Impact ionization in GaAs MESFETs

A method to measure impact ionization current in GaAs MESFETs is presented. The impact ionization current is then used to calculate the maximum electric field in the channel and the impact ionization coefficient. Data for the electron impact ionization coefficient in [110] GaAs are extended beyond previous studies by five orders of magnitude. Impact ionization is taken into account in a new gate current model.<<ETX>>