A compact model of MoS2 field-effect transistors from drift-diffusion to ballistic carrier transport regimes

Abstract

In this letter, a compact model for charge and drain current in molybdenum disulfide (MoS2) field-effect transistors (FETs) is developed, which is valid from ballistic to quasi-ballistic to drift-diffusion electronic transport regimes. Considering the influence of trap charges in MoS2 transistors, a physical-based and analytical charge model is derived. Based on the virtual source model which applies to both ballistic and quasi-ballistic transports, the carrier number density and current expressions are combined to yield the current-voltage (I-V) characteristics. Furthermore, the presented model is validated by experimental data as well as recently reported simulations for MoS2 FETs with different gate lengths. It shows that our model is accurate, straight-forward, scalable and compatible for short- and long-channel devices.