Energy-tunable full-field x-ray microscopy: Cryo-tomography and nano-spectroscopy with the new BESSY TXM

We describe the new full-field transmission x-ray microscope (TXM) for automated cryo-tomography and nano-spectroscopy which is installed at the BESSY undulator U41. For the first time in soft x-ray microscopy, an elliptically shaped single-bounce glass capillary is employed as condenser which collects the divergent radiation emerging from the exit slit of a focusing spherical grating monochromator (FSGM). The new TXM overcomes several limitations of conventional TXM setups, it provides an energy resolution up to E/ΔE = 104 which is well suited for spectromicroscopy. Furthermore, no pinhole is required close to the sample plane which facilitates flat sample holder geometry for nano-tomography. With its high energy resolution, the TXM also supports imaging in high orders of diffraction of the zone plate objective. Using this approach, a spatial resolution of 14 nm lines and spaces is demonstrated. In addition, we present selected applications from materials and life sciences.