Assessment of high-k gate stacked In2O5Sn gate recessed channel MOSFET for x-ray radiation reliability

Abstract

This work reports the effect of x-ray radiation on In2O5Sn based Transparent Gate Recessed Channel (TGRC) MOSFET with the high-k dielectric at the sub-20 nm regime. Reliability of TGRC-MOSFET with a high-k dielectric in harsh radiation environment (x-ray radiation in the 1k to 10k rad dose range after irradiation) is the main aim of this analysis using TCAD simulation. Results reveal that HfO2 as a gate stack on SiO2 improves the device reliability and enhances the drain current, hole trap density, threshold voltage shift, and radiation sensitivity as compared to Al2O3 and ZrO2 gate stack with 1k rad to 10 k rad radiation doses. Trap/de-trap model has been used for interface charging as well as insulator along with the electron-hole pair generation and recombination. Further, the thermal effect on threshold voltage and sensitivity has also been evaluated. Results suggest that the proposed device with a high-k dielectric is more reliable in the x-ray radiation environment at the sub 20 nm scale. This device finds enormous applications in the clinical and space environment along with signal amplification and a processing circuit.