Method to accurately determine classification codes for defects during semiconductor manufacturing

• US 6,185,511 B1
• Filed: 11/28/1997
• Issued: 02/06/2001
• Est. Priority Date: 11/28/1997
• Status: Expired due to Term

• Current Assignee: Advanced Micro Devices, Inc.
• Original Assignee: Advanced Micro Devices, Inc.
• Inventors: Steffan, Paul J., Chen, Ming Chun
• Primary Examiner(s): WACHSMAN, HAL D
• Application Number:
  US08/979,629
• Time in Patent Office: 1,166 Days
• Field of Search: 702/81-84, 702/33-36, 702/40, 702/108, 702/113-115, 702/117-123, 702/179, 702/180, 702/159, 702/172, 702/183-185, 702/FOR.155, 702/FOR.139, 702/FOR-135, 702/FOR-123, 702/FOR.170, 702/FOR.171, 700/109, 700/110, 700/115-121, 438/10-12, 438/14-18, 382/149, 382/141, 382/144, 382/145, 382/152, 382/224, 348/125, 348/126, 348/129, 348/130, 356/237.2, 356/237.4, 324/537, 324/764-769, 209/571-573
• US Class Current: 702/81
• CPC Class Codes: G06F 18/00 Pattern recognition
• CPC Class Codes: G06T 2207/30148 Semiconductor; IC; Wafer
• CPC Class Codes: G06T 7/0004 Industrial image inspection
• CPC Class Codes: H01L 22/20 Sequence of activities consisting of a plurality of measurements, corrections, marking or sorting steps

Abstract

A method of determining classification codes for defects occurring in semiconductor processes comparing images of defects from a first selected wafer with images of defects in a first image reference library. The images in the first image reference library are updated from a master image reference library. The images in the master image reference library are the best images of defect types. The images in the master image reference library are in a format readable by all review stations utilized to review the images of the defect.

Claims

1. A method of determining classification codes for defects occurring in semiconductor manufacturing processes, the method comprising:

sending a production lot of wafers through a first manufacturing process;

scanning a selected wafer from the production lot in a first inspection tool to identify defects on the selected wafer;

selecting defects from the identified defects on the selected wafer to review;

forming images of the selected defects on the selected wafer;

comparing the images of the selected defects on the selected wafer with defect images formed of defects previously identified in the first inspection tool and stored in a first image reference library; and

determining a classification code for each selected defect on the selected wafer based upon the comparison of the images of the selected defects on the selected wafer with the defect images stored in the first image reference library.

2. The method of claim 1 further comprising:

sending the images of the selected defects on the selected wafer to a master image reference library; and

updating the defect images stored in the first image reference library from the master image reference library, wherein the classification code for each selected defect is inspection tool independent.

3. The method of claim 2 further comprising:

scanning at least a second selected wafer from the production lot of wafers in a second inspection tool to identify defects on the at least a second selected wafer;

selecting defects from the identified defects on the at least a second selected wafer to review;

forming images of the selected defects on the at least a second selected wafer;

comparing the images of the selected defects on the at least a second selected wafer with defect images formed of defects previously identified in the second inspection tool and stored in a second image reference library;

determining a classification code for each selected defect on the at least a second selected wafer based upon the comparison of the images of the selected defects on the at least a second selected wafer with the defect images stored in the second image reference library.

4. The method of claim 3 further comprising:

sending the images of the selected defects on the at least a second selected wafer to the master image reference library; and

updating the defect images stored in the second image reference library, wherein the classification code for each selected defect is inspection tool independent.