In this letter, planar floating limiting rings (FLRs) and trench FLRs with different trench depths for the 4H-SiC junction barrier Schottky (JBS) rectifiers are analyzed and compared with simulations and experiments. Compared with the planar FLRs, the experimental results present that the first ring spacing window that termination efficiency exceeds 80% of the parallel plane breakdown voltage (BV) can be widened and termination area can be reduced at the same BV by adopting the trench FLRs. The simulations also indicate that there is an optimal trench depth for the trench FLRs and a smaller sidewall angle can achieve better device performance. Additionally, the repetitive avalanche current stress measurements imply that the trench FLRs has better robustness regarding the BV shift, achieving better device reliability.

中文翻译：

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4H-SiC结势垒肖特基整流器沟槽浮动限位环的特性和鲁棒性

在这封信中，分析了用于 4H-SiC 结势垒肖特基 (JBS) 整流器的具有不同沟槽深度的平面浮动限制环 (FLR) 和沟槽 FLR，并与模拟和实验进行了比较。与平面FLR相比，实验结果表明，采用沟槽FLR可以扩大端接效率超过平行平面击穿电压（BV）80％的第一环间距窗口，并在相同的BV下减小端接面积。模拟还表明，沟槽 FLR 存在最佳沟槽深度，较小的侧壁角可以实现更好的器件性能。此外，重复的雪崩电流应力测量意味着沟槽 FLR 在 BV 偏移方面具有更好的鲁棒性，从而实现更好的器件可靠性。