Laser deposition of epitaxial titanium nitride films on (100) MgO

Abstract

We have investigated the formation of epitaxial (100) oriented TiN films grown on (100) MgO substrates using an excimer laser (wavelength 308 nm, pulse duration 45 ns, and energy density (5–6 J cm−2) physical vapor deposition method. The films were deposited by laser ablation of a TiN target pellet in high vacuum (∼3.0×10−7 Torr), with the substrate temperature ranging from 450 to 750 °C. The epitaxial films were obtained at relatively low substrate temperatures (∼450 °C). The deposited films were analyzed using cross-section and plan-view transmission electron microscopy, x-ray diffraction, Rutherford backscattering/channeling, Auger electron spectroscopy, and electron channeling patterns. The results indicate epitaxial film growth (〈100〉 TiN parallel to 〈100〉MgO) near the stoichiometric TiN composition, and low oxygen content. The minimum channeling yield χmin was found to be ≤10%. The room-temperature resistivity was as low as 50 μΩ cm and the lattice parameter was found to be 4.218 Å.