新型高阈值电压GaN电力电子器件模型与关键技术研究

针对GaN功率器件如何实现高阈值电压、高可靠性及高耐压的关键科学问题，本课题创新研究包括：2项模型与技术、2类新结构、成套制备工艺及增强型GaN器件的驱动集成电路。①提出GaN器件阈值电压调控模型和精确控制技术，为高阈值电压器件提供理论依据；②研究栅极失效和动态电阻衰退的物理机理，建立动态电阻模型，获得可靠性加固技术；③提出并研制具有新型终端结构的复合栅增强型GaN功率器件和多极化增强型GaN功率器件，耐压达600V-900V，阈值电压高于2V，输出电流高于350mA/mm，实现低泄漏电流与高可靠性；④开发高阈值电压、高可靠性GaN器件成套工艺，推动GaN增强型器件产业化；⑤设计高频、高效率和高可靠性的GaN增强型器件驱动集成电路，突破GaN器件阈值电压低且栅易击穿的应用瓶颈。本项目研究为GaN功率器件推向更高电压、更低功耗及更可靠奠定坚实基础，具有重要科学意义和实用价值。

To address the key scientific problems of how to realize high threshold voltage, high reliability and high breakdown voltage (BV) for GaN power electronics devices, this project launches the following innovative research: two models and technologies, two types of new structures, design of complete fabrication processes and driving integrated circuit of enhanced mode GaN devices. (1) The modulation model and accuracy control technology of threshold voltage for GaN devices are proposed to provide a theoretical guidance for high threshold voltage. (2) The physical mechanisms of gate failure and dynamic resistance degradation are studied and then the dynamic resistance model is established, based on which the reliability reinforcement technologies are obtained; (3) Two types of enhancement-mode (E-mode) GaN power devices are proposed and analyzed by simulation and experiments. One is trench type MIS HEMT with novel termination structure and the other is MIS HEMT with multi-polarization structure. The proposed new E-mode GaN devices achieve a low leakage current and high reliability, with breakdown voltage among 600V~900V, threshold voltage over 2V and current density over 350mA/mm. (4) The complete fabrication technologies and the industrialization are developed and promoted for GaN devices with high threshold voltage and high reliability. (5) A high frequency, high efficiency and high reliability gate driving integrated circuit for E-mode GaN devices are developed, which breaks through the application bottleneck of low threshold voltage and gate breakdown for GaN devices. The research of this project lays a solid foundation for GaN power devices to achieve higher voltage, lower power consumption and better reliability. This project owns important scientific significance and practical values.