Unity yield conditions for sputtering of graphite by carbon ions

Selfsputtering yields for graphite have been investigated as function of ion energy, target temperature and angle of incidence. While the yield for normal incidence at room temperature never exceeds unity, both enhanced temperature and grazing angle of incidence can lead to a selfsputtering larger than one. Theoretical predictions of 100% ion reflection at angles of incidence above 850 could not be observed for energies smaller than 300 eV. The data are interpolated to construct regions of selfsputtering larger than unity in the energy versus angle-of-incidence space for temperatures up to 1900 K. (orig.)