Investigations into the robustness of the peak turn-on current slope method for junction temperature sensing in p-GaN HEMTs

In this paper, the robustness of a junction temperature sensing method using the peak of the turn-on current slope for enhanced p-GaN high-electron-mobility transistors is investigated in detail. With the help of a repetitive hard-switching test platform, compared to other temperature-sensitive electrical parameters, it is found that the maximum slope of the flowing current at the turn-on transition shows no trend in degradation, regardless of the applied switching stress. This parameter decreases solely with the increase in junction temperature, showing excellent temperature-dependent linearity. Furthermore, the applicability of this method to the detection of junction temperature under different external gate resistances and drain voltages is verified. The sensed junction temperatures are carried over to calculate the thermal resistance, which is also extracted by advanced thermal characterization test equipment as a reference. Therefore, based on the versatility, convenience and accuracy, the peak of the rising drain current slope has been proven to be the preferred alternative in system applications to detect junction temperatures.