Microscopy and microspectroscopy with soft X-rays

The availability of synchrotron radiation from undulators is the basis of a new probe of tunable X-rays. The realization of such a probe requires to produce a demagnified image of the monochromatized radiation from the source on the sample. For this purpose Fresnel zone plates, multilayer covered mirrors, and mirrors at grazing incidence are available. The probe sizes presently are between 30 nm and 1 μm.In the scanning microscope at HASYLAB/DESY in Hamburg a grazing incidence ellipsoid mirror is used to focus radiation in the energy range 15 eV to 1200 eV to a spot of 1 μm. In the VUV-region below 30 eV a normal incidence Schwarzschild objective allows a spatial resolution of 100 nm. The signals which are available for microscopy and microspectroscopy are transmission, photoelectrons, luminescence in the visible, UV and soft X-ray regions, scattered light and desorbed ions. Spectrometers for photoelectrons and visible/UV-luminescence are installed for secondary spectroscopy. Several of the signals are not only element specific but also specific to the chemical environment and binding character. Most of the techniques are very surface sensitive. Different projects are reviewed while we concentrated mainly on examples from our own station