Liquid crystal display device and method of fabricating the same

• US 6,462,793 B1
• Filed: 10/30/2000
• Issued: 10/08/2002
• Est. Priority Date: 10/28/1999
• Status: Expired due to Term

• Current Assignee: LG Display Co., Ltd.
• Original Assignee: LG Philips LCD Company Limited (LG Display Co., Ltd.)
• Inventors: Park, Jae Deok, Ha, Yong Min
• Primary Examiner(s): Ullah, Akm E.
• Application Number:
  US09/698,156
• Time in Patent Office: 708 Days
• Field of Search: 349/42, 349/43, 349/39, 257/59, 257/72, 385/147
• US Class Current: 349/42
• CPC Class Codes: G02F 1/136204 Arrangements to prevent high voltage or static electricity failures
• CPC Class Codes: G02F 1/136286 Wiring, e.g. gate line, drain line

Abstract

A liquid crystal display device that is adapted to prevent a short defect between a gate metal film and a data metal film generated from an insulation breakage of an insulating film caused by a static electricity. In the device, a gate metal film is formed at the center of a semiconductor layer with being interleaved with a first insulating film. A connecting metal film is connected to the gate metal film and is formed at a substrate. A second insulating film covers the gate metal film and the connecting metal film and is provided with a first contact hole to expose a part of each side surface of the semiconductor layer and the center portion of the connecting metal film. A data metal film is provided on the second insulating film contacting the semiconductor layer by way of the first contact hole formed in each side surface of the semiconductor layer. A third insulating film covers the data metal film and the second insulating film and is provided with a second contact hole to expose a part of the data metal film and the center portion of the connecting metal film. A pixel electrode is provided on the third insulating film by way of the second contact hole. The connection parts exposed by the first and second contact holes are separated from each other.

Claims

1. A liquid crystal display device, comprising:

a semiconductor layer formed on a substrate;

a gate metal film formed at a center of the semiconductor layer, a first insulating film being formed between the semiconductor layer and the gate metal film, the gate metal film exposing two side surfaces of the semiconductor layer;

a connecting metal film connected to the gate metal film and formed on the substrate;

a second insulating film covering the gate metal film and the connecting metal film and provided with first contact holes to expose a part of each side surface of the semiconductor layer and the center portion of the connecting metal film;

a data metal film provided on the second insulating film contacting the semiconductor layer by way of the first contact holes formed to expose a portion of each side surface of the semiconductor layer;

a third insulating film covering the data metal film and the second insulating film and provided with a second contact hole to expose a part of the data metal film and the center portion of the connecting metal film; and

a pixel electrode provided on the third insulating film by way of the second contact hole,

said connection parts exposed by the first and second contact holes being separated from each other.

2. The liquid crystal display device according to claim 1, wherein the connecting metal film has a pattern width of less than 5 μ

m.

3. The liquid crystal display device according to claim 1, wherein the gate metal film and the data metal are made from the same metal material.

4. A method of fabricating a liquid crystal display device, comprising:

patterning a first metal film to form a gate metal film and a connecting metal film for connecting the gate metal film;

forming an insulating film to cover the gate metal film and the connecting metal film, and forming a first contact hole in the insulating film to expose at least one surface of the connecting metal film;

forming a second metal film on the insulating film provided with the first contact hole;

patterning the second metal film to provide a data metal film and, at the same time, to etch and primarily separate the connecting metal film by an etchant for the data metal film;

forming a protective insulating film on the data metal film;

forming a second contact hole on the protective insulating film to expose a partial surface of the data metal film and a separated area of the connecting metal film;

forming a third metal film on the protective insulating film provided with the second contact hole, and

patterning the third metal film to provide a pixel electrode connected to the data metal film and, at the same time, to secondarily separate the separated part of the connecting metal film by an etchant for the pixel electrode.

5. A method of fabricating a liquid crystal display device, comprising:

forming a semiconductor layer on a substrate;

disposing a first insulating film and a first metal film on the substrate provided with the semiconductor layer, and patterning the first insulating film and the first metal film into almost identical shapes to provide a connecting metal film for connecting the first metal film to the gate metal film in such a manner that at least part of the gate metal film is interleaved with the first insulating film to be overlapped with the center portion of the semiconductor layer;

doping each side surface of the semiconductor layer with impurity ions using the gate metal film and the connecting metal film as a mask;

forming a second insulating film on the substrate in which the semiconductor layer is doped with the impurity ions;

forming a first contact hole in the second insulating film to expose each side surface of the semiconductor layer doped with the impurity ions and a partial surface of the connecting metal film;

forming a second metal film on the substrate provided with the first contact hole and then etching the same to form a pattern of the data metal film contacting the semiconductor layer doped with the ions and, at the same time, etching the exposed part of the connecting metal film to separate the connecting metal film;

forming a third insulating film on the substrate in which the connecting metal film has been separated, and forming a second contact hole in the third insulating film at a part of the data metal film and the separated area of the connecting metal film; and

forming a third metal film on the third insulating film provided with the second contact hole and then etching the same to provide a pattern of the pixel electrode contacting a part of the data metal film, and making an additional etching of the separated connecting metal film.

6. The method according to claim 5, wherein the connecting metal film has a pattern width of less than 5 μ

m.

7. The method according to claim 5, wherein the gate metal film and the data metal are made from a same metal material.