Phase Formation and Optical Properties of Vanadium-Doped Aluminum Oxynitride

The phase formation, morphology, and optical properties of aluminum oxynitride (Al₅O₆N) doped with 0.01–5.0 at % of vanadium ions (relative to aluminum) have been studied. All samples fabricated by calcining mixtures of Al₂O₃, AlN, and V₂O₅ at 1750°C in a nitrogen flow are practically single-phase γ-AlON with minor impurities of aluminum nitride, as well as VC, VN, VO, or their solid solutions at a vanadium content of ≥0.1 at %. In AlON:V, the band gap E_g = 5.82–5.94 eV varies depending on the vanadium concentration. The luminescence of AlON:V is due to intrinsic defects and impurity luminescence centers. The presence of vanadium in AlON leads to an increase in the optical absorption and a decrease in the intensity of intrinsic luminescence because of the formation of vanadium-containing impurity phases.