Practical Design of 4H-SiC Superjunction Devices in the Presence of Charge Imbalance


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In the ideal case, superjunction (SJ) drift regions theoretically exhibit a linear relationship between specific-on resistance Ron,sp and blocking voltage VBR, but this requires perfect charge balance between the alternating n and p pillars. If any degree of imbalance exists, the relationship becomes quadratic, similar to a conventional drift region, although with somewhat improved performance. In this work, we analyze superjunction drift regions in 4H-SiC under realistic degrees of charge imbalance and show that, with proper design, a reduction in specific on-resistance of 2~10x is possible as long as the imbalance remains less than ±20%.



Edited by:

Robert Stahlbush, Philip Neudeck, Anup Bhalla, Robert P. Devaty, Michael Dudley and Aivars Lelis




M. M. Alam et al., "Practical Design of 4H-SiC Superjunction Devices in the Presence of Charge Imbalance", Materials Science Forum, Vol. 924, pp. 563-567, 2018

Online since:

June 2018




* - Corresponding Author

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