Alignment measurement system
US10942461B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 2, 2018 |
| Grant date | Mar 9, 2021 |
| Priority date | — |
| Expiry date | Jul 2, 2038 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F9/7084
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An apparatus for determining a characteristic of a feature of an object comprises: a measurement radiation source; a measurement radiation delivery system; a measurement system; a pump radiation source; and a pump radiation delivery system. The measurement radiation source is operable to produce measurement radiation and the measurement radiation delivery system is operable to irradiate at least a part of a top surface of the object with the measurement radiation. The measurement system is operable to receive at least a portion of the measurement radiation scattered from the top surface and is further operable to determine a characteristic of the feature of the object from at least a portion of the measurement radiation scattered from the top surface. The pump radiation source is operable to produce pump radiation and the pump radiation delivery system is operable to irradiate at least a part of the top surface of the object with the pump radiation so as to produce a mechanical response (for example an acoustic wave) in the object.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.