Photon Stimulated Desorption of Positive Ions from LiF

Abstract

Photon stimulated desorption (PSD) of positive ions from LiF is observed in the photon energy region between 30 and 70 eV. The creation of the Li + (1s→2s) core exciton leads to the rapid rise of both Li + and F + desorption yields. It is found that PSD of positive ions from LiF is due to the interatomic Auger transition. The yield spectrum of F + ions is different from that of Li + ions above 60 eV. The F + yield spectrum has a deep valley at around 63 eV, while the Li + spectrum shows a plateau in the same region. However the difference in the yield spectra of Li + and F + ions can not be explained at present.