Modeling and Simulation Characteristics of a Highly-Sensitive Stack-Engineered Junctionless Accumulation Nanowire FET for PH3Gas Detector

In this manuscript, a Stack Engineered Junctionless Accumulation Nanowire FET (SE-JAM-NW FET) has been proposed for low - power and high sensitivity phosphine (PH3) gas detection applications. In comparison to a standard nanowire FET, the SE-JAM-NW FET is used at nanoscale dimensions because of its inherent benefits, including low cost, improved portability, low Off- state current and increased On-state current with low - power consumption. To implement the SE-JAM-NW FET as a phosphine gas sensor, four catalytic metals, Platinum (Pt), Rhodium (Rh), Iridium (Ir) & Palladium (Pd) have been employed as gate electrodes. For designing gas sensor, various electric parameters like potential, electron concentration, recombination rate and electron velocity are evaluated for PH3gas detection. To forecast the sensor’s response, analog characteristics like changes in drain current, transconductance & output conductance are being simulated for different catalytic metal work functions (200 meV, 150 meV, 100 meV and 50 meV) at the gate electrode. The variation in On-state current-to-Off-state current ratio (IOn/IOff), On-state current (IOn) & subthreshold leakage current (IOff) for sensing the gas molecules has been used to quantify the sensitivity. The effects of silicon pillar-based radius variation and channel length variation on the sensitivity-based parameters are also investigated. Each catalytic metal exhibits improved sensitivity with increased channel length and decreased radius. The outcomes of the ATLAS 3-D device simulator’s numerical simulation closely match with those of the derived analytical model.