Acoustic Emission-Based Experimental Analysis of Mechanical Stress Wave in IGBT Device

In this paper, based on acoustic emission (AE) monitoring and digital filtering technology, the low and high frequency components in the switching mechanical stress wave (MSW) of insulated gate bipolar transistor (IGBT) device were discovered for the first time. Then, the effects of turn-off current on the low and high frequency components were studied. The obviously linear relationship was found between the low frequency component and the turn-off current, and the low frequency component could closely follow the change of turn-off current, showing that the low frequency component was strongly related with turn-off current. The high frequency component contained two pulse waves with the inverse phase, single frequency and high similarity, and it was weakly linear related with or not linear related the turn off current, and it was insensitive to the change of turn-off current, proving that the turn-off current was not the main cause of the high frequency component. Besides, the repeatability test was performed on another IGBT device, showing good repeatability for the experimental results.