FIELD-EFFECT TRANSISTORS BASED ON REDUCED GRAPHENE OXIDE FILM FOR PHOTO AND RADIATION DETECTORS

The features of using dielectric layers of SiO2, Al2O3, and HfO2 in field-effect transistors based on reduced graphene oxide (RGO) films for detecting visible and ionizing radiation have been investigated. The influence of the dielectric layer on the electrical characteristics of the created field-effect transistors in DC and AC modes was studied based on an analysis of the dependencies of drain current and RGO film resistance on gate voltage. An increase in drain current, a decrease in RGO film resistance, and a shift of the charge neutrality point toward negative gate voltages were found under the influence of white light irradiation. It was established that irradiation with β-particles and γ-quanta from a 226Ra source causes a transformation of the capacitance-voltage characteristics of the obtained field-effect transistors based on the RGO film due to the formation of electrically active defects in the dielectric layer. The effectiveness of using various dielectric layers to create photo- and ionizing radiation detectors based on graphene field-effect transistors is discussed.