  We present a physics-based compact model for two-dimensional (2D)
field-effect transistors (FETs) based on monolayer semiconductors such as MoS2.
A semi-classical transport approach is appropriate for the 2D channel, enabling
simplified analytical expressions for the drain current. In addition to
intrinsic FET behavior, the model includes contact resistance, traps and
impurities, quantum capacitance, fringing fields, high-field velocity
saturation and self-heating, the latter being found to play a strong role. The
model is calibrated with state-of-the-art experimental data for n- and p-type
2D-FETs, and it can be used to analyze device properties for sub-100 nm gate
lengths. Using the experimental fit, we demonstrate feasibility of circuit
simulations using properly scaled devices. The complete model is implemented in
SPICE-compatible Verilog-A, and a downloadable version is freely available on
the nanoHUB.org.
