In this article, we investigate a novel optimized 4H-SiC U-shaped trench-gate MOSFET (UMOSFET) structure, which features an electric field modulation region below the P-body. This region consists of a p-type region and an n-type region, while the p-type region is wrapped by the n-type region. We use the p-type region to reduce the electric field at the P+ shielding layer and the gate oxide. The reduced electric field increases the breakdown voltage (BV) of the optimized UMOSFET substantially. The n-type region can also improve the ON-state characteristics of the UMOSFET. Under the combined action of the p-type region and the n-type region, the BV and figure of merit increased by 25.2% and 120.5%, respectively. Moreover, the specific ON-resistance dropped by 40.8%.

中文翻译：

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具有 P 体下方电场调制区的 4H-SiC UMOSFET

在本文中，我们研究了一种新颖的优化 4H-SiC U 形沟槽栅极 MOSFET (UMOSFET) 结构，该结构在 P 体下方具有电场调制区。该区域由p型区域和n型区域组成，而p型区域被n型区域包裹。我们使用 p 型区域来降低 P+ 屏蔽层和栅极氧化物处的电场。减小的电场显着增加了优化的 UMOSFET 的击穿电压 (BV)。n 型区还可以改善 UMOSFET 的导通特性。在p型区和n型区的共同作用下，BV和品质因数分别增加了25.2%和120.5%。此外，比导通电阻下降了 40.8%。