Numerical analysis of the gate voltage dependence of the series resistances and effective channel length in submicrometer GaAs MESFETs

A detailed numerical analysis of the source and drain parasitic resistances and effective channel length of state-of-the-art GaAs MESFETs is presented. Two-dimensional simulations are used to evaluate different criteria (physical and electrical) for defining the device parameters of interest, as well as to study their gate voltage dependence. To this purpose a novel criterion which provides a simple procedure to determine the series resistances as a function of gate bias is proposed