Liquid crystal display device and fabricating method thereof

• US 20070205422A1
• Filed: 04/23/2007
• Published: 09/06/2007
• Est. Priority Date: 12/24/2004
• Status: Active Grant

• Current Assignee: LG Display Co., Ltd.
• Original Assignee: LG Display Co., Ltd.
• Inventors: Ahn, Byung, Park, Byung, Lim, Joo
• Granted Patent: US 7,626,206 B2
• Time in Patent Office: Days
• US Class Current: 257/83
• CPC Class Codes: H01L 27/12 the substrate being other than a semiconductor body, e.g. an insulating body
• CPC Class Codes: H01L 27/124 with a particular composition, shape or layout of the wiring layers specially adapted to the circuit arrangement, e.g. scanning lines in LCD pixel circuits wiring structures per se H01L23/52
• CPC Class Codes: H01L 27/1288 employing particular masking sequences or specially adapted masks, e.g. half-tone mask
• CPC Class Codes: H01L 29/41733 for thin film transistors with insulated gate
• CPC Class Codes: H01L 29/458 for thin film silicon, e.g. source or drain electrode
• CPC Class Codes: H01L 29/4908 for thin film semiconductor, e.g. gate of TFT
• CPC Class Codes: Y10S 438/951 Lift-off

Abstract

A thin film transistor substrate and a fabricating method thereof for simplifying a process are disclosed. In a liquid crystal display device according to the present invention, a gate line is provided on a substrate. A data line crosses the gate line with having a gate insulating film therebetween to define a pixel area. A thin film transistor includes a gate electrode connected to the gate line, a source electrode connected to the data line, a drain electrode opposed to the source electrode and a semiconductor layer for defining a channel between the source electrode and the drain electrode. A pixel electrode is connected to the drain electrode and is provided at said pixel area. Herein, said data line, said source electrode and said drain electrode have a double-layer structure in which a source/drain metal pattern and a transparent conductive pattern are built. Said pixel electrode is formed by an extension of the transparent conductive pattern of the drain electrode. A protective film makes a border with the transparent conductive pattern and provided at the remaining area thereof.

Claims

1. A liquid crystal display device, comprising:

a gate line provided on a substrate;

a data line crossing the gate line with having a gate insulating film therebetween to define a pixel area;

a thin film transistor including a gate electrode connected to the gate line, a source electrode connected to the data line, a drain electrode opposed to the source electrode and a semiconductor layer for defining a channel between the source electrode and the drain electrode; and

a pixel electrode connected to the drain electrode and provided at said pixel area,

wherein said data line, said source electrode and said drain electrode have a double-layer structure in which a source/drain metal pattern and a transparent conductive pattern are built; and

said pixel electrode is formed by an extension of the transparent conductive pattern of the drain electrode, and

further comprising;

a protective film making an interface with the transparent conductive pattern and provided at the remaining area thereof.

2. The liquid crystal display device as claimed in claim 1, further comprising:

a storage capacitor provided such that the pixel electrode overlaps with the gate line with having the gate insulating film therebetween.

3. The liquid crystal display device as claimed in claim 1, wherein the gate line and the gate electrode have a multiple-layer structure in which at least two metal layers are built on the substrate.

4. The liquid crystal display device as claimed in claim 1, further comprising:

a pad connected to each of the gate line and the data line,

wherein said pad includes;

a lower pad electrode provided on the substrate along with the gate line;

a contact hole passing through the gate insulating film to expose the lower pad electrode; and

an upper pad electrode connected, via said contact hole, to the lower data pad electrode and formed from said transparent conductive pattern.

5. The liquid crystal display device as claimed in claim 4, further comprising:

a data link provided in such a manner to be extended from the lower pad electrode included in the data pad;

a second contact hole passing through the gate insulating film to expose the data link; and

a contact electrode extended from the transparent conductive pattern of the data line to be connected, via said second contact hole, to the data link.

6. The liquid crystal display device as claimed in claim 5, wherein the contact electrode is integral to the upper pad electrode included in the data pad.

7. The liquid crystal display device as claimed in claim 5, wherein the transparent conductive pattern is provided in such a manner to capture the source/drain metal pattern.

8. The liquid crystal display device as claimed in claim 5, wherein the upper pad electrode and the contact electrode make an interface with the protective film.

9-20. -20. (canceled)