Thermal Oxidation of Reactively Sputtered Titanium Nitride and Hafnium Nitride Films

Abstract
The oxidation behavior of reactively sputtered and thin films was investigated for oxide formation in dry and wet oxidizing ambient in the temperature range of 425°–800°C. For both cases, formation of a single‐oxide phase, rutile for oxidized and monoclinic for oxidized , was observed. The oxidation process is thermally activated, and it has a parabolic time dependence, except in the case of wet oxidized where nonuniform oxidation behavior was observed. The parabolic time dependence of the oxide growth is attributed to a transport‐controlled process which is limited by the diffusivity of the oxidant in the oxide. The dry oxidation of is much faster than the dry oxidation of at a given temperature. The oxidation rate is always higher in a wet than in a dry ambient.