Degradation indicators of power-GaN-HEMT under switching power-cycling

Abstract This paper describes the design of a power-cycling test bench to study the reliability of power-GaN-HEMT power switches. The aim of the presented paper is to study the measurable electrical consequences of internal degradation with aging. The shift of these measured parameters can be considered as reliability indicators. With the aim to decorrelate thermomechanical effects from internal GaN-specific degradation, the temperature was limited by choosing the stress parameters with the use of an infrared camera. The power-cycling test was designed with GaN-specific gate drivers to consider the pGaN-gate requirements. Thorough the power-cycling test we have tracked the evolution of electrical parameters that have been identified as degradation indicators. Finally, we have studied the link between the stress parameters and the degradation, as well as the correlation between different degradation indicators.