6533b855fe1ef96bd12b0754

RESEARCH PRODUCT

Orbital mapping of carbon thin films by XANES-spectromicroscopy

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Abstract A laterally resolved micro-XANES study (X-ray absorption near edge structure) of amorphous carbon, hydrogen terminated CVD-diamond (100) and highly oriented pyrolytic graphite (HOPG) is presented. The results were obtained by means of a photoemission electron microscope. Using this technique the well-known spectral features of carbon in its different chemical states (sp 2 , sp 3 ) could be recorded. The sp 2 /sp 3 content of the films was extracted from the spectra. Images, taken at X-ray energies corresponding to maxima (π*, C–H*) of the unoccupied density of states in these spectra, map the lateral distribution of the different orbitals at the sample surface. This study revealed graphitic areas on a well-ordered diamond surface and shows the location of C–H bonds on edges of the basal plane of the HOPG. Profiting from the elemental selectivity of the method, even weak traces of iron contaminations are mapped at the diamond surface.