiner(s): CHOWDHURY, TARIFUR RASHID
• Application Number:
  US08/974,012
• Time in Patent Office: 489 Days
• Field of Search: 349/139, 349/141, 349/145, 349/146
• US Class Current: 349/141
• CPC Class Codes: G02F 1/134363 for applying an electric field parallel to the substrate, i.e. in-plane switching [IPS]

Abstract

Disclosed is a liquid crystal display device comprising gate line; a data line intersecting with the gate line over the gate line; a first electrode of transparent metal material comprising: a first portion elongated over the data line along the first direction and perpendicularly intersecting with the data line; a second portion comprising a plurality of branches each elongated along the second direction starting from the first portion of the first electrode toward the gate line; and a third portion separated by a predetermined distance along the second direction with the gate line, and elongated along the first direction starting from the longest branch to a space formed between the shortest branch and its closest branch; a second electrode of transparent metal material, formed on the same plane as the first electrode, the second electrode having a first portion corresponding to the second portion of the first electrode and a second portion corresponding to the third or first portion of the first electrode.

Claims

1. A liquid crystal display device comprising:

gate line elongated along a first direction;

a data line elongated along a second direction substantially perpendicular to said first direction, and intersecting with said gate line over said gate line;

a first electrode of transparent metal material and formed over said data line, comprising;

a first portion elongated over said data line along said first direction and perpendicularly intersecting with said data line;

a second portion comprising a plurality of branches each elongated along said second direction starting from said first portion of said first electrode toward said gate line, wherein one of two outer most branches is longer than branches between the two outer most branches, and the other outer most branch is shorter than branches between the two outer most branches; and

a third portion separated by a predetermined distance along said second direction with said gate line, and elongated along said first direction starting from said longest branch to a space formed between said shortest branch and its closest branch; and

a second electrode of transparent metal material, formed on the same plane as said first electrode, said second electrode comprising;

a first portion elongated along said first direction between said third portion of said first electrode and the end parts of said branches of said second portion of said first electrode from a portion corresponding to one end of the third portion of the first electrode to a portion corresponding to the other end of said third portion of said first electrode; and

a second portion comprising a plurality of branches each separated from said plurality of branches each of said first electrode by a predetermined distance, in which said second portion of second electrode is elongated along said second direction starting from said first portion of said second electrode to the space between said branches of said second portion of said first electrode.

2. The liquid crystal device as claimed in claim 1, wherein one of said first electrode and said second electrode is a counter electrode and the other is a pixel electrode.

3. The liquid crystal display device claimed in claim 1, wherein the width ratio of the branches of said first electrode and said second electrode is in the range of about 0.1 to 10.

4. The liquid crystal display device claimed in claim 1, wherein the width of both of the branches of said first electrode and said second electrode is in the range of about 4 to 8 μ

m.

5. The liquid crystal display device claimed in claim 1, wherein the ratio of the width of the branches of said second or first electrode and the distance between adjacent branches of said first or second electrode is in the range of about 0.1 to 2.

6. The liquid crystal display device claimed in claim 1, wherein said first and second Electrodes are of ITO.

7. The liquid crystal display device claimed in claim 1, further comprising a third electrode formed on the same plane as said gate line, elongated along said first direction so as to overlap with end parts of branches of said second electrode.

8. The liquid crystal display device claimed in claim 7, wherein said first electrode and said third electrode are connected by a contact.

9. The liquid crystal display device claimed in claim 8, wherein said first electrode arid said third electrode are a first counter electrode and a second counter electrode respectively, and said second electrode is a pixel electrode.

10. The liquid crystal display device claimed in claim 7, wherein said first electrode and said third electrode are a first counter electrode and a second counter electrode respectively, and said second electrode is a pixel electrode.

11. The liquid crystal display device claimed in claim 7, further comprising a substrate equipped with a black matrix facing the domain defined by said data line and said gate line, said domain excluding a space defined by said third electrode and said branches of said second electrode, said branches of said first electrode and said third portion of said first electrode.

12. The liquid crystal display device claimed in claim 1 further comprising a thin film transistor formed at a space between said shortest branch of said first electrode and said gate line.

13. The liquid crystal display device claimed in claim 12, wherein said thin film transistor is connected to said data line, said gate line, and said shortest branch of said first electrode.

14. The liquid crystal display device claimed in claim 13, wherein one of said first electrode and said second electrode is a counter electrode and the other is a pixel electrode.

