Characterization and Oxidation Kinetics of Reactively Sputtered Ti1−xAlxN Film

Abstract

AbstractWe report on the use of Ti1−xAlxN as an electrically conductive barrier layer from the viewpoint of its oxidation kinetics and electrical properties. Auger electron spectroscopy depth profile analysis revealed the improvement of oxidation resistance with Al incorporation. At 650 °C, an oxygen diffusion coefficient and an activation energy of Ti0.47AI0.53N were determined to be 5.85×10−1 Å 2/sec and 2.51 eV respectively. Compared with TiN, this corresponds to an oxide gowth rate reduction of about two orders of magnitude. An Al-rich oxide layer, which gew near the Ti1−XAlxN surface, is believed to act as a passivation layer to oxidation. Furthermore, current-voltage characteristics showed that the oxidation resistant Ti1−xAlxN minimized the increase of electrical resistance after heat treatment in an oxidizing atmosphere. These results suggest that Ti1−xAlxN is an attractive candidate for an electrically conductive barrier layer for advanced memory device applications.