A Simple Method to Extract Trapping Time Constants of GaN HEMTs
This paper presents a simple method to extract the time constants associated with trapping effects observed in GaN HEMT devices. Instead of using specific and, sometimes, very expensive measurement systems, we propose a method that relies on common equipment present in all RF laboratories. The method uses measured information of a GaN power amplifier (PA) gathered from a VNA (small-signal gain collected for different gate-to source voltages) and a VSA (dynamic gain profiles obtained from a set of two-tone input signals with different separation frequencies). The paper starts by presenting the theoretical background of the proposed methodology followed by an experimental validation with a GaN HEMT PA.