Speaker
Description
For the measurement of the spectral distribution in a broadband wavelength range, spectrographs are typically used. Depending on the target application, the spectrograph can be designed for reflection or transmission mode. Although reflective spectrographs generally offer a higher resolution due to the possibility of applying aberration corrections and focusing options, the main advantages of a transmission grating spectrograph are its compactness and the possibility of inline positioning while still offering sub-Ångström spectral resolution if designed carefully.
In this contribution the design, realization, and characterization of an EUV transmission grating spectrograph (EUV-TGS) are presented. The main module of the realized EUV-TGS comprises a spectral and spatial filter and a high-resolution transmission grating with a period of 80 nm. All components were fabricated in-house using multi-step cleanroom processes. For high resolution spectral monitoring in the target wavelength range of 10 nm to 20 nm, a two-dimensional detector is positioned in proximity to the main module. The overall dimensions of the EUV-TGS have been minimized to 25 x 25 x 40 mm³, allowing for simplified integration into existing beamlines and experimental setups. The realized prototype demonstrates a spectral resolution of 0.08 nm, perfectly suited for the detailed investigation of EUV radiation sources.
In our use case, the EUV-TGS prototype is integrated in an interference lithography setup for monitoring tasks, demonstrating that this ultra-compact spectrograph can easily be introduced into experimental setups that will benefit from an inline spectroscopic diagnostic option.
