Array of active devices and method for testing an array of active devices

• US 7,098,987 B1
• Filed: 08/24/2005
• Issued: 08/29/2006
• Est. Priority Date: 08/24/2005
• Status: Active Grant

• Current Assignee: Nytell Software LLC (Intellectual Ventures LLC)
• Original Assignee: Chunghwa Picture Tubes Limited
• Inventors: Tung, Chun-Hung, Chang, Yuan-Hao, Jen, Chien-Chih, Shiau, Fu-Yuan
• Primary Examiner(s): Dudek, James A.
• Application Number:
  US11/161,952
• Time in Patent Office: 370 Days
• Field of Search: 349/43, 349/152, 349/192
• US Class Current: 349/152
• CPC Class Codes: G02F 1/1309 Repairing; Testing
• CPC Class Codes: G02F 1/133388 with constructional differences between the display region and the peripheral region
• CPC Class Codes: G02F 1/136254 Checking; Testing
• CPC Class Codes: H10K 59/131 Interconnections, e.g. wiring lines or terminals
• CPC Class Codes: H10K 59/88 Dummy elements, i.e. elements having non-functional features
• CPC Class Codes: H10K 71/70 Testing, e.g. accelerated lifetime tests

Abstract

An array of active devices and a method for testing an array of active devices are provided. The array comprises a substrate, a plurality of scan lines, a plurality of data lines, a plurality of pixel units and a plurality of test pads. The substrate comprises a display area and a peripheral area. The scan lines and the data lines are positioned on the substrate, and enclose a plurality of pixel areas and dummy pixel areas in the display area and the peripheral area, respectively. The pixel units are positioned in the pixel areas and are connected to the scan lines and the data lines, respectively. Finally, The test pads are positioned close to the scan lines and/or the data lines, and positioned on the substrate and in the peripheral area. Each of the test pads is connected to the corresponding data line or the corresponding scan line.

Claims

1. An array of active devices, comprising:

a substrate comprising a display area and a peripheral area;

a plurality of scan lines positioned on the substrate;

a plurality of data lines positioned on the substrate, wherein the data lines and the scan lines enclose a plurality of pixel areas in the display area and enclose a plurality of dummy pixel areas in the peripheral area;

a plurality of pixel units, positioned on the substrate and in the pixel areas, connected to the scan lines and the data lines, respectively; and

a plurality of first test pads, positioned in the dummy pixel areas, wherein each of the first test pads is connected to one of the data lines.

2. The array of active devices of claim 1, wherein each of the pixel units comprises:

a first active device connected to the corresponding scan line and the corresponding data line; and

a pixel electrode connected to the first active device.

3. The array of active devices of claim 2, wherein the pixel electrodes are formed of Indium Tin Oxide (ITO) or Indium Zinc Oxide (IZO).

4. The array of active devices of claim 1, wherein the first test pad are formed of Indium Tin Oxide (ITO) or Indium Zinc Oxide (IZO).

5. The array of active devices of claim 4, further comprising

a plurality of second active devices, positioned on the substrate and in the dummy pixel areas and electrically connected with the first test pads, wherein the second active devices are always turned on and each first test pad is connected to the corresponding data line through the corresponding second active device.

6. The array of active devices of claim 5, wherein the second active devices are thin film transistors, and the source terminal and the drain terminal of each of the thin film transistors are connected together.

7. The array of active devices of claim 1, wherein the first test pads are formed of metal.

8. The array of active devices of claim 7, further comprising a plurality of transparent electrodes, positioned in the dummy pixel areas between the pixel units and the first test pads, wherein each of the transparent electrodes electrically connects with the corresponding data line, and the transparent electrodes and the first test pads together serve as test pads.

9. The array of active devices of claim 1, further comprising a plurality of second test pads, positioned in the peripheral area and close to the scan lines, wherein each of the second test pads is connected to one of the scan lines.

10. The array of active devices of claim 9, wherein each of the pixel unit further comprises a storage capacitor, and the array of active devices further comprises a plurality of bus electrodes positioned in the peripheral area and electrically connected to the storage capacitors, wherein each second test pad is positioned between two of the bus electrodes.

11. The array of active devices of claim 9, further comprising a plurality of dummy pixel units positioned in the dummy pixel areas between the pixel units and the second test pads.