SnGaO Alloy Ultraviolet Detector with Broadened Tunable Bandgap and Enhanced Responsivity

High-performance ultraviolet photodetectors have become critical components in many fields, in whose research Ga2O3 is widely used owing to its great performance and properties. In this study, the magnetron sputtering method is used to dope Sn into Ga2O3 based on sapphire, which widens the response range of Ga2O3 detectors and realizes bandgapengineering of SnGaO between 4.1 eV and 4.8 eV. Furthermore, via mask evaporation technology, interdigital electrodes are fabricated on SnGaO films, and a photoconductive ultraviolet detector with a symmetrical structure is developed. This device exhibited favorable detectivity in the ultraviolet band, and its response-peak wavelength can be freely adjusted. The detector with 54% Sn has an exceedingly low dark current lower than 10-10 A, an ultra-high switching ratio above the order of magnitude of 107 under 3 V bias voltage, and a superior responsivity of 90 A/W under 5 V bias voltage.