Positron annihilation spectroscopy of the defect structure of sputter-deposited TiN

Abstract

Doppler and slow positron annihilation spectroscopy (PAS) techniques were used to investigate defect structures, as a function of composition and deposition sputtering power, in TiNx (0.48 ⩽ x ⩽ 1.11) thin films fabricated by physical vapor deposition methods. The recovery of the defect structures during a 1 h anneal at 900 °C was also studied. The present data, together with previous positron lifetime data (for the same samples), indicate that PAS has the potential to become an extremely useful technique for the characterization of atomic-scale defects in these materials. The conventional bulk PAS techniques yield consistent data if the results are corrected for the substrate contribution to the measured S parameters and the films have thicknesses greater than a few microns. For films with thicknesses on the order of 1 – 2 μm the slow PAS technique must be used.