“…Even in the application notes [8], where an electrothermal analysis of an insulated gate bipolar (IGBT) GaN transistor is presented, this problem is not discussed. Analyzing several other publications devoted to bipolar structures such as diodes, [9][10][11][12], IGBTs [13], Peltier modules [14], heterojunction bipolar transistors (HBTs) [15], we find that this problem is also not tackled. We do not want to judge if the reported results are fully correct, however, since there are no models details reported and it is not possible to confirm if all the results are fully validated.…”