System and method for improving TFT-array manufacturing yields

• US 7,024,338 B2
• Filed: 08/19/2003
• Issued: 04/04/2006
• Est. Priority Date: 01/31/2003
• Status: Expired due to Fees

• Current Assignee: Yieldboost Technologies Incorporated
• Original Assignee: Yieldboost Technologies Incorporated
• Inventors: Chung, Kyo Young
• Primary Examiner(s): Nghiem, Michael
• Assistant Examiner(s): LE, JOHN H
• Application Number:
  US10/642,617
• Publication Number:
  US 20040150408A1
• Time in Patent Office: 959 Days
• Field of Search: 702 81- 84, 702/183, 702/185, 700/97, 324/500, 324/512, 324/770, 324/537, 349/43
• US Class Current: 702/185
• CPC Class Codes: G05B 19/41875 characterised by quality surveillance of production
• CPC Class Codes: Y02P 90/02 Total factory control, e.g. smart factories, flexible manufacturing systems [FMS] or integrated manufacturing systems [IMS]

Abstract

A system and method for detecting defects in TFT-array panels is provided that improves defect detection accuracy by adjusting the thresholding parameters used to classify defective pixels when the number of defects reported by a TFT-array testing system exceeds a predetermined critical number. In a preferred embodiment, the thresholding parameters are adjusted until the number of reported defects is less than or equal to the predetermined critical number. The predetermined critical number represents a threshold number for determining if the number of reported defects is abnormally high. Reducing the number of reported defects to a number equal to or less than the predetermined critical number will decrease the operation time of the TFT-array repair equipment, because of the reduced number of potential defects it will be required to handle, and will also result in the TFT-array testing system reporting a smaller number of potential defects, with the potential defects that are reported having a higher probability of being real defects.

Claims

1. A method of improving defect detection accuracy of an electrode array testing system, wherein the electrode array defines a plurality of pixels and wherein the electrode array testing system determines if a pixel is defective based on at least one thresholding parameter that controls a pass/fail criteria of each pixel during testing of the TFT panel, comprising:

defining a critical number of defects;

comparing a number of defects reported by the electrode array testing system “

reported defects”

to the critical number of defects;

adjusting the at least one thresholding parameter if the number of reported defects is greater than the critical number of defects, until the number of reported defects is less than or equal to the critical number of defects, wherein the adjusting comprises,

incrementally adjusting the at least one thresholding parameter by a first increment value until the number of reported defects is less than the critical number of defects to yield a first thresholding parameter value,

subtracting one increment value from the first thresholding parameter value to yield a second thresholding parameter value, and

incrementally adjusting the second thresholding parameter value by a second increment value until the number of reported defects is less than the critical number of defects to yield a final thresholding parameter value,

wherein the second increment value is smaller than the first increment value.

2. The method of claim 1, wherein the at least one thresholding parameter is adjusted until the number of reported defects is less than or equal to the critical number of defects or until the at least one thresholding parameter reaches a predetermined maximum value.

3. The method of claim 1, wherein the critical number of defects corresponds to a number of defects over which the at least one thresholding parameter is adjusted to reduce the number of reported defects.

4. The method of claim 1, further comprising alerting a repair station and or cell and/or module inspection station if the number of reported defects has been reduced by adjusting the at least one thresholding parameter.

5. A computer-readable medium storing a program for improving defect detection accuracy of an electrode array testing system, wherein the electrode array defines a plurality of pixels and wherein the electrode array testing system determines if a pixel is defective based on at least one thresholding parameter that controls a pass/fail criteria of each pixel during testing of the TFT panel, said program comprising:

a first code section which compares a number of defects reported by the electrode array testing system “

reported defects”

to a predetermined critical number of defects;

a second code section which, if the number of reported defects is greater than the critical number of defects, adjusts the at least one thresholding parameter until the number of reported defects is less than or equal to the critical number of defects, wherein the second code section comprises;

a first code subsection that incrementally adjusts the at least one thresholding parameter by a first increment value until the number of reported defects is less than the critical number of defects to yield a first thresholding parameter value,

a second code subsection that subtracts one increment value from the first thresholding parameter value to yield a second thresholding parameter value, and

a third code subsection that incrementally adjusts the second thresholding parameter value by a second increment value until the number of reported defects is less than the critical number of defects to yield an final thresholding parameter value,

wherein the second increment value is smaller than the first increment value.

6. The computer-readable medium of claim 5, wherein the second code section adjusts the at least one thresholding parameter until the number of reported defects is less than or equal to the critical number of defects or until the at least one thresholding parameter reaches a predetermined maximum value.

7. The computer-readable medium of claim 5, wherein the critical number of defects corresponds to a number of defects over which the at least one thresholding parameter is adjusted to reduce the number of reported defects.

8. The computer-readable medium of claim 5, further comprising a third code section that alerts a repair station and/or cell and/or module inspection station if the number of reported defects has been reduced by adjusting the at least one thresholding parameter.