We report on the effects of thermal annealing on the structural and electrical properties of Vanadium Oxide (V OX) thin films. The annealing temperature and duration as well as the annealing environment were varied to study the effect of such variations on the V OX film resistivity, temperature coefficient of resistance (TCR), and electrical low frequency noise (1/f). The experiments were performed with the device under different experimental conditions that include vacuum, oxygen and an inert gas (argon) environment. The device performance was studied for three annealing different temperatures: 100°C, 200°C and 250°C, with annealing times varying from 15 min to 30 min. The results show a consistent increase in resistance, with larger changes following higher temperature anneals. The influence on TCR and noise was more significant for devices annealed at 200°C or above in vacuum or in argon. X-ray diffraction studies (XRD) show that high annealing temperatures mark the onset of micro-crystallinity, with various stable and metastable phases appearing in the amorphous V OX film matrix.
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