Junctionless Spacer-Engineered SOI FinFET-Based Hydrogen Gas Sensor: Electrical Characterization and Sensitivity Analysis

This research presents a novel junctionless spacer-engineered gate stacked Silicon-On-Insulator (SOI) FinFET for hydrogen gas sensing. The study investigates the sensor’s transfer characteristics, energy band diagram and surface potential under varying pressures. Threshold voltage and switching ratio sensitivities are calculated to assess the sensor’s responsiveness. A maximum value of 125.64 for I<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">ON</inf>/I<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">OFF</inf> sensitivity and 0.24 for V<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">TH</inf> sensitivity is obtained at P=10<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-10</sup> Torr. Simulations performed on 3D ATLAS Silvaco tool reveal significant differences in performance between the junctionless (JLT) sensor and the one having a junction. Specifically, the JLT fin-based sensor demonstrates substantially improved sensitivity to hydrogen gas. The combination of improved sensitivity and the SOI FinFET architecture presents a promising approach for designing high-performance hydrogen gas sensors suitable for diverse applications using JLT SOI FinFETs.