Structural and electrical characterization of magnetron sputtered MoO3 thin films

Thin films of molybdenum oxide were deposited on glass and crystalline silicon substrates using dc magnetron sputtering method by sputtering of molybdenum target in the presence of oxygen and argon gas mixture under various oxygen partial pressures in the range 8×10-5 – 8×10-4 mbar. The glow discharge characteristics of the molybdenum cathode under various oxygen partial pressures were studied. The effect of oxygen partial pressure on the core level binding energy, structure, mechanical and electrical properties of the films was systematically studied. The films formed at oxygen partial pressures < 2×10-4 mbar contained the MoO3 and MoO3-x phases. The films deposited at oxygen partial pressures of 2×10-4 mbar were stoichiometric with single phase orthorhombic α- MoO3. The electrical conductivity of films decreased from 4×10-5 to 1.6×10-6 Ω-1cm-1 with increase of oxygen partial pressure from 8×10-5 to 8×10-4 mbar.