Complex Research on Amorphous Vanadium Oxide Thin Films Deposited by Gas Impulse Magnetron Sputtering

In this work, a complex examination of vanadium oxide thin films prepared by gas impulse magnetron sputtering with various Ar:O-2 gas ratios of 2:1 divided by 8:1 was conducted. X-ray diffraction revealed the amorphous nature of the prepared thin films, and scanning electron microscopy images showed that the thin films were crack-free and homogenous. Optical properties investigations revealed that a higher oxygen content in the Ar:O-2 atmosphere during sputtering caused an increase in transparency. The sample prepared with the highest amount of oxygen in the gas mixture during deposition had 51.1% of the average transmission in the visible wavelength range. A decrease in oxygen caused deterioration in the thin film transparency with the lowest value equal to 21.8%. Electrical measurements showed that the prepared thin films had a semiconducting character with either electron or hole conduction type, depending on the sputtering gas composition. A small amount of oxygen in the gas mixture resulted in the deposition of p-type thin films, whereas an increase in the amount of oxygen caused a change to n-type electrical conduction. Resistivity decreased with increasing Ar:O-2 ratio. The gas sensing response toward diluted hydrogen was investigated for all the VxOy thin films, but at low operating temperatures, only the p-type thin films exhibited a visible response.

Automated summary

This work examined vanadium oxide thin films prepared by gas impulse magnetron sputtering with different Ar:O-2 gas ratios. The results showed that the thin films were amorphous and crack-free, and the transparency increased with a higher oxygen content in the gas mixture during deposition. The electrical measurements revealed that the thin films exhibited either electron or hole conduction type, depending on the sputtering gas composition. The gas sensing response toward diluted hydrogen was visible only in the p-type thin films at low operating temperature.