Interferometer having a dynamic beam steering assembly
US6252667A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 18, 1998 |
| Grant date | Jun 26, 2001 |
| Priority date | — |
| Expiry date | Sep 18, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01B2290/70
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
The invention features an interferometry system which includes at least one dynamic beam steering assembly for redirecting one or more beams within the interferometry system in response to changes in the angular orientation or position of the measurement object. A control circuit controls the beam steering assembly based on a signal derived from one or more beams within the interferometry system. For example, the control circuit can cause the beam steering assembly to redirect a measurement beam within the system such that exit measurement and reference beams used to generate an interferometric signal remain substantially parallel to one another over a range of angular orientations or translations of the measurement object. The interferometry systems can be advantageously incorporated into lithography systems used to fabricate integrated circuits and other semiconducting devices and beam writing systems used to fabricate lithography masks.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.