A new vertical double-diffused metal oxide semiconductor field effect transistor (MOSFET) is presented based on the high- ${k}$ (Hk) MOSFET concept in this article with the step high- ${k}$ insulator, named as step Hk vertical double-diffused metal oxide semiconductor (VDMOS), to improve the electric field modulation effect. For step Hk VDMOS, the depletion is increased by the electric field modulation effect of step Hk insulator, which decreases the specific on-resistance of step Hk VDMOS compared to the conventional Hk VDMOS. The various thickness of the Hk insulator modulates the vertical electric field distribution in the drift region, which increases the breakdown voltage (BV) of the step Hk VDMOS. Meanwhile, an analytical model for novel step Hk VDMOS is obtained by solving the 2-D Poisson equation in an N-type drift region, and the 2-D Laplace equation in the step Hk region, which can reasonably explain the modulation effect of the step Hk region on the electric field distribution. The results show that the BV of the step Hk VDMOS is increased from 639 V of the conventional Hk VDMOS to 736 V with the same drift length of $42~\mu \text{m}$ . The theoretical results of the electrical characteristics are in good agreement with the results from numerical simulations.

中文翻译：

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通过改进电场调制，具有接近超级结极限的步进 Hk 绝缘体的新型垂直功率 MOSFET 击穿电压与特定导通电阻之间的关系

提出了一种新型垂直双扩散金属氧化物半导体场效应晶体管 (MOSFET) ${k}$ (Hk) 这篇文章中的 MOSFET 概念与步进高 ${k}$ 绝缘体，命名为step Hk垂直双扩散金属氧化物半导体（VDMOS），以改善电场调制效果。对于阶梯Hk VDMOS，由于阶梯Hk绝缘体的电场调制效应增加了耗尽，与传统的Hk VDMOS相比，这降低了阶梯Hk VDMOS的比导通电阻。Hk绝缘体的不同厚度调节了漂移区中的垂直电场分布，从而增加了台阶Hk VDMOS的击穿电压（BV）。同时，通过求解N型漂移区的二维泊松方程和阶梯Hk区的二维拉普拉斯方程，得到了新型阶梯Hk VDMOS的解析模型，可以合理解释电场分布上的阶梯 Hk 区域。 $42~\mu \text{m}$ . 电气特性的理论结果与数值模拟结果非常吻合。