Thin film thickness and optimal focus measuring using reflectivity
US5982496A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 11, 1996 |
| Grant date | Nov 9, 1999 |
| Priority date | — |
| Expiry date | Mar 11, 2016 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F7/09
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method and system for measuring the thickness of a patterned film. In one embodiment, a first patterned film is impinged with electromagnetic radiation having a wavelength which varies within a given wavelength range. The electromagnetic radiation reflected from the first patterned film is measured. The thickness of the first patterned film is then measured using thickness measuring equipment. The determined thickness of the first patterned film is then correlated with the measured reflectance of the electromagnetic radiation from the first patterned film. A second patterned film is then impinged with electromagnetic radiation having a wavelength which varies within the given wavelength range. The electromagnetic radiation reflected from the second patterned film is measured. The present invention uses the previously determined correlation to determine the thickness of the second patterned film.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.