Analysis of Nb-doped and undoped TiO₂ nanocoatings with varying dopant concentrations

Titanium dioxide (TiO₂) without doped and with different amounts of niobium (Nb) doped coating with thicknesses of ~ 100 nm were deposited on glass and n-Si substrates at room temperature by radio frequency magnetron sputtering. Nb doping ratios were determined as 0% (NTO-0), 3% (NTO-3), 5% (NTO-5), and 7% (NTO-7). Structural, morphological, and optical analyses of NTO-0, NTO-3, NTO-5, and NTO-7 samples on a glass substrate were performed. The X-Ray Diffraction method performed the structures’ crystallite quality. Quantitative elemental microanalysis of the structure was performed by scanning electron microscopy with the energy dispersive spectroscopy method. The surface morphologies of the structures were performed by the Atomic Force Microscope system. The transmittance spectra of the structures were performed by UV–Visible Spectrometer systems. The electrical properties of the Au/n-Si structure with TiO₂ interface layer doped 3% Nb depending on the frequency (between 100 kHz to 1 MHz) and the voltage (in the range of ± 4 V) using C–V and G/ω–V characteristics were obtained.