Performance Assessment of InGaN Double Gate Stack-Oxide MOSFET based Phosphine Gas Sensor: A Catalytic Metal Gate Approach

In this article, a computational assessment of InGaN Double Gate Stack-Oxide MOSFET (InGaN DGS-MOSFET) has been performed for the purpose of detecting phosphine (PH3) gas molecules. Here, the catalytic metal gate approach is used to develop the computational model of the gas sensor. Moreover, the performance metrics of this MOSFET based phosphine gas sensor is estimated by examining the comparative variation in the on-state current and threshold voltage in respect of metal (gate) work function modulation with the gas exposure. Sensitivity profile shows that the proposed device is capable of having 24% higher Vth sensitivity than silicon based DGS-MOSFET. Additionally, the device sensitivity is optimized by considering various channel materials such as SiGe, Si, and IGZO. In comparison with SiGe, Si and IGZO, InGaN-based DGS-MOSFET is capable of providing better Vth sensitivity for PH3 detection. Furthermore, the high-k gate oxide material is also optimized based on the sensitivity profile of the device.