Logo of the Physikalisch-Technische Bundesanstalt

Vacuum interferometer

PTBnews 3.2022
01.12.2022
Especially interesting for

semiconductor lithography

manufacturing of ultraprecise measuring machines and comparators

Laser interferometers are frequently used for high-precision length measurements on objects having structures in the nanometer range. If precision requirements are high, even slight changes of the refractive index of air have a negative impact. A measurement in vacuum would prevent this impact but is not possible for all measurement objects. Together with the Institut für Mikroelektronik- und Mechatronik-Systeme (IMMS) in Ilmenau, PTB has developed a principle that is based on an air-cushioned vacuum seal. The measurement object can be positioned outside the vacuum and – except for a very small air gap – the optical path of the interferometer runs within vacuum. (Technology Offer 420)

Advantages

interferometric measurement of objects that are not suitable for measurements in vacuum

high accuracy

position regulation free of vacuum forces

Contact person for questions about technology transfer

Andreas Barthel,
Telefon: (0531) 592-8307,
Opens local program for sending emailandreas.barthel(at)ptb.de,
Opens internal link in current windowwww.technologietransfer.ptb.de