In-plane switching mode liquid crystal display and method for fabricating the same

• US 9,030,637 B2
• Filed: 10/19/2012
• Issued: 05/12/2015
• Est. Priority Date: 10/17/2007
• Status: Active Grant

• Current Assignee: LG Display Co., Ltd.
• Original Assignee: LG Display Co., Ltd.
• Inventors: Oh, Jae-Young, Lee, Joon-Youp, Jin, Hyun-Cheol, Lee, Min-Jic
• Primary Examiner(s): Nguyen, Hoan C
• Application Number:
  US13/656,468
• Publication Number:
  US 20130040409A1
• Time in Patent Office: 935 Days
• Field of Search: 349 42- 43, 349/38, 349/39, 349/114
• 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]
• CPC Class Codes: G02F 1/136213 Storage capacitors associated with the pixel electrode

Abstract

A method for fabricating an in-plane switching (IPS) type liquid crystal display (LCD) device according to an embodiment includes forming gate lines arranged in a first direction and data lines arranged in a second direction substantially perpendicular to the first direction, the gate lines and the data lines defining pixel regions on an array substrate; forming a storage electrode on the array substrate; forming common electrodes extending across each pixel region; forming pixel electrodes arranged to be substantially parallel to the common electrodes, the common electrodes and the pixel electrodes being alternately arranged to generate an in-plane field in each pixel region; and forming thin film transistors (TFTs) at intersection areas of the gate lines and the data lines, each TFT including a source electrode connected to the corresponding data line, a drain electrode connected to the corresponding pixel electrode and a gate electrode.

Claims

1. A method for fabricating an in-plane switching (IPS) type liquid crystal display (LCD) device, comprising:

forming gate lines arranged in a first direction and data lines arranged in a second direction substantially perpendicular to the first direction, the gate lines and the data lines defining pixel regions on an array substrate;

forming a storage electrode on the array substrate;

forming common electrodes extending across each pixel region;

forming pixel electrodes arranged to be substantially parallel to the common electrodes, the common electrodes and the pixel electrodes being alternately arranged to generate an in-plane field in each pixel region;

forming thin film transistors (TFTs) at intersection areas of the gate lines and the data lines, each TFT including a source electrode connected to the corresponding data line, a drain electrode connected to the corresponding pixel electrode and a gate electrode; and

forming a common line under one of the common electrodes in the pixel region, the common line being substantially parallel to the data lines,

wherein the common line is underneath the respective common electrode to overlap the common electrode, and

wherein the common line and the data lines are formed on a first insulating layer on the array substrate with the gate electrode, the gate line and the storage electrode formed thereon.

2. The method of claim 1, wherein the gate lines, the storage electrode, and a gate pad line are formed by depositing a first conductive film on a surface of the array substrate and selectively patterning the first conductive film through a first photolithography process.

3. The method of claim 1, wherein the source and drain electrodes, the common line, the data line and a data pad line are formed by forming the first insulating layer, an amorphous silicon thin film, an n+ amorphous silicon thin film, and a second conductive film on a surface of the array substrate with the gate electrode, the gate line, the storage electrode and a gate pad line formed thereon, and then selectively removing the amorphous silicon thin film, the n+ amorphous silicon thin film, and the second conductive film through a second photolithography process.

4. The method of claim 1, wherein a plurality of contact holes exposing portions of the drain electrode, the storage electrode, the common line, a data pad line and a gate pad line are formed by forming a second insulating layer on a surface of the array substrate with an active pattern, the source and drain electrodes, the data line, a data pad line and the common line formed thereon, and then selectively removing the second insulating layer through a third photolithography process.

5. The method of claim 1, wherein the common electrodes, the pixel electrodes, a first and second connection lines, a data pad electrode and a gate pad electrode are formed on a second insulating layer by forming a third conductive film made of a transparent conductive film on a surface of the array substrate with first to fifth contact holes formed thereon, and then selectively removing the third conductive film through a fourth photolithography process.

6. The method of claim 1, wherein the common line traverses one of the gate lines.

7. The method of claim 1, wherein the common line and the common electrodes are made of a same transparent material.

8. A method for fabricating an in-plane switching (IPS) mode liquid crystal display (LCD) device, comprising:

forming a gate electrode and a gate line on a first substrate;

forming a first insulating layer on the first substrate;

forming an active pattern on the first substrate;

forming source and drain electrodes on the first substrate and forming an data line crossing the gate line to define a pixel area;

forming a storage electrode on the first substrate;

forming at least one common line in a direction substantially parallel to the data line within the pixel area of the first substrate;

forming a second insulating layer on the first substrate; and

forming a plurality of common electrodes and pixel electrodes alternately disposed within the pixel area of the first substrate to generate an in-plane field, such that at least one common electrode is positioned over an upper portion of the common line,

wherein the common line is underneath the respective common electrode to overlap the common electrode, and

wherein the common line and the data lines are formed on the first insulating layer on the first substrate with the gate electrode, the gate line and the storage electrode formed thereon.

9. The method of claim 8, further comprising:

forming a first connection line such that the first connection line is arranged to be substantially parallel to the gate line and connects one side of the common electrodes; and

forming a second connection line such that the second connection line is arranged to be substantially parallel to the gate line and connects one side of the pixel electrodes.

10. The method of claim 9, wherein the second connection line is electrically connected with the drain electrode via a first contact hole and electrically connected with the storage electrode via a second contact hole.

11. The method of claim 8, wherein the gate electrode, the gate line and the storage electrode are formed of a first conductive film, and wherein the source and drain electrodes, the data line and the common line are formed of a second conductive film.

12. The method of claim 8, wherein the storage electrode is formed at an edge of pixel area of the first substrate in a direction substantially parallel to the data line, and overlapping with the common electrode with the first and second insulating layers interposed therebetween to form a storage capacitor.

13. The method of claim 8, wherein the common line traverses the gate line.

14. The method of claim 8, wherein the common line and the common electrodes are made of a same transparent material.