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In this work, a complex examination of vanadium oxide thin films prepared by gas impulse magnetron sputtering with various Ar:O2 gas ratios of 2:1 ÷ 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:O2 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:O2 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. [ABSTRACT FROM AUTHOR]

In this work, a complex examination of vanadium oxide thin films prepared by gas impulse magnetron sputtering with various Ar:O2 gas ratios of 2:1 ÷ 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:O2 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:O2 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.

Copper sulphide CuS was deposited on three substrates; glass, Indium Tin Oxide (ITO) and Ti by using spray pyrolysis deposition (SPD). After depositing CuS thin films on the substrates at 200 °C, they were annealed at 50, 100, 150, and 200 °C for 1 hour. Structural measurements revealed covellite CuS and chalcocite Cu 2 S phases for thin films before and after annealing at 200 °C with changes in intensities, and only covellite CuS phase for thin films after annealing at 50, 100, and 150 °C. Morphological characteristics show hexagonal-cubic crystals for the CuS thin film deposited on glass substrate and plates structures for films deposited on ITO and Ti substrates before annealing, these crystals became bigger in size and there were be oxidation and some agglomerations in some regions with formation of plates for CuS on glass substrate after annealing at 200 °C. For Hall Effect measurements, thin films sheet resistivity and mobility increased after annealing while the carrier concentration decreased. Generally, the thin film deposited on ITO substrate had the lowest resistivity and the highest carrier concentration before and after annealing. The thin film deposited on Ti substrate had the highest mobility before and after annealing, which makes it the best thin film for device performance. The objective of this research is to show the improvement of thin films electrical properties especially the mobility after annealing those thin films. [ABSTRACT FROM AUTHOR]