Ensemble Monte Carlo simulations have been carried out to investigate the effects of different capture cross-sections, trap densities and trap energy levels on the characteristics of GaN MESFETs. The simulation results show that deeper traps produce higher current collapse in comparison to shallow centres. Not surprisingly the simulation results show that increasing the trap density and trap cross-section decrease the output drain current. Simulations of the effect of modulating the gate bias have also been studied to test the device respond and derive the frequency bandwidth. The maximum cut-off frequency and transconductance of a 0.3 μm gate-length GaN MESFET including trapping effects are calculated to be 25 GHz and 75 mS mm−1, respectively.

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