Gate Oxide Induced Reliability Assessment of Junctionless FinFET-Based Hydrogen Gas Sensor

Gate oxide plays a crucial role in the performance of nano-scaled emerging devices. In FET-based sensors, gate-oxide-induced reliability analysis is essential for credible sensing. In this paper, using well-calibrated TCAD models, we analyzed the role of gate-induced drain leakage (GIDL) in a Junctionless FinFET-based Hydrogen (H2) gas sensor. Owing to high diffusivity and solubility, the Palladium (Pd) metal is employed as the gas-sensing surface, where the absorbed H2 molecules modulate the effective work function and, in turn, the threshold voltage $(V\text{th}})$, opted as primary sensing merit. In a Junctionless device, the heavily doped and fully depleted channel leads to significant band overlapping between the channel and drain regions, in turn, causes band-to-band tunneling. Therefore, a proper design guideline that governs the effective channel conduction modulation is worth needed for the reliable operation of an H2 sensor.