## 3 Results and Discussion
### Optical Properties
According to the literature [41], various factors may affect the energy band gap of vanadium oxide, for example, the deposition method, the thickness of the thin film or the type of substrate [42, 43, 44, 45, 33]. Similar values of the energy band gap have been obtained in the literature [44], where the authors studied annealed V\({}_{2}\)O\({}_{5}\) at various temperatures. The results ranged from 2.32 to 1.98 eV with increasing temperature. The authors pointed out that thin films prepared at room temperature were stoichiometric, whereas at elevated temperatures they were substoichiometric. [PERSON] et al. [46] concluded that an increase in the deposition temperature causes a decrease in the optical energy band gap due to the formation of oxygen ion vacancies. However, heat treatment in O\({}_{2}\) caused an increase in band gap energy and transmission coefficient due to the partial filling of the vacancies. Other \begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline \multirow{2}{*}{**Ar:O\({}_{2}\) Ratio**} & \multirow{2}{*}{\begin{tabular}{c} **Deposition** \\ **Rate (Å/s)** \\ \end{tabular} } & \multirow{2}{*}{\begin{tabular}{c} **Average** \\ **Transmission** \\ **(\%)** \\ \end{tabular} } & \multirow{2}{*}{\begin{tabular}{c} **\(\lambda_{\text{cut-off}}\) (nm)** \\ \end{tabular} } & \multirow{2}{*}{\begin{tabular}{c} **E\({}_{\text{g}}\) (eV)** \\ **(\Omega/[\(\overline{\text{\text{\text{\text{\text{\text{\text{\text{\text{\text{\text{\text{\text{\text{\text{\text{   }}}}}}}}}}}}}}\)\) \\ \end{tabular} } & \multirow{2}{*}{\
\begin{tabular}{c} **Sheet** \\ **Resistance** \\ **(\Omega cm)** \\ \end{tabular} } & \multirow{2}{*}{
\begin{tabular}{c} **Resistivity** \\ **(\Omega cm)** \\ \end{tabular} } \\ \hline
8:1 & 2.68 & 21.8 & 371 & 2.01 & 2.99-10\({}^{5}\) & 9.10 & 2.64-10\({}^{-8}\) \\
7:1 & 2.46 & 24.5 & 386 & 1.91 & 2.06-10\({}^{6}\) & 6.70-10\({}^{1}\) & 1.17-10\({}^{-8}\) \\
6:1 & 2.01 & 36.2 & 405 & 1.99 & 3.42-10\({}^{6}\) & 1.11-10\({}^{2}\) & 3.48-10\({}^{-7}\) \\
5:1 & 1.79 & 39.1 & 447 & 2.00 & 6.23-10\({}^{6}\) & 2.28-10\({}^{2}\) & 3.64-10\({}^{-7}\) \\
4:1 & 1.42 & 48.5 & 454 & 2.06 & 6.98-10\({}^{6}\) & 2.16-10\({}^{2}\) & 3.31-10\({}^{-6}\) \\
3:1 & 1.02 & 49.9 & 466 & 2.07 & 9.44-10\({}^{6}\) & 3.07-10\({}^{2}\) & 3.12-10\({}^{-6}\) \\
2:1 & 0.87 & 51.1 & 470 & 2.08 & 7.14-10\({}^{7}\) & 2.04-10\({}^{3}\) & 5.90-10\({}^{-7}\) \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Summary of the properties of deposited vanadium oxide thin films prepared with various Ar:O\({}_{2}\) gas ratios during magnetron sputtering. Figure 4: Results of: (a) transmission spectra of V\({}_{x}\)O\({}_{y}\) thin films deposited with various Ar:O\({}_{2}\) gas ratios during the magnetron sputtering process and (b) the average transmission of vanadium oxides in the VIS wavelength range. authors confirmed that a higher deposition temperature causes a decrease in optical band gap energy [43], but there are also reports that point to the opposite behaviour [47]. Other authors [32] reported an optical band gap energy equal to 1.87 and 2.1 eV for amorphous V\({}_{2}\)O\({}_{5}\) with different thicknesses, which is also in agreement with the results reported here.