Method and apparatus for automated, in situ material detection using filtered fluoresced, reflected, or absorbed light
US6369887B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 25, 2001 |
| Grant date | Apr 9, 2002 |
| Priority date | — |
| Expiry date | Apr 25, 2021 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2021/6471
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method and apparatus for detection of a particular material, such as photo-resist material, on a sample surface. A narrow beam of light is projected onto the sample surface and the fluoresced and/or reflected light intensity at a particular wavelength band is measured by a light detector. The light intensity is converted to a numerical value and transmitted electronically to a logic circuit which determines the proper disposition of the sample. The logic circuit controls a sample-handling robotic device which sequentially transfers samples to and from a stage for testing and subsequent disposition. The method is particularly useful for detecting photo-resist material on the surface of a semiconductor wafer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.