Electron-hole pair evaluation in silicon dioxide SiO2 derived from rice husk ash as an insulating layer in MOSFET dosimeter using PHITS

Abstract

We assess the feasibility of using silicon dioxide (SiO₂) from rice husk ash (RHA) as an insulating layer in MOSFET dosimeters by calculating electron-hole pair formation induced by ionizing radiation with beam energies ranging from 2.5 to 6.0 MeV using PHITS. We used a 6 MV Varian Clinac 600C 10×10 cm² source from IAEA to simulate energy deposition. The stoichiometric composition and density of derived SiO₂ are based on a prior study by Fusinato et al. [Environ. Sci. Pollut. Res. 30, 21494 (2023)]. A 6MV linac reference model from Li et al. [PLoS ONE 17, e0261042 (2022)]. was used to calibrate the simulation setup. The result reveal an 8.37% difference between pure and derived SiO₂ due to their different densities, but a linear correlation between energy deposition and electron-hole pair formation was observed, which confirms that RHA-derived SiO₂ is a radiation-sensitive insulating layer material for MOSFET dosimeters.