Analysis of the Stress-Wave Influence Parameters of Silicon MOSFET under 300V Drain Source Voltage

The traditional condition monitoring (CM) methods for power electronic devices are normally using electrical, magnetic, and thermal sensors. Alternatively, this paper uses the acoustic emission (AE) sensor to measure the mechanical stress wave generated inside the power electronic devices such as MOSFETs. Specifically, this paper focuses on the influence of measured surface, electrical parameters, and filters on the stress wave signal and the reliability of repeatability tests. Under the single pulse test with 300V drain-source voltage (Vds), the same acoustic emission sensor is pasted on the MOSFET package and the cooling surface with a coupling agent. The factors affecting stress waves are studied by changing electrical parameters and filters. The proposed experiments draw the following conclusions. 1) The characteristic parameters of the stress wave measured on the package and cooling surface of MOSFET are different under the same electrical parameters. 2) The characteristic parameters of the stress wave are almost unchanged under the same test conditions, which shows that the stress wave measurement method is reliable. 3) The peak value of the stress wave, the frequency domain amplitude, and energy are affected by Vds and turn-on time ( ton). Specifically, the gate voltage Vgs has no obvious trend to the amplitude. The impact on package is basically the same as the cooling surface.