Optical measurement system using polarized light
US6515745B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 19, 2001 |
| Grant date | Feb 4, 2003 |
| Priority date | — |
| Expiry date | Oct 19, 2021 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N21/211
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An optical measurement system for evaluating the surface of a substrate or the thickness and optical characteristics of a thin film layer overlying the substrate includes a light source for generating a light beam, a static polarizing element for polarizing the light beam emanating from the light source, and a measurement system for measuring the light reflected from the substrate location. The measurement system includes a static beam splitting element for splitting the light reflected from the substrate into s-polarized light and p-polarized light. The measurement system further includes two optical sensors for separately measuring the amplitude of the s-polarized light and the intensity of the p-polarized light. A control system analyzes the measured amplitude of the s-polarized light and the p-polarized to determine changes in the topography of substrate or changes in the thickness or optical characteristics of the thin film layer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.