The sputtering of silicon dioxide (SiO2/Si) thin films deposited onto silicon substrates and irradiated by swift Auq+ heavy ions (q = +4 to +9) has been investigated both by experiment and via numerical modeling by varying the kinetic energy from 10 to 40 MeV. The induced sputtering yields were determined experimentally via the Rutherford backscattering spectrometry (RBS) technique using a 2‐MeV He+ ion beam. The obtained experimental results were first plotted versus the target electronic stopping power together with previous data available for the same projectile‐target system at high kinetic energies, indicating increased sputtering yields with increasing electronic energy loss. Then, the whole data were compared with numerical sputtering yield values derived both from the inelastic thermal spike model and the SRIM‐2013 simulation code by including, respectively, nonlinear elastic spikes and linear elastic collision cascades. A good agreement was observed between the measured sputtering yield data and i‐TS predicted values over higher incident energies used by using refined parameters of the ion slowing down with reduced thermophysical properties of the SiO2 thin film. Finally, the synergy between electronic and nuclear energy loss processes inducing sputtering at low incident energies was discussed through the comparison between experimental and numerical yield data.

We report here on the recently built Heavy Ion ERDA set up at iThemba LABS Gauteng; describing a typ-ical application in the study of interfacial reactions in an Al 2 O 3 -Ti ceramic-metal multilayer structure annealed in vacuum at 800 °C for 2 h. Depth profile extraction was found to be best obtained through combined use of direct calculation and Monte Carlo simulation codes as opposed to using just either of the methods. The obtained profile suggests a case of the Kirkendall effect, whereupon the inter-diffu-sion between the metal and the ceramic was largely due to the faster diffusion of the metal into the amor-phous ceramic than diffusion of the ceramic elements into the metallic layer.

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