15. a liquid crystal display device comprising:

a substrate;

a gate line formed on the top surface of said substrate, said gate line comprising a first portion elongated along a first direction, and a second portion protruded from said first portion by a predetermined length along a second direction which is perpendicular to said first direction;

a first electrode formed on the same plane as said gate line, separated along said second direction from said first portion of said gate line by a predetermined distance, elongated to said first direction;

a gate insulation film formed on the resulting structure on which said gate line and said first electrode are formed;

a semiconductor layer formed on top of said gate insulation film beneath which said second portion of said gate line is formed;

a data line comprising a first portion intersecting with said first portion of said gate line under said gate insulation film, and a second portion protracting from said first portion of said data line and overlapping with a predetermined part of one end of said semiconductor layer;

a second electrode where one end of said second electrode overlaps with a predetermined part of the other end of said semiconductor layer;

a protective layer formed on top of the resulting structure on which said data line and said first electrode are formed, equipped with contact holes that expose a predetermined part of said first electrode and a predetermined part of said second electrode;

a third electrode of a transparent metal material, formed on top of the resulting structure on said protective layer is formed, said third electrode comprising;

a first portion elongated along said first direction over said data line and perpendicularly intersecting with said first portion of said data line;

a second portion comprising a plurality of branches elongated along said second direction starting from said first portion of said third electrode toward said gate line, wherein one of the outer most branches is longer than the branches between the two outer most branches, and the other outer most branch is shorter than said branches between the two outer most branches; and

a third portion separated by a predetermined distance along said second direction with said gate line, and elongated along said first direction starting from said longest branch to the space formed between said shortest branch and its closest branch; and

a fourth electrode of a transparent metal material, formed on the same plane as said third electrode, said fourth electrode comprising;

a first portion elongated along said first direction between said third portion of said third electrode and the end part of said branches of said second portion of said third electrode from a portion corresponding to one end of said third portion of said third electrode to a portion corresponding to the other end of said third portion of said third electrode; and

a second portion comprising a plurality of branches each separated with said plurality of branches each of said third electrode by a predetermined distance, in which said branches each of second portion of said fourth electrode is elongated along said second direction starting from said first portion of said fourth electrode to the space between said branches of said second portion of said third electrode.

16. The liquid crystal display device claimed in claim 15, wherein said first and third electrodes are a first and second electrodes respectively, and said fourth electrode is a pixel electrode.

17. The liquid crystal display device claimed in claim 15, wherein said second electrode is a drain of a thin film transistor, said second portion of said gate line is a gate of said thin film transistor, said semiconductor layer is a channel of the same, and said second portion of said data line is a source of the same.

18. A method of manufacturing a liquid crystal display having a gate line elongated along a first direction and a data line elongated along a second direction practically perpendicular to the first direction and intersecting with the gate line, said method comprising the step of:

simultaneously forming a first electrode and a second electrode over said date line, said first electrode of transparent metal material comprising;

a first portion elongated over said data line along said first direction and perpendicularly intersecting with said data line;

a second portion comprising a plurality of branches each elongated along said second direction starting from said first portion of said first electrode toward said gate line, wherein one of the two outer most branches is longer than branches between the two outer most branches, and the other outer most branch is shorter than the branches between the two outermost branches; and

a third portion separated by a predetermined distance along said second direction with said gate line, and elongated along said first direction starting from said longest branch to the space formed between said shortest branch and its closet branch;

said second electrode of transparent metal material, formed on same plane as said first electrode, said second electrode comprising;

a first portion Elongated along said first direction between said third portion of said first electrode and the end part of said branches of said second portion of said first electrode from a portion corresponding to one end of the third portion of the first electrode to a portion corresponding to the other end of said third portion of said first electrode; and

a second portion comprising a plurality of branches each separated with said plurality of branches each of said first electrode by a predetermined distance, in which said second portion of said second electrode is elongated along said second direction starting from said first portion of said second electrode to the space between said branches of said second portion of said first electrode.

19. The method of manufacturing a liquid crystal device as claimed in claim 18, wherein one of said first electrode and said pixel electrode is a counter electrode and the other is a pixel electrode.

20. The method of manufacturing a liquid crystal device as claimed in claim 18, further comprising the step of forming a third electrode elongated along said first direction so as to overlap with end parts of branches of said second electrode, during said gate line formation.

21. The method of manufacturing a liquid crystal device as claimed in claim 18, after said step of manufacturing third electrode, further comprising the steps of:

successively forming a insulation layer and a protective layer on top of the resulting structure on which said third electrode formed is formed; and

etching a predetermined part of said insulation layer and protective layer to form contact holes so as to connect said first electrode and said third electrode.

