The sputtering rates of single‐crystal Si and polycrystalline Ag, Cu, Ni, Ti, and Al were measured. These target materials were bombarded with argon ions accelerated at 10 kV. The sputtered depth after a given interval of bombardment was greatest for Ag, and decreased for the other materials in the following order: Cu, Ni, Ti, Si, and Al. The difference in the sputtering rates of these target materials was investigated on the basis of their binding energies, and the following expression for sputtering rate was obtained experimentally,Sr=K(I/D)(M/Ec)k, whereSris the sputtering rate,Iis the current density of incident argon ions, andD,M, andEcare the atomic concentration, mass number, and cohesive energy of a target material, respectively.Kandkare constants. Sputtering yield (Sy) can be writtenSy=K′ (M/Ec)k. The result was compared with experimental data of many target materials already reported. These results were used to estimate the sputtered depth after a given interval in the practical analyses using ion bombardment.
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