Structural and optical characterization of DC magnetron sputtered molybdenum oxide films

Thin films of molybdenum trioxide were deposited on glass substrates employing direct current (DC) magnetron sputtering by sputtering of molybdenum at different oxygen partial pressures in the range 8 × 10⁻⁵–1 × 10⁻³ mbar and at a substrate temperature of 473 K. The glow discharge characteristics of magnetron cathode target of molybdenum were studied. The influence of oxygen partial pressure on the structural and optical properties of molybdenum trioxide films was investigated. The films formed at an optimum oxygen partial pressure of 2 × 10⁻⁴ mbar were polycrystalline in nature with orthorhombic α- phase and an optical band gap of 3.16 eV. The refractive index of the films formed at an oxygen partial pressure of 2 × 10⁻⁴ mbar decreased from 2.08 to 1.89 with increase of wavelength from 450 to 1,000 nm, respectively. Paper presented at the Third International Conference on Ionic Devices (ICID 2006), Chennai, Tamilnadu, India, Dec. 7–9, 2006.