A reflectometer for at wavelength characterization of XUV reflection gratings

In our institute a technology centre for production and characterisation of highly efficient precision gratings is established. Within this project a new eflectometer for at wavelength characterisation of the fabricated blazed gratings has been developed and produced. This new chamber complements our SR based metrology instrumentation, namely the existing reflectometer [1] and the polarimeter ellipsometer chamber for polarisation studies on magnetic or non magnetic samples [2]. The main feature of the new reflectometer is the possibility to incorporate real gratings with dimensions up to 300 x 60 x 60 mm3 into the UHV chamber. The samples are adjustable within six degrees of freedom by a newly developed UHV tripod system, and the reflectivity can be measured between 0 and 90 degrees incidence angle for both s and p polarisation geometry. A variety of detectors will be accessable with a high dynamic range of at least 10 orders of magnitude. The reflectometer is coupled permanently to a new optics beamline [3] on a BESSY II bending magnet operating in the UV, EUV and soft x ray range with the polarisation adjustable to either linear or elliptical. It will be available by the end of 201