Modeling of Carrier Trapping and Its Impact on Switching Performance

Requirements for compact modeling to predict circuit power loss accurately are the focus of this investigation. Most important is the capturing of the differences between an ideal carrier reaction within the used devices and the reality during circuit operation. For this purpose the carrier trapping/detrapping, which occurs during circuit operation, has to be modeled accurately in addition to the conventional device characteristics. Carrier trapping events prevent device operation according to the ideal carrier dynamics and result in energy losses. It is verified that the influence of the carrier trapping, extracted by dc measurements, is not sufficient. Additionally, the dynamic switching performance must be precisely analyzed to extract the time constants involved in the carrier-trapping events. This is achieved by compact modeling based on solving the complete Poisson equation, which provides a simple and accurate modeling approach.