Modeling and TCAD Simulation of 1/f Noise Dynamics in Two-Dimensional Material-Based FETs

Two-dimensional (2D) materials such as graphene and MoS2 are promising channel materials for radio-frequency and low-power eld-e ect transistors (FETs). Their low frequency noise is dominated by the random capture and emission of channel carriers by defects in the gate dielectric, a mechanism that limits circuit performance but also provides a non-destructive probe of dielectric quality. This thesis develops and val idates a physics-based model of this trappingdetrapping noise in 2D FETs. Each defect contributes a Lorentzian spectrum weighted by its occupancy and by its elec trostatic coupling to the channel, with capture and emission rates computed from the elastic and phonon-assisted trap-assisted tunneling formulations as implemented in the commercial TCAD simulator. An equivalent-circuit analysis shows that the density of-states capacitance of the channel cancels out of the input-referred noise when the actual transconductance is used. The implemented rates agree with TCAD, and the comparison revealed an electronhole asymmetry in the simulator, which led to a sym metric formulation of the hole rates. For a graphene FET, the model reproduces TCAD spectra of single and multiple traps from 10 Hz to 10 GHz, clarifying the roles of trap depth, trap energy, bias and phonon-assisted transitions, and, with the trap density as the only tting parameter, it reproduces measured 1/f spectra at di erent bias points. The model is then extended to correlated mobility uctuations through a closed-form expression and applied to a MoS2 FET, providing a computationally e cient alterna tive to TCAD for the noise analysis of 2D-channel transistors.