Additional real-time diagnostics on the EBL2 EUV exposure facility

The EUV BeamLine 2 (EBL2) is being used to expose samples to EUV radiation for optics and mask lifetime testing. Before and after exposure the samples can be analyzed in-situ by X-ray photoelectron spectroscopy (XPS). During exposure the samples can be monitored in real-time by an imaging ellipsometer. We report on the development of two additional real-time diagnostic systems that further extend the capabilities of the EBL2 system, a thermal imaging system and an EUV reflectometer. The thermal imaging system monitors the sample surface radiation during accelerated lifetime tests and the EUV reflectometer is able to monitor the sample reflectivity in real-time. These diagnostics systems will allow for a more efficient use of the EBL2 beam-time and therefore speed up the development of EUV optics suitable for high source power and high NA imaging.