Photoabsorption and MXCD in photoemission microscopy for characterisation of advanced materials

We applied chemical and magnetic sensitive photoemission electron microscopy (PEEM) to investigate surfaces of advanced materials. PEEM at low photon energies provides a high spatial resolution, but suffers from the lack of information about the chemical composition of the imaged surface. Such information can be obtained by PEEM via tuning the photon energy to X-ray absorption edges. To apply spectromicroscopy we acquired and subtracted microscopic images using photon energies just below and at the edges. The resulting difference gives a micro-image of the lateral distribution of a specific element. Microspectroscopy is performed by recording the intensity of secondary electrons in selected spots during a sweep of the photon energy. Additional information on the magnetic structure of the samples can be found by means of circularly polarised radiation making use of the magnetic dichroism MXCD. We applied these methods to micro-structered and nano-crystalline iron alloys using polarised soft X-ray radiation and a UV laser. (C) 1999 Elsevier Science B.V. All rights reserved.