Nanocomposites based on porous silicon and reduced graphene oxide for ionizing radiation sensing

Abstract

In this study, the field-effect transistor (FET) based on the oxidized porous silicon (PS) – reduced graphene oxide (rGO) sandwich-like composite has been created. The electrical characteristics of the obtained FET were studied in both DC and AC modes. I-V curves and switching characteristics of the PS–rGO-based FET were analyzed. An increase in resistance and a decrease in capacitance of the experimental structures have been found in the 25 Hz − 1 MHz frequency range due to the joint action of α-, β-, and γ-radiation. The parameters of the equivalent circuit model of the PS–rGO-based FET before and after irradiation with 226Ra isotope have been determined using the impedance spectra. The formation of radiation-induced defects and the charge accumulation in the PS layer is considered a possible mechanism of the ionizing radiation influence on the graphene FET conductivity. The FET based on the PS–rGO structures has a high potential for application in ionizing radiation sensors due to the linear dependencies of resistance and capacitance on the irradiation duration.