Angular distribution of sputtered atoms from polycrystalline metal targets

摘要

Angular distribution of sputtered atoms from polycrystalline metal targets with crystallographic‐preferred orientation was measured for 0.5‐ and 1.0‐keV Ar+ions at incidence angles of 0° and 45°. The distribution was compared with that for a Si (100) single‐crystal target. Atoms sputtered from Au, Pt, Al, and NiFe targets are ejected preferentially in the directions of their close packing in the lattice. For the Si target, the distribution is under cosine. These results are explained in terms of the target‐surface crystal structure during and after ion bombardment. The surface structure for the metal targets remains essentially unchanged, but not for the Si target. Sputtered‐atom ejection along the target normally increases with increasing incident‐ion energy. Even at oblique incidence, heavy‐target atoms such as Au, appear to have preferentially ejected atoms in the close‐packed directions.