Investigating the reliability of SiC MOSFET body diodes using Fourier series modelling
Investigating the reliability of SiC MOSFET body diodes using Fourier series modelling
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DOI：
10.1109/ecce.2014.6953427
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发表时间：
2014-11
期刊：
影响因子：
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通讯作者：
R. Bonyadi;O. Alatise;S. Jahdi;J. Hu;L. Evans;P. Mawby
中科院分区：
文献类型：
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作者：
R. Bonyadi;O. Alatise;S. Jahdi;J. Hu;L. Evans;P. Mawby
利用双极扩散方程的傅里叶级数解，研究了SiC MOSFET体二极管在反向恢复过程中的鲁棒性。如果基极电流和体电阻两端的电压降足以正向偏置寄生BJT，则体二极管反向恢复期间可能发生寄生双极闩锁。SiC MOSFET具有极低的载流子寿命和薄的外延漂移层，这意味着体二极管恢复期间的dV/dt可能相当高。该dV/dt与寄生漏极到体电容耦合可引起体电流。本文介绍了一种新的评估SiC MOSFET体二极管反向恢复过程可靠性的方法。研究了开关速率、寄生电感和载流子寿命对寄生BJT激活的影响。
Using the Fourier series solution to the ambipolar diffusion equation, the robustness of the body diodes of SiC MOSFETs during reverse recovery has been studied. Parasitic bipolar latch-up during the reverse recovery of the body diode is a possible if there is sufficient base current and voltage drop across the body resistance to forward bias the parasitic BJT. SiC MOSFETs have very low carrier lifetime and thin epitaxial drift layers, which means that the dV/dt during the recovery of the body diode can be quite high. This dV/dt coupled with the parasitic drain-to-body capacitance can cause a body current. The paper introduces a new way of assessing the reliability of SiC MOSFETs during the reverse recovery of the body diode. The impact of switching rates, parasitic inductances and carrier lifetime on the activation of the parasitic BJT has been studied.