Characterization of the Switching Behavior of Wide-Bandgap Semiconductors


Characterization of the Switching Behavior of Wide-Bandgap Semiconductors


Electromobility and electric flying are driving an increase in the power densities of power-electronic systems, which is enabled in particular by the fast-switching semiconductor technologies silicon carbide (SiC) and gallium nitride (GaN). The transient characterization of these wide-bandgap semiconductor devices is a major challenge and can be performed at ISEA by double-pulse tests. When measuring individual switching events, high demands are specified for the current and voltage measurement equipment, since this equipment must ensure sufficient bandwidth while minimizing the influence on the circuit to be measured at the same time.

One objective within the Research Training Group mobile is the analysis and evaluation of the measurement methodology in the double-pulse test bench. Existing current and voltage measurement equipment is analyzed such that the quality of the measurements and the resulting measurement errors can be evaluated. By simulating the measurement setup, the impacts of individual parameters such as bandwidth limitation, signal propagation times, parasitic elements or ambient temperatures on the overall result can be extracted and estimated. Based on these results, measurement series are carried out to map and validate the various parameter impacts on selected SiC and GaN switching cells. The sources of error in the measurement setup can be identified and subsequently minimized, for example by reducing the inductance introduced by a current sensor or compensating for the different signal propagation times of probes.



10/2019 - 09/2022