Monitoring of parameter stability of SiC MOSFETs in real application tests

Overview of Wide/Ultrawide Bandgap Power Semiconductor Devices for Distributed Energy Resources

“…This is needed to consider potentially critical parameter variations caused by BTI in specification limits and system designs. The most straightforward way of studying parameter drifts in real applications is by running long-term application tests, thereby doing intermediate read-outs, and finally extrapolating the drift toward end-of-life [178].…”

“…In this setup, source and drain terminals are grounded, and the gates of devices are stressed at datasheet max-levels (V GH,max , V GL,min , and T VJ,max ) using pulsing frequencies of up to 500 kHz. Such high frequencies are used to achieve a considerable number of switching events within a reasonable stress time, e.g., 1000 h. This is essential since it was shown earlier [177], [178] that V TH drift under ac stress conditions follows a power law that depends on the number of switching cycles (N Cycles ) given by V TH = A 0 • (N Cycles ) n . In this expression, A 0 represents a bias-and temperature-dependent prefactor and the power law exponent n as the main parameter describing the evolution of the timeand frequency-dependent V TH drift.…”

Robustness of SiC MOSFETs under Repetitive High Current Pulses

“…While this slightly increases the commutation loop it also minimizes the components on the DUT board. The biggest advantage of this configuration is that the DUT can be characterized intermediately with dedicated high precision equipment without suffering from the influence of the DC link capacitors, similar to the approach described in [1]. An edge connector with the gate drive and high voltage signals enables the easy removal of the DUT board from the test bench to perform the intermitted characterization measurements.…”

“…Not only motivated by the increasing demand for products with highly efficient power electronics the technology has reached a level where it is mass market ready, especially with respect to reliability. Although there are new degradation phenomena such as the dynamic gate instability [1,2] the robustness of SiC MOSFETs continues to increase. For example, [3] has studied the behavior of SiC MOSFETs under repeated Short Circuit (SC) to investigate their robustness when such SC pulses are used to limit the over-voltage stress caused by inrush currents into a DC link capacitor.…”