The application of established test routines like power cycling to wide bandgap devices may be not as straightforward as it seems: When power cycling silicon carbide MOSFETs, the original purpose of triggering package related degradations under application-like and accelerated conditions might be influenced by device related changes during the test, such as carrier trapping, which may lead to a shift in the threshold-voltage $V_{\mathrm{th}}$ and, thus, in the operating point. With the aim to track the $V_{\mathrm{th}}$ shift during power cycling in order to separate the mechanisms—i.e., to indicate and quantify the different overlapping effects—a novel inline $\Delta V_{\mathrm{th}}$ measurement approach is proposed, which can be integrated in existing power cycling test benches with only minor adaptions. First power cycling results with $\Delta V_{\mathrm{th}}$ monitoring reveal a shift in the operating point leading to an early failure detection in conjunction with a $V_{\mathrm{th}}$ shift.

中文翻译：

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功率循环测试中SiC MOSFET阈值电压漂移的测量方法

已建立的测试例程（如功率循环）在宽带隙器件上的应用似乎并不像看起来那么简单：当功率循环碳化硅MOSFET进行功率循环时，在类似应用和加速的条件下触发与封装相关的性能下降的最初目的可能会受到与器件相关的影响。测试过程中的变化，例如载流子捕获，可能会导致阈值电压发生变化 $ V _ {\ mathrm {th}} $因此，在工作点上。旨在跟踪$ V _ {\ mathrm {th}} $ 功率循环期间的移位以分离机制（即指示和量化不同的重叠效应） $ \ Delta V _ {\ mathrm {th}} $提出了一种测量方法，该方法只需很小的改动就可以集成到现有的功率循环测试台中。第一次电源循环结果与$ \ Delta V _ {\ mathrm {th}} $ 监控显示工作点发生了变化，从而导致了早期的故障检测以及故障诊断。 $ V _ {\ mathrm {th}} $ 转移。