针对GaN电力电子器件中增强型、耐压、漏电等关键问题，进行以下创新研究：1.提出空穴气增强型高压GaN HEMT机理与新结构。构建GaN/AlGaN /GaN双异质结和纵向沟道结构，形成由2DHG和2DEG构成的极化结。机理含①空穴气阻断纵向沟道实现增强型，器件兼具高阈值电压和高输出电流。②极化结和源极场板提高器件耐压。极化结辅助耗尽漂移区并调制电场分布；源、漏极位于栅极同侧并构成源场板，提高耐压且缩小器件尺寸。③MIS凹槽栅抑制泄漏电流并增大栅压摆幅。新器件阈值电压达1.5-3.0V，输出电流大于400mA/mm，耐压较相同尺寸的常规GaN HEMT提高30%以上。2.建立阈值电压电荷控制模型。基于极化理论和能带工程，通过调制2DHG浓度而改变异质结能带结构，实现对阈值电压控制。3.研制所提GaN HEMT，分析失效机制，探索漏电抑制技术。本项目研究具有前沿基础创新性和实用价值。

In view of the key issues of enhancement mode (E-mode), breakdown voltage (BV) and leakage current in GaN power electronics devices, the following innovative researches will be implemented: 1. Mechanism and Novel structure of Hole Gas Enhancement-mode High-Voltage GaN HEMT is proposed. The GaN/AlGaN/GaN dual-heterojunction and a vertical channel are designed. The 2DHG and 2DEG are introduced in the dual-heterojunction, and the polarization junction is formed by 2DHG and 2DEG. The Novel Mechanisms of the proposed include: ①2DHG blocks the vertical channel to realize the E-mode. The proposed HEMT maintains high threshold voltage and large output current; ②The BV is improved by polarization junction and the source field plate. Polarization junction has the assisted depletion effect on the drift region and modulates the electric field distribution in the drift region; The source and drain locate at the same side of the gate and the source act as a field plate, improving the BV and decreasing the device size; ③The MIS recessed gate is used to suppress the leakage current and increase the gate voltage swing. The threshold voltage of 1.5V-3V for the novel HEMT is designed and output current is more than 400mA/mm. Compared with conventional HEMT, the proposed HEMT increases the BV by more than 30%. 2. The charge-controlled model for threshold voltage is presented. Based on the polarization theory and the energy band engineering, the energy band structure is changed by modulating the 2DHG concentration, and thus the threshold voltage is controlled. 3. The proposed GaN HEMT is to be fabricated. The device failure mechanism will be studied and the leakage-suppressed technology is explored. This project has frontier innovative significance and practical value.