Experimental and numerical results correlation during extreme use of power MOSFET designed for avalanche functional mode

Cost, weight and size reduction constrained designers of power electronic for micro hybrid vehicle to use power MOSFET under extreme conditions like avalanche mode. This paper shows the influence of the solder voids onto the die temperature distribution of a specifically designed power MOSFET. In the first part of this paper, a methodology is presented to perform fast dynamic temperature measurements during MOSFET avalanche (400 A–80 μs). In the second part of the paper, a comparison between experimental results and finite elements electro-thermal simulation is shown for power MOSFET operating in high conduction mode (500 A–100 ms). Finally the correlated numerical model is used to evaluate the sensitivity to solder voids of the chip temperature distribution.