High frequency characteristics of MESFETs

Abstract

Using a self consistent two-dimensional Monte Carlo (MC) simulation, the high frequency characteristics of a state of the art planar MESFET structure are calculated. The dependence of the Y parameters on the gate bias voltage, drain bias voltage, channel doping, and gate position along the channel is discussed. In addition, the MC simulation and a two-dimensional drift-diffusion (DD) model were compared. This was accomplished by comparing the current gain and Y parameters of the transistor over a wide range of frequency predicted by the two approaches. The MC approach led to a 40% higher unity current gain frequency over the DD model.