A new empirical formula for the sputtering yield

Universal Energy Dependence of Sputtering Yields At Low Ion Energy

Sputtering yields Y(E)at ion energies E keV are shown to be described by the equation Y(E) = A(En - ) where A, n, and the threshold energy Eth are constants characteristic for a particular projectile/target combination. Examination of a wide variety of systems reveals that n = 0.5 provides an excellent universal representation of a large body of data, including physical sputtering of metals by noble gas ions, selfsputtering of metals, as well as physical and chemical sputtering of Si and SiO2. The above value for n is consistent with a 1/r4 power law atom-atom interaction potential within Sigmund's theory of sputtering. Another conclusion is that the effect of Eth on Y(E) must be taken into account at ion energies as high as 1 keV, not just near the sputtering threshold.