A novel GaN trench gate vertical MOSFET (PSGT-MOSFET) with a double-shield structure composed of a separated gate (SG) and a p-type shielding layer (P_shield) is proposed and investigated. The P_shield is positioned within the drift region, which can suppress the electric field peak at the bottom of the trench during the off state. This helps to prevent premature breakdown of the gate oxide layer. Additionally, the presence of P_shield enables the device to have adaptive voltage withstand characteristics. The SG can convert a portion of gate-to-drain capacitance (C _gd) into drain-to-source capacitance (C _ds), significantly reducing the gate-to-drain charge of the device. This improvement in charge distribution helps enhance the switching characteristics of the device. Later, the impact of the position and length of the P_shield on the breakdown voltage (BV) and specific on-resistance (R _{on_sp}) was studied. The influence of the position and length of the SG on gate charge (Q _gd) and BV was also investigated. Through TCAD simulations, the parameters of P_shield and SG were optimized. Compared to conventional GaN TG-MOSFET with the same structural parameters, the gate charge was reduced by 88%. In addition, this paper also discusses the principle of adaptive voltage withstand in PSGT-MOSFET.

中文翻译：

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通过双屏蔽结构实现自适应耐压的 GaN 沟槽 MOSFET

提出并研究了一种新型GaN沟槽栅极垂直MOSFET（PSGT-MOSFET），其具有由分离栅极（SG）和p型屏蔽层（P_shield）组成的双屏蔽结构。 P_shield位于漂移区内，可以抑制关断状态下沟槽底部的电场峰值。这有助于防止栅极氧化层过早击穿。此外，P_shield 的存在使器件具有自适应耐压特性。 SG 可以转换一部分栅漏电容（C _gd ) 转换为漏源电容 (C _ds），显着减少器件的栅漏电荷。电荷分布的这种改进有助于增强器件的开关特性。后来，P_shield的位置和长度对击穿电压（BV）和比导通电阻的影响（右 _{on_sp}）进行了研究。 SG的位置和长度对栅极电荷的影响（问 _gd ) 和 BV 也进行了研究。通过TCAD仿真，对P_shield和SG的参数进行了优化。与相同结构参数的传统GaN TG-MOSFET相比，栅极电荷减少了88%。此外，本文还讨论了PSGT-MOSFET的自适应耐压原理。