Liquid crystal display device and method of manufacturing the same

• US 8,743,306 B2
• Filed: 07/08/2011
• Issued: 06/03/2014
• Est. Priority Date: 11/17/2010
• Status: Active Grant

• Current Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Original Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Inventors: Kim, Yong Joo, Nam, Doo In, Shim, Jang Yeop, Kwak, Kyung Gook, Lee, Seung Kyu
• Primary Examiner(s): Doan, Jennifer
• Application Number:
  US13/178,910
• Publication Number:
  US 20120120358A1
• Time in Patent Office: 1,061 Days
• Field of Search: 349/33, 349/38, 349/39, 349/54
• US Class Current: 349/39
• CPC Class Codes: G02F 1/1345 Conductors connecting electrodes to cell terminals
• CPC Class Codes: G02F 1/136213 Storage capacitors associated with the pixel electrode
• CPC Class Codes: G02F 1/136286 Wiring, e.g. gate line, drain line

Abstract

A liquid crystal display device and a method of manufacturing the same. The liquid crystal display device includes a plurality of pixel cells on a substrate and a common voltage line. The common voltage line provides a common voltage to the pixel cells, and includes first to third interconnection patterns which are sequentially stacked over the substrate. Each of the pixel cells includes a storage capacitor which includes a lower electrode, and an upper electrode over the lower electrode. The second interconnection pattern includes the same material as a material of the upper electrode, and is formed in the same process as a process of the upper electrode.

Claims

1. A liquid crystal display device comprising:

a plurality of pixel cells on a substrate; and

a common voltage line providing a common voltage to the pixel cells, the common voltage line comprising first, second and third interconnection patterns which are sequentially stacked over the substrate, wherein;

each of the pixel cells comprises a storage capacitor comprised of a lower electrode, and an upper electrode over the lower electrode, and

the second interconnection pattern comprises the same material as a material of the upper electrode, and the second interconnection pattern is formed in the same process as a process of forming the upper electrode.

2. The liquid crystal display device of claim 1, wherein the second interconnection pattern is disposed at the same level as a level of the upper electrode.

3. The liquid crystal display device of claim 1, wherein:

each pixel cell further comprises a transistor,

the transistor comprises a semiconductor pattern on the substrate, a gate electrode overlapping with the semiconductor pattern, a gate dielectric between the semiconductor pattern and the gate electrode, and a source electrode and a drain electrode which contact the semiconductor pattern of both sides of the gate electrode, and

the first interconnection pattern comprises the same material as a material of the gate electrode, and is formed in the same process as a process of forming the gate electrode.

4. The liquid crystal display device of claim 3, wherein the first interconnection pattern and the gate electrode are disposed at different levels.

5. The liquid crystal display device of claim 3, wherein the first interconnection pattern and the gate electrode are disposed at the same level.

6. The liquid crystal display device of claim 3, wherein the third interconnection pattern, the source electrode and the drain electrode are formed in the same process as a process of forming the third interconnection pattern.

7. The liquid crystal display device of claim 1, wherein the first interconnection pattern comprises the same material as a material of the lower electrode, and is formed in the same process as a process of forming the lower electrode.

8. The liquid crystal display device of claim 1, wherein the first interconnection pattern and the lower electrode are disposed at the same level.

9. The liquid crystal display device of claim 1, wherein:

the second and third interconnection patterns are directly contacted, and

the liquid crystal display device further comprises a dielectric layer between the first and second interconnection patterns.

10. The liquid crystal display device of claim 9, wherein the common voltage line further comprises a contact plug which connects the first and second interconnection patterns through the dielectric layer and the second interconnection pattern.

11. The liquid crystal display device of claim 1, wherein:

the first and second interconnection patterns comprise the same material, and

the first and second interconnection patterns comprise a different material from a material of the third interconnection pattern.

12. The liquid crystal display device of claim 1, wherein the common voltage line is disposed on an edge portion of the substrate and surrounds the pixel cells.