Thin film transistor array panel and method for repairing liquid crystal display including the same

• US 7,847,914 B2
• Filed: 11/09/2009
• Issued: 12/07/2010
• Est. Priority Date: 06/26/2003
• Status: Expired due to Term

• Current Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Kim, Dong-Gyu, Kim, Kyung-Wook
• Primary Examiner(s): Caley; Michael H
• Application Number:
  US12/615,220
• Publication Number:
  US 20100075562A1
• Time in Patent Office: 393 Days
• Field of Search: 349/39, 349/54, 349/55, 349/192
• US Class Current: 349/192
• CPC Class Codes: G02F 1/136213 Storage capacitors associated with the pixel electrode
• CPC Class Codes: G02F 1/136222 Colour filters incorporated in the active matrix substrate
• CPC Class Codes: G02F 1/136259 Repairing; Defects
• CPC Class Codes: G02F 1/136268 Switch defects

Abstract

A thin film transistor (TFT) array panel, a liquid crystal display (LCD), and a method of repairing a TFT array panel with a defective pixel is disclosed. When a white defect occurs such that a pixel is always in a white state, a corresponding pixel electrode is supplied with the predetermined voltage applied to a corresponding storage electrode line so that the pixel becomes permanently dark, which may not be easily detected. The connection between the pixel electrode and the storage electrode line is provided by illuminating a laser beam from a common electrode panel through a contact hole in the TFT array panel to electrically couple the storage electrode and the pixel electrode. Advantageously, a backlight unit or chassis does not need to be separated or disassembled from the LCD when repairing the defect. Furthermore, the color filter stripes and the light blocking member are not damaged, thereby improving the reliability of the repair.

Claims

1. A method for repairing a liquid crystal display (LCD) having a thin film transistor (TFT) array panel with a defective pixel, the TFT array panel including a storage electrode, an insulating layer over the storage electrode, a drain electrode of a transistor over the insulating layer, a color filter stripe over the drain electrode, and a pixel electrode over the color filter stripe, the pixel electrode being operably coupled to the drain electrode via an aperture through the color filter stripe, the method for repairing comprising:

providing a laser beam through the aperture until the pixel electrode is electrically coupled to the storage electrode; and

electrically isolating the drain electrode from the transistor.

2. The method of claim 1 wherein the laser beam is provided from a common electrode panel opposite the TFT array panel.

3. The method of claim 1, wherein the laser beam is directed through the pixel electrode, through the aperture, through the drain electrode, through the insulating layer, and to the storage electrode.

4. The method of claim 1, wherein the drain electrode is separated from the transistor by the laser beam.

5. The method of claim 1, wherein the pixel electrode is separated from the color filter stripe by a passivation layer having an aperture aligned with the aperture through the color filter stripe.

6. The method of claim 1, further comprising providing an ohmic contact between the drain electrode and the storage electrode.

7. The method of claim 1, further comprising providing a semiconductor stripe between the drain electrode and the storage electrode.