Si基GaN增强型功率开关器件是近年来国际学术界和工业界的研究热点，凭借其低成本、高性能的优越特性有望成为下一代高效、高速电力电子的理想候选技术之一。本申请以研发高阈值电压（VTH ）Si基GaN增强型高压功率开关器件为目标，针对阈值电压调控基础科学理论和器件关键制备技术开展创新研究。1）基于AlGaN/GaN异质结电荷分布建立电荷控制阈值电压调控模型，阐明电荷、能带与阈值电压的本质关系，揭示其调控机理；2）研究界面电荷微观起源，开发有效抑制界面电荷的III-Nitride表面等离子体处理技术和栅介质热处理技术，实现VTH 的大范围调控（>10 V）；3）提出F-离子埋层半凹栅增强型器件新结构，利用半凹栅和F-离子埋层对VTH 的双重调控，研制出高性能Si基GaN增强型功率开关器件，实现VTH >6 V，ΔVTH<0.5 V，击穿电压超过1000 V，导通电阻小于5 mΩ•cm2。

GaN-on-Si Enhancement-mode (E-mode) power switching devices is a research hot topic in both academia and industries in recent years. Due to its superior properties of low cost and high device performance the GaN-on-Si E-mode power device is a promising candidate for next generation high efficiency and high speed power electronics. In purpose of fabricating high performance GaN-on-Si E-mode power devices with high threshold voltage (VTH) and high breakdown voltage, this project will carry out intensive study on the fundamental scientific theory of threshold voltage modulation and the corresponding key device fabrication technologies. 1) Based on the charge (e.g. polarization charge, interface states, fixed interface charge, doping charge) distribution of AlGaN/GaN heterojunction the Charge-control Threshold-Voltage Modulation (CTVM) model will be developed, which reveals the essential interaction of charges, energy band and VTH as well as the mechanism of threshold voltage modulation; 2) The origin of the interface charges will be investigated. Accordingly, the III-Nitride surface pre-treatment techniques and post gate dielectric thermal treatment technology for an effective suppression of the interface charges will be developed to achieve a large modulation range of the VTH (e.g. >10 V). 3) A novel E-mode device structure featuring a BUried-Fluorine Shallow-Trench gate is proposed, in which the dual modulation of VTH is achieved by using the shallow-trench gate and the buried F- layer. The fabricated E-mode GaN-on-Si power devices are expected to deliver a VTH higher than +6 V, a ΔVTH lower than 0.5 V, a breakdown voltage over 1000 V and a Ron lower than 5 mΩ•cm2.