针对GaN功率器件研发中增强型、耐压、漏电等关键问题，进行 3 项研究：1. 提出对称极化掺杂增强型功率GaN HFET新机理与结构。含4项机理 ① 对称极化掺杂提高开态电流：Al组分的线性渐变产生极化效应，形成三维电子气，提升器件电子面密度并拓宽电子输运路径。② 空穴气实现增强型：利用空穴气阻断纵向沟道实现增强型，兼具高阈值电压和高输出电流。③ 极化结和源场板增强阻断耐压：正、负极化电荷构建极化结，调制电场分布；源、漏极位于栅极同侧并构成源极场板，提高耐压且缩小器件尺寸。④ MIS凹栅抑制漏电：MIS凹槽栅抑制泄漏电流，并增大栅压摆幅。新器件耐压达200 V，阈值电压达1 V，输出电流达15 A，导通电阻不超过30 mΩ。2. 开发对称极化掺杂外延生长和高质量栅介质生长技术。3. 研究缺陷引起漏电的物理机制，提出漏电抑制技术和可靠性加固技术。项目乃前沿性基础创新研究，具有实用价值。

In view of the key issues how to realize the enhancement mode (E-mode), high breakdown voltage (BV) and low leakage current in GaN power devices research, the following 3 items researches will be implemented: 1. Mechanism and novel structure of symmetrically polarization-doped E-mode power GaN HFET is proposed. Four novel mechanisms are included: ① The mechanism that the polarization-doped improves the output current is given as follows: The three-dimensional electron gas (3DEG) is induced in the linear variation doping AlGaN layer due to the polarization effect, which improves electron density and broadens the electron transport path. ② The mechanism that the hole gas realizes the E-mode is given as follows: Hole gas blocks the vertical channel and thus realizes the E-mode with a trench MIS gate. The proposed HFET maintains both high threshold voltage and large output current. ③ The mechanism that the polarization junction and source field plate enhance the BV is given as follows: Polarization junction formed by positive and negative polarization charges modulates the electric field distribution; and the source and drain locate at the same side of the gate and the source acts as a field plate, improving the BV and decreasing the device size; ④ The mechanism that the MIS recessed gate suppresses the leakage current is given as follows: the MIS recessed gate is used to suppress the leakage current and increase the gate voltage swing. The BV of the proposed HFET is more than 200 V, threshold voltage is at least 1 V, output current is more than 15 A and on-resistance is less than 30 mΩ. 2. The epitaxy technology of the back-to-back symmetrically polarization doping and high quality gate dielectric growth technique are developed. 3. The leakage current physics mechanism caused by defects are studied, and supressed-leakage current and the reliability reinforcement methods are developed accordingly. This project has frontier innovative significance and practical value.