Electrode contact structure for a liquid crystal display device and manufacturing method thereof

• US 6,462,800 B1
• Filed: 06/29/2000
• Issued: 10/08/2002
• Est. Priority Date: 06/30/1999
• Status: Expired due to Term

• Current Assignee: BOE HYDIS Technology Company Limited (SK Hynix Inc.)
• Original Assignee: Hyundai Display Technology, Inc. (Hon Hai Precision Industry Co., Ltd.)
• Inventors: Lee, Seung Hee, Kim, Hyang Yul, Park, In Cheol
• Primary Examiner(s): Sikes, William L.
• Assistant Examiner(s): NGO, HUYEN LE
• Application Number:
  US09/607,576
• Time in Patent Office: 831 Days
• Field of Search: 349/141, 349/143, 349/43, 349/159
• US Class Current: 349/143
• 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 1/136227 Through-hole connection of the pixel electrode to the active element through an insulation layer

Abstract

A liquid crystal display device, and a manufacturing method thereof, having an existing box-like counter electrode connected to the source/drain electrode through a first contact hole in the gate insulating film and so is used as the pixel electrode, and the existing slit-shaped counter electrode is connected to the non-transparent metallic common bus line through a second contact hole in the gate insulating film and so becomes the counter electrode while maintaining the existing process layer structure as it is, so that even if a short circuit occurs between the gate bus line and the pixel electrode in the same layer due to the particle, degradation is limited to only one pixel, which results in enhancing of the process yield.

Claims

1. A liquid crystal display device comprising a plurality of unit pixels, each unit pixel comprising:

a pixel electrode formed on a lower substrate by patterning a first transparent electrode and including a protrusion at an end thereof so as to provide means for contact with one terminal of a thin film transistor;

a common bus line spaced at a predetermined distance from the pixel electrode;

a gate bus line formed on the opposite side of the common bus line with regard to the pixel electrode;

a gate insulating layer patterned to provide at least a first and a second contact holes;

a counter electrode formed over the pixel electrode by using a slit-shaped second transparent electrode, said second transparent electrode extending through the first contact hole so as to be connected to the common bus line; and

a data bus line intersecting with the gate bus line between two pixel electrodes in the adjacent unit pixel, the data bus line extending through the second contact hole so as to be connected to the pixel electrode at the protrusion end.

2. A device as claimed in claim 1, wherein the first contact hole has a size of 10×

30 μ

m.

3. A device as claimed in claim 1, wherein the second contact hole has a size of 6×

20 μ

m.

4. A device as claimed in claim 1, wherein the pixel electrode has a thickness of 400 Å

.

5. A device as claimed in claim 1, wherein the predetermined distance between the common bus line and the pixel electrode is 5 μ

m.

6. A device as claimed in claim 1, the data bus line comprises a laminate of molybdenum (Mo)/aluminum (Al)/molybdenum (Mo).

7. A method for manufacturing a liquid crystal display device, the method comprising the steps of:

forming a pixel electrode on a lower substrate by patterning a first transparent electrode, the pixel having a protrusion at an end thereof so as to provide contact with one terminal of a thin film transistor;

forming a common bus line spaced at a predetermined distance from the pixel electrode and then forming a gate bus line;

performing a vapor deposition of a gate insulating film on the gate bus line and then patterning the gate insulating film so as to provide first and second contact holes therein;

performing a vapor deposition of four layers on the gate bus line and then forming an etch stopper layer and an active layer by patterning;

forming a counter electrode over the pixel electrode by using a slit-shaped second transparent electrode and then providing extension of the counter electrode through the first contact hole in the gate insulating film to connect the counter electrode with the common bus line;

forming a data bus line that intersects with the gate bus line, forming a source/drain electrode and then providing extension of the source/drain electrode through the second contact hole in the gate insulating film to connect the source/drain electrode to the protruding end of the pixel electrode; and

coating a protective film on the resultant product and then opening the protective film by patterning for the preparation of a leader-bonding operation.