Sinusoidal Steady State Analysis on 4H-SiC Buried Channel MOSFETs

With the combined use of the drift-diffusion (DD) model, experimental measured parameters and small-signa1 sinusoidal steady-state analysis, we extract the Y -parameters for 4H-SiC buried-channel metal oxide semiconductor field effect transistors (BCMOSFETs). Output short-circuit current gain G and Mason's invariant U are calculated for extrapolating unity current gain frequency in the common-source configuration fT and the maximum frequency of oscillation fmax, respectively. Here fT = 800 MHz and fmax = 5 GHz are extracted for the 4H—SiC BCMOSFETs, while the field effect mobility reaches its peak value 87cm2/Vs when VGS = 4.5V. Simulation results clearly show that the characteristic frequency of 4H-SiC BCMOSFETs and field effect mobility are superior, due to the novel structure, compared with conventional MOSFETs.