A Study of 4H-SiC Semi-Superjunction Rectifiers for Practical Realisation

Abstract:

This paper discusses the design and simulation of 4H-SiC semi-SJ structures producing results that are below the unipolar limit, whilst also ensuring practical and cost-effective realisation. The results demonstrate that a semi-SJ structure with a 10° sidewall angle increases the implantation window of the device by 45%, relative to the full-SJ, whilst maintaining a high V_BD of ~2 kV and a low R_ON,SP. This design facilitates a wide implantation window with a reduced trench aspect ratio, significantly improving the practical realisation of the device. It also offers softer reverse recovery characteristics as a result of both the angled trench sidewall and the n-bottom assist layer (n‑BAL) which allows for the structure to be depleted gradually.

• Periodical: Materials Science Forum (Volume 1062)
• Pages: 514-518
• DOI: https://doi.org/10.4028/p-cxd7z3
• Online since: May 2022
• Authors: G.W.C. Baker*, Fan Li, Tian Xiang Dai, A. Benjamin Renz, Lu Yang Zhang, Yun Yi Qi, Vishal Ajit Shah, Philip Andrew Mawby, Marina Antoniou, Peter Michael Gammon
• Keywords: Schottky Barrier Diode, Semi-Superjunction, Simulation, Superjunction

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