Comment on “Sputtering transport theory: The mean energy”

A method to calculate the sputtering yield energy distribution based on the ion energy dependence of total sputtering yields is given and is used to show that the “cutoff” yield energy distribution published in Physical Review B in 1988 [G. Falcone, Phys. Rev. B 38, 6398 (1988)] is not tenable.

Figure 1

Ion-energy dependence of total sputtering yields of Cu bombarded at normal incidence with ${\mathrm{Ar}}^{+}$ ion. The experimental data have been taken from Falcone’s original paper (Ref. 2). The solid thin lines are theoretical curves: A stands for Sigmund sputtering yield $Y_0$, B stands for calculated results of Eq. (4) with $E_{\text{th}}=50\mathrm{eV}$. and C stands for calculated results of Eq. (2) with $E_{\text{th}}=60\mathrm{eV}$.

Figure 2

Normalized energy distribution of sputtered neutral Cu atom for bombarding ${\mathrm{Ar}}^{+}$ ion energies of 200 and $400\mathrm{eV}$. Small square $(E=200\mathrm{eV})$ and triangle $(E=400\mathrm{eV})$ stand for experimental measurement results (Ref. 4). The solid thin lines are theoretical curves: A stands for calculated results of Eq. (1) with $E=200$ and $400\mathrm{eV}$; B and C stand for calculated results of Eq. (3) with $E=400$ and $200\mathrm{eV}$, respectively.