A novel graphene field-effect transistor for radiation sensing application with improved sensitivity: Proposal and analysis

In this paper, a new radiation sensitive field-effect Transistor (RADFET) dosimeter design based on armchair-edge graphene nanoribbon (AGNR), for high performance low-dose monitoring applications, is proposed through a quantum simulation study. The simulation approach used to investigate the proposed nanoscale RADFET is based on solving the Schrödinger equation using the mode space (MS) non-equilibrium Green's function (NEGF) formalism coupled self-consistently with a two dimensional (2D) Poisson equation under the ballistic limits. The responsiveness of the proposed RADFET to the modulation of radiation-induced trapped charge densities is reflected via the threshold voltage, which is considered as a sensing parameter. The dosimeter behavior is investigated, and the impact of variation in physical and geometrical parameters on the dosimeter sensitivity is also studied. In comparison to other RADFETs designs, the proposed radiation sensor provides higher sensitivity and better scalability, which are the main requirements for futuristic dosimeters. The obtained results make the suggested RADFET dosimeter as a viable and attractive replacement to silicon-based MOS dosimeters.