Erosion behaviour and surface composition modifications of SiC under D+ ion bombardment

The erosion behaviour of fibre reinforced SiC under deuterium ion bombardment is investigated in the ion energy range between 20 eV and 1 keV. The sputtering yields are compared with earlier results obtained from SiC samples with different structure and fabrication. At D+ energies below 100 eV chemical erosion of C is found which results in a surface enrichment of Si. The surface composition modifications are investigated by Auger Electron Spectroscopy. The surface concentrations have been measured as a function of target temperature up to 1000 K. It is found that the Si surface enrichment reflects the ion energy and temperature dependence of the chemical erosion of C in SiC. At low D+ energies a Si rich thin altered layer covering the SiC target is formed. (orig.)