Characterization and applications of ITO/SeO2 interfaces

Abstract

Herein, indium tin oxide (ITO) thin film substrates are employed to fabricate ITO/SeO2 multifunctional interfaces. The effects of ITO substrates on the physical properties of SeO2 thin films are explored by the structural, morphological, optical and electrical characterization techniques. Amorphous SeO2 thin films are prepared by the thermal evaporation technique under a vacuum, pressure of 10– 5 mbar, that exhibit induced crystallization process when it is coated onto ITO substrates. ITO substrates additionally forced evolution of SeO2 nanotubes of diameters of 10–20 nm. Optically, coating SeO2 onto ITO substrates enhance the light absorbability in the visible and infrared ranges of light, blue shifted the energy band gap of SeO2 and forced dielectric resonance at 3.42 eV and 2.27 eV. Electrically, the ITO/SeO2/Ag devices display negative conductance and negative capacitance effects in the frequency domains of 0.01–0.35 GHz and 0.01–1.80 GHz, respectively. These features are beneficial for signal amplification and noise reduction in electronic circuits. In addition, the impedance spectroscopy analyses shows that the ITO/SeO2/Ag devices operate at high impedance mode in the microwave frequency domain. It also shows band stop filter characteristics that are well performing in the gigahertz frequency domain. The features of the band stop filter nominate the ITO/SeO2/Ag devices for use in 5G technologies.