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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.

The sputtering of bismuth (Bi/Si) thin films deposited onto silicon substrates and irradiated by swift Cu q+ heavy ions (q = +4 to +7) was investigated by varying both the ion energy over the 10 to 26-MeV range and the ion fluence ϕ from 5.1 × 10 13 cm −2 to 3.4 × 10 15 cm −2 . The sputtering yields were determined experimentally via the Rutherford backscattering spectrometry technique using a 2-MeV He + ion beam. The measured sputtering yields versus Cu 7+ ion fluence for a fixed incident energy of 26 MeV exhibit a significant depression at very low ϕ-values flowed by a steady-state regime above~1.6 × 10 14 cm −2 , similarly to those previously pointed out for Bi thin films irradiated by MeV heavy ions. By fixing the incident ion fluence to a mean value of~2.6 × 10 15 cm −2 in the upper part of the yield saturation regime, the measured sputtering yield data versus ion energy were found to increase with increasing the electronic stopping power in the Bi target material. Their comparison to theoretical predicted models is discussed. A good agreement is observed between the measured sputtering yields and the predicted ones when considering the contribution of 2 competitive processes of nuclear and electronic energy losses via, respectively, the SRIM simulation code and the inelastic thermal spike model using refined parameters of the ion slowing down with reduced thermophysical proprieties of the Bi thin films. KEYWORDS electronic sputtering yield, nuclear and electronic stopping power, Rutherford backscattering spectrometry (RBS), inelastic thermal spike model, sss

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