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

摘要

With the combined use of the drift-diffusion (DD) model,experimental measured parameters and small-signal 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 = 4.5 V.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.