Investigation of MoS2 Based Dual Gate MOSFET as a H2 Sensor Considering Catalytic Metal Gate Approach

Abstract

In this paper, the authors have tried to develop a simulation model for MoS2 or molybdenum disulfide based dual gate MOSFET (MoS2 DG-MOSFET) by considering catalytic metal gate approach to detect hydrogen (H2) gas molecules. Here, the simulation model of the proposed gas sensor has been assessed by incorporating the NEGF method in SILVACO ATLAS. In addition to this, the performance of the device has been evaluated by studying the shift in its threshold voltage against the variation in metal (gate) work-function with the gas exposure. The results obtained exhibit maximum shift in the threshold voltage (precisely 232 mV) for a metal work function change of 200 meV. Moreover, the paper also demonstrates the change in density of states, transmission probability etc. in the presence of H2 gas molecules. The proposed device overcomes the challenges associated with conventional Si-based MOSFETs for gas sensing, takes care of scalability of a sensor and provides improved OFF-state leakage current along with large ION and IOFF ratio.