Contamination monitoring and control techniques for use with an optical metrology instrument
US7342235B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 16, 2006 |
| Grant date | Mar 11, 2008 |
| Priority date | — |
| Expiry date | Nov 16, 2026 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2021/157
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A technique is provided monitoring and removing contaminants from the surface of a sample that is being measured with an optical metrology tool. The monitoring and removing contaminants from the surface of a sample may occur prior to recording an optical response from said sample in order to ensure that accurate results are obtained. Contaminant layers may be quantified so that other measurements may be accurately obtained without requiring the removal of the contaminant layer. The contaminant layers may be removed through the exposure to optical radiation. Alternatively, properties of non-contaminant layers may be characterized by analyzing changes that occur in such layers by exposure to optical radiation. The optical metrology instrument may be an instrument which operates at wavelengths that include vacuum ultra-violet (VUV) wavelengths.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.