Examination of the sputtering profile of NiTi under target heating conditions

In this paper we have examined compositional shifts in NiTi film sputter-deposited from a heated and a cooled target. Substrates were radially placed at 18° intervals to capture the semicircular sputtering profile. The composition of the film was measured using Rutherford backscattering spectroscopy (RBS). Film thickness values were measured and the atomic flux captured was calculated. Results indicate that the target temperature significantly influences the composition of the sputtered film. It was found that, for cold targets, Ni and Ti sputter at different angles, producing a compositional shift in the film when compared with the target. For hot targets the sputtering angle is influenced to a lesser degree, such that the compositional shift is negligible. Therefore, target temperature appears to represent an approach to alter the stoichiometry of films deposited.