Preparation of molybdenum oxide thin films by MOCVD

In this study, molybdenum oxide films were prepared in a horizontal hot-wall MOCVD apparatus using molybdenum dioxide acetylacetonate as precursor. The molybdenum precursor was synthesized from acetylacetone and molybdenum oxide powder. Thermal gravimetric (TG) and differential thermal analyses (DTA) of the precursor suggested the formation of molybdenum oxides around 430 °C (703 K). Thus, a range of deposition temperatures varying from 350 to 630 °C (623-903 K) was explored to investigate the effects on the nature of the molybdenum oxide films. X-ray diffraction (XRD) results showed that the films consisted of α-MoO₃ phase at deposition temperatures ranging from 400 to 560 °C (673-833 K). Crystalline α-MoO₃ films can be obtained from molybdenum dioxide acetylacetonate precursor, without need of a post-annealing treatment. The best crystalline quality was found in films having needle-like crystallites grown at deposition temperature of about 560 °C (833 K), which exhibit a strong (0 1 0) preferred orientation and a transparent visual appearance.