Low-Energy Ar+ Ion Induced Angularly Resolved AI(100) and AI(110) Sputtering Measurements

J. Vac. Sci. Tech., A17, 3443-3448 (1999).

Smith, P. C., Ruzic, D. N.

An apparatus and analysis method to obtain both the angular distribution of sputtered atoms and the total sputtering yield for materials of interest to physical vapor deposition (PVD) has been created. Total yield is determined by collecting the sputtered material on a quartz crystal oscillator (QCO) microbalance. The sputtered material is also collected on a pyrolytic graphite witness plate. By mapping the concentrations of the sputtered material on this plate, both polar and azimuthal angular distributions of the sputtered material can be determined. Utilizing this setup, data have been obtained for (200–500 eV) Ar ⁺ normally incident on polycrystalline aluminum sputtering targets with strong (100) and (110) crystallographic orientations. The overall yields of these samples compare well to the available data as well as empirical formulas. Crystallographic effects in the angular distributions are clearly seen. The Al(100) sample shows 12% enhanced sputtering along the 110 direction at all energies.