Modelling and Systematic Investigation of Gas Sensing Utilizing Metal Oxide Semiconductors: Insights into Sensor Design Principles

Metal oxide semiconductor (MOS) gas sensors have garnered significant attention and have been widely utilized across various fields. However, due to their complex sensing processes and nonlinear responses, the modeling, optimization and design of MOS sensors still remain challenging. Herein, we present a finite-element-method approach to model the behavior of MOS gas sensors. It was confirmed that the proposed model precisely reproduced the responses of different sensors over a wide concentration range. Based on the model, we systematically investigated how the sensor response was influenced by multiple factors such as adsorption isotherms, geometric parameters, material parameters, and electrical parameters. The simulation results not only closely align with existing experimental data and theoretical analysis, but also provide key insights for the optimization of MOS gas sensors. This work provides new methodologies for MOS sensor design and paves the way for high-performance MOS gas sensors.