Sensitivity Investigation of Junctionless Gate-all-around Silicon Nanowire Field-Effect Transistor-Based Hydrogen Gas Sensor

In this work, a junctionless(JL) gate all around (GAA) silicon nanowire field-effect transistor sensor for the detection of hydrogen (H-2) has been carried out. The sensors are designed to specify hydrogen gas (H-2) existence. Unsafe conditions can result if hydrogen escapes and accumulates in an enclosed space throughout the purifying process; this is why we try to investigate technologically ultra-small-scale hydrogen gas sensor devices. The sensor also showed satisfactory characteristics for ensuring safety when handling hydrogen and remarkable selectivity for monitoring H-2,H- among other gases, such as LPG, NH3, and CO. The temperature and palladium (Pd) gate work function variations in the translation processes are well-thought-out throughout a change in palladium (Pd) gate work function following exposure to the hydrogen gas molecule (H-2). Due to its sensitivity to H-2 gas, palladium (Pd) is employed as a gate electrode in H-2 gas detection. Shift in threshold voltage (V-th), Ion and Ioff as a result of the metal work function at the gate changing when gas is present; these changes can be regarded as sensitivity parameters for sensing hydrogen gas molecules. ATLAS-3D device simulator has been conducted at low drain bias voltage (0.05V). This study focuses on temperature variation (300K to 500K) and palladium (Pd) metal gate work function variations (5.20eV to 5.40eV) to examine the existence of hydrogen molecule(H-2) and its effect on the performance of junctionless SiNW-GAA field-effect transistor gas sensors. When the sensitivity (S-IOFF), of proposed JL-GAA-SiNWFETis compared with GAA-MOSFET and bulk MOSFET, JL-GAA-SiNWFET shows improved sensitivity. The results show that as 150mV Pd work function shifts at the gate, the sensitivity improvement with JL-GAA-SiNWFET-based hydrogen gas sensors are 51.65% and 124.51% compared with GAA-MOSFET and MOSFET, respectively. High dielectric oxide (HfO2) and interface oxide (SiO2) is also employed at the gate to overcome electron tunneling. The study of this work proves that a silicon nanowire field-effect transistor with a junctionless gate all around catalytic palladium (Pd) metal gate is the best candidate for sensing hydrogen gas molecules than a bulk metal oxide semiconductor field-effect transistor (MOSFET).