The electronic energy loss of 100 keV heavy ions in medium energy ion scattering analysis of a Ta2O5 ultrathin film

Abstract

To optimize the depth resolution of Medium Energy Ion Scattering Spectroscopy (MEIS), a 10 nm Ta2O5 thin film on a Si(100) substrate was analyzed by MEIS using H+ and heavy ions such as Li+, N+ and Ne+ ions. The use of heavy ions such as Li+ and N+ increased the electronic stopping powers 2-3 times but it also increased the electronic straggling compared to H+ ions, For Nef ions, the ion neutralization problem was so severe that the scattering ion intensity from the subsurface layer was attenuated very rapidly and a strong doubly ionized Ne++ peak was observed. For 100 keV N+ and Ne+ ions, multiple scattering peaks were observed.