Method of and apparatus for automatic high-speed optical inspection of semi-conductor structures and the like through fluorescent photoresist inspection
US6091488A · kind A · utility
32Cited by
2References
20Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Mar 22, 1999 |
| Grant date | Jul 18, 2000 |
| Priority date | — |
| Expiry date | Mar 22, 2019 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N21/956
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Semiconductor wafers, circuit boards and similar multi-layer structures are optically inspected at high speeds with the aid of preferably a pair of oppositely and inclinedly directed laser beams at inclined angles to the vertical and the wafer surface to cause fluorescence by a photoresist layer carrying conductor patterns, defects in which are to be inspected, and using preferably a time-delay-integration CCD imaging camera for recording a fluorescent resist surface image accentuating the non-fluorescing conductor pattern thereupon, while masking all light from layers therebelow.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.