22. The method of manufacturing a liquid crystal device as claimed in claim 18, wherein said first and said third electrode is a first and a second electrode respectively, and said second electrode is a pixel electrode.

23. The method of manufacturing a liquid crystal device as claimed in claim 18, wherein the ratio of the width of the branches of said first electrode and said second electrode is in the range of about 0.1 to 10.

24. The method of manufacturing a liquid crystal device as claimed in claim 18, wherein the width of the branches each of said first and second electrodes is in a range of about 4 to 8 μ

m.

25. The method of manufacturing a liquid crystal device as claimed in claim 18, wherein the ratio of the branch width of said second or said first electrode and the distance to their adjacent branch of first or second electrode is in a range of about 0.1 to 2.

26. The method of manufacturing a liquid crystal device as claimed in claim 18, wherein said first and second electrodes are of ITO.

27. A method of manufacturing a liquid crystal display device comprising the steps of:

providing a substrate;

forming simultaneously both a gate line and a first electrode on top surface of said substrate, said gate line comprising;

a first portion elongated along a first direction of said gate line, and a second portion protruded from said first portion by a predetermined length along a second direction which is perpendicular to said first direction, and

said first electrode being separated along said second direction from said first portion of said gate line of said gate line by a predetermined distance and elongated to said first direction;

forming a gate insulation film on the resulting structure on which said gate line and said first electrode are formed;

forming a semiconductor layer on top of a predetermined part of said gate insulation film where said second portion of said gate line is formed;

forming simultaneously a data line and a second electrode, said data line comprising;

a first portion intersecting with said first portion of said gate Line by way of said gate insulation film; and

a second portion protracting from said first portion of said data line and overlapping with a predetermined part of one end of said semiconductor layer, and

said second electrode where one of its end overlaps with a predetermined part of the other end of said semiconductor layer;

forming a protective film on the resulting structure on which said data line and second electrode are formed;

etching said protective film formed on said second electrode, and said protective film and said gate insulation layer formed on said first electrode to expose a predetermined part of said second electrode and a predetermined portion of said first electrode; and

forming simultaneously a third electrode and a fourth electrode, said third electrode of transparent metal material comprising;

a first portion elongated on said data line along said first direction and perpendicularly intersecting with said data line;

a second portion comprising a plurality of branches elongated along said second direction starting from said first portion of said third electrode toward said gate line, wherein one of the two outer most branches is longer than the branches in the two outer most branches, and the other outer most branch is shorter than the branches in the two outermost branches; and

a third portion separated by a predetermined distance along said second direction with said gate line and elongated along said first direction starting from said longest branch to the space formed between said shortest branch and its closest branch, and

said fourth electrode of transparent metal material, formed on the same plane as said third electrode, said fourth electrode comprising;

a first portion elongated along said first direction between said third portion of said third electrode and the end part of said branches of said second portion of said third electrode from a portion corresponding to one end of the third portion of said third electrode to a portion corresponding to the other end of said third portion of said third electrode; and

a second portion comprising a plurality of branches each separated with said plurality of branches each of said third electrode by a predetermined distance, in which said second portion of said fourth electrode is elongated along said second direction starting from said first portion of said fourth electrode to the space between said branches of said second portion of said third electrode.

28. The method of manufacturing a liquid crystal device as claimed in claim 27, wherein said first and third electrodes are first and second counter electrodes respectively, and said fourth electrode is a pixel electrode.

29. The method of manufacturing a liquid crystal device as claimed in claim 27, wherein said second electrode is a drain of a thin film transistor, said second portion of said gate line is a gate of said thin film transistor, said semiconductor layer is a channel of the same, and said second portion of said data line is a source of the same.

30. The method of manufacturing a liquid crystal device as claimed in claim 27, wherein said third and fourth electrodes are of ITO.

31. The method of manufacturing a liquid crystal device as claimed in claim 30, wherein said data line and said second electrode acre made of one selected from a group consisting of aluminum, titanium, tantalum, or chrome and combination thereof.

32. The method of manufacturing a liquid crystal device as claimed in claim 27, wherein sa d data line and said second electrode are made of one selected from a group consisting aluminum, titanium, tantalum, or chrome and combination thereof.

33. The method of manufacturing a liquid crystal device as claimed in claim 27, wherein said gate insulation film is formed by oxidizing the metal used to form said data line and said second electrode.