Liquid crystal display device having contact structure and method of fabricating the same

• US 7,733,456 B2
• Filed: 04/28/2004
• Issued: 06/08/2010
• Est. Priority Date: 06/20/2003
• Status: Active Grant

• Current Assignee: LG Display Co., Ltd.
• Original Assignee: LG Display Co., Ltd.
• Inventors: Nam, Seung Hee, Oh, Jae Young, Lee, Kyoung Mook
• Primary Examiner(s): SCHECHTER, ANDREW M
• Application Number:
  US10/833,288
• Publication Number:
  US 20040257509A1
• Time in Patent Office: 2,232 Days
• Field of Search: 349/43, 349/139, 349/152
• US Class Current: 349/152
• CPC Class Codes: G02F 1/13452 Conductors connecting driver circuitry and terminals of panels
• CPC Class Codes: G02F 1/13458 Terminal pads
• CPC Class Codes: G02F 1/136227 Through-hole connection of the pixel electrode to the active element through an insulation layer
• CPC Class Codes: G02F 1/1368 in which the switching element is a three-electrode device G02F1/136277 takes precedence
• CPC Class Codes: H01L 2224/05553 being rectangular
• CPC Class Codes: H01L 24/06 of a plurality of bonding areas
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/12044 OLED
• CPC Class Codes: H01L 2924/14 Integrated circuits

Abstract

A liquid crystal display device includes a plurality of signal lines on a substrate, a plurality of pad electrodes on the substrate, each one of the plurality of pad electrodes connected to one of the plurality of signal lines, at least one insulating film on the plurality of pad electrodes, the at least one insulating film having a plurality of contact holes to expose portions of the pad electrodes, and a conductive film electrically connected to each of the plurality of pad electrodes through the contact holes.

Claims

1. A liquid crystal display device, comprising:

a plurality of signal lines including a date line, a gate line and a common line on a substrate;

a pixel electrode formed at an intersection area of the data line and the gate line;

a plurality of pad electrodes including a gate pad electrode, a data pad electrode and a common pad electrode on the substrate, each one of the plurality of pad electrodes connected to one of the plurality of signal lines;

two insulating films on the gate pad electrode and the common pad electrode, the two insulating films having a plurality of contact holes to expose a plurality of portions of each of the gate pad electrode and the common pad electrode; and

anisotropic conductive film of which a plurality of conductive particles are directly connected to each of the gate pad electrode and the common pad electrode through the contact holes without any intermediate layer there-between covering the contact holes and the gate and common pad electrodes,

wherein the pixel electrode and a common electrode is formed to generate a horizontal electric field in a pixel region defined by the intersection of the gate and data lines,

wherein each of the plurality of the contact holes has a depth larger than diameter of the conductive particles of the anisotropic conductive film,

wherein the data pad electrode include a semiconductor pattern having an active layer and an ohmic contact layer,

wherein each of the plurality of contact holes has a first U-shaped contact hole and a second U-shaped contact hole engaged with the first U-shaped contact hole along a widthwise direction of the pad electrodes.

2. The device according to claim 1, wherein the plurality of signal lines include:

the data line to which data signals are supplied via any one of the pad electrodes;

the gate line to which gate signals are supplied via any one of the pad electrodes; and

the common line to which a reference voltage signal is applied via any one of the pad electrodes.

3. The device according to claim 2, further comprising:

the common electrode formed in parallel to the pixel electrode at the intersection area,

wherein the pixel electrode receives the data signals and the common electrode receives the reference voltage signal to form the horizontal electric field parallel to the substrate.

4. The device according to claim 2, further comprising:

a transparent conductive film having a pattern similar to a pattern of the two insulating films.

5. The device according to claim 1, wherein each of the plurality of contact holes has a width of about 5 μ

m to about 50 μ

m.

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

forming a plurality of pad electrodes connected to a plurality of signal lines on a substrate;

forming two insulating films having a plurality of contact holes to expose a plurality of portions of each of the plurality of pad electrodes; and

connecting directly each of the exposed portions of the pad electrodes to a plurality of conductive particles of an anisotropic conductive film without any intermediate layer therebetween covering the contact holes and pad electrodes,

wherein each of the plurality of the contact holes has a depth larger than diameter of the conductive particles of the anisotropic conductive film,

wherein the data pad electrode include a semiconductor pattern having an active layer and an ohmic contact layer,

wherein each of the plurality of contact holes has a first U-shaped contact hole and a second U-shaped contact hole engaged with the first U-shaped contact hole along a widthwise direction of the pad electrodes.

7. The method according to claim 6, further comprising:

forming a data line to which data signals are supplied via any one of the pad electrodes; and

forming a gate line to which gate signals are supplied via any one of the pad electrodes.

8. The method according to claim 7, further comprising:

forming a pixel electrode at an intersection area of the data line and the gate line;

forming a transparent conductive film having a pattern similar to a pattern of the two insulating films.

9. The method according to claim 6, further comprising:

forming a common line to which a reference voltage signal is applied via any one of the pad electrodes and a common electrode connected to the common line; and

forming a pixel electrode receiving the data signals,

wherein the common electrode and the pixel electrode form a horizontal electric field parallel to the substrate.

10. The method according to claim 6, wherein each of the plurality of contact holes have a width of about 5 μ

m to about 50 μ

m.