Inspection method and apparatus, lithographic apparatus, lithographic processing cell, and device manufacturing method to measure a property of a substrate
US8115926B2 · kind B2 · utility
49Cited by
6References
25Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Oct 23, 2008 |
| Grant date | Feb 14, 2012 |
| Priority date | — |
| Expiry date | Aug 31, 2029 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F7/70616
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A system is configured to measure two separately polarized beams upon diffraction from a substrate in order to determine properties of the substrate. Circularly or elliptically polarized light sources are passed via a fixed phase retarder in order to change the phase of one of two orthogonally polarized radiation beams with respect to the two beams. The relative phases of the two radiation beams and other features of the beams are measured in a detector to provide information on the properties of the substrate surface.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.