Nonlinear charge trapping effects on pulsed I/V characteristics of GaN FETs

Nonlinear dynamic characterization of 1-mm GaN FETs is carried out by means of pulsed waveform excitations, applied through a recently proposed measurement setup. Due to fast trap capture phenomena, standard narrow-pulsed I/V characteristics are found to deviate from the ideal behavior. In this paper, the effects of the nonlinear charge trapping on pulsed I/V characteristics are experimentally observed thanks to a particular feature of the adopted measurement setup, which allows the monitoring of the DC drain current components of the pulses. In addition, the progressive degradation of the device performance due to charge trapping phenomena at increasing excitation amplitudes is shown by means of a new pulsing procedure.