Vanadium oxide (VOx) films were deposited onto well cleaned glass substrates by bipolar pulsed reactive magnetron
sputtering at room temperature. Dependence of the structure, composition, optical and electrical properties of the films
on the pulsed power’s duty cycle has been investigated. The results from the X-ray diffraction (XRD) analysis show that
there was no remarkable change in the amorphous structure in the films with duty cycle can be observed. But chemical
analysis of the surface evaluated with x-ray photoelectron spectroscopy (XPS) indicates that decrease the duty cycle
favors to enhance the oxidation of the vanadium. The optical and electrical properties of the films were characterized by
spectroscopic ellipsometry and temperature dependent resistivity measurements, respectively. The evolution of the
transmittance, optical band gap, optical constants, resistivity and temperature coefficient of resistance (TCR) of the
deposited films with duty cycle was analyzed and discussed. In comparison with conventional DC sputtering, under the
same discharge atmosphere and power level, these parameters of the VOx films can be modified over a broad range by
duty cycle. Therefore adjusting the duty cycle during deposition, which is an effective way to control and optimize the
performances of the VOx film for various optoelectronic devices applications.
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