Nb₂O₅/SnO₂ Heterojunctions Designed as Optical Absorbers and Microwave Band Filters

Abstract

Herein, a 200 nm thick films of SnO2 are deposited onto Nb2O5 thin substrates (100 nm) to construct an isotype Nb2O5/SnO2 (NSO) heterojunction devices. The device is constructed using a thermal coating method in a vacuum media of low pressure reaching 10−5 mbar. NSO heterojunctions represent two amorphous/amorphous‐stacked layers that exhibit enhanced light absorption exceeding 170% and 120% in the visible and infrared regions of light spectrum, respectively. In addition, the interface under study displays band conduction offset of 0.60–0.90 eV and valence bad offset of 0.53–0.83 eV, respectively. The NSO device, which is treated as a planner microwaves resonators by contacting it with two Ohmic Pt electrodes, shows AC electrical conduction by the correlated barrier hopping within correlated barriers of average heights of 0.127 eV. Electrical conduction is actualized within scattering time constant of 0.27 ns. NSO microwaves resonators display gigahertz cutoff frequency spectra that suit 6G technology applications. The cutoff limit can be engineered in the range of 1.0–12.0 GHz by altering the driving frequency value. The features of the NSO heterojunctions nominate them for use in optoelectronic, which require high light absorption. The heterojunction devices are also promising for potential use in microwave technology a 6G bands filters.