可双向阻断高性能增强型GaN基栅-漏复合场板功率器件研究

Nowadays, the developments of the power semiconductor devices with high performance and low power losses, so as to effectivelly improve the performance of the power conversion and control system, have been one of the effective approaches to improve the utilization rate of power energy, to save energy and to reduce energy crisis as well as environmental pollution. A kind of novel field-plated power device with bidirectional blocking ability, named as normally off GaN-based power device with gate-drain compound field-plates is studied in this project. And the device mechanisms and implementation methods are explored. Aiming at the three big key scientific problems needed to be solved, the physical mechanisms of defects bahavior and their impact are investigated in GaN-based power devices. The physical essence of the realization of normally off devices with polarization neutralization technique, and the physical mechanisms of the Schottky-mesh-Ohmic drain under high electric field are analyzed. And the device theoretical models with effectiveness and practice are establised. Then, the modulation mechanisms of the field-plate and the implementation mehtods of devices are explored. Finally, the device samples with high performance are obtained, and the studies of device practical applications are carried out. By the study of this project, the key factors which restricts the performance improvements in the current devcies with high voltage and high power, will be revealed. And a kind of high performance normally off GaN-based power device using gate-drain compound field-plates which features good manufacturability, good bidirectional blocking performance, great application potential and independent intellectual property rights will be provided. Moreover, contributions of the theories and techniques will be provided for the exploration of novel power devices.

当前，研发高性能、低损耗的半导体功率器件，有效提升功率转换和控制系统的性能，是提高电能利用率、节约能源、缓解能源危机和环境污染问题的有效途径之一。本课题旨在研究一种可双向阻断的新型场板功率器件——增强型GaN基栅-漏复合场板功率器件，开展器件机理和实现方法的探索。围绕需解决的三大关键科学问题，开展GaN基功率器件中缺陷行为及其影响的物理机制研究；剖析极化中和技术实现增强型器件的物理本质及高场下肖特基-网状欧姆漏极的物理机制；构建有效且符合实际的器件理论模型，探索增强型GaN基栅-漏复合场板功率器件的场板调制机理及实现方法；最后获得高性能器件样品，并进行器件应用研究。通过本课题研究，将揭示制约当前GaN基高压大功率器件性能提升的关键因素，提供一种可制造性强、双向阻断特性好、应用潜力大的具有自主知识产权的高性能增强型GaN基栅-漏复合场板功率器件，并为我国新型功率器件的探索提供理论和技术支撑。

当前，研发高性能、低损耗的半导体功率器件，有效提升功率转换和控制系统的性能，是提高电能利用率、节约能源、缓解能源危机和环境污染问题的有效途径之一。本项目旨在研究一种可双向阻断的新型场板功率器件——增强型GaN基栅-漏复合场板功率器件，开展器件机理和实现方法的探索。本项目主要研究包括器件理论研究和器件实验研究两大部分，在理论研究方面涵盖GaN 基功率器件中缺陷行为物理模型研究、GaN基功率器件理论模型研究、极化中和技术实现增强型GaN基功率器件的机理研究、大功率AlGaN/GaN高电子迁移率晶体管热特性研究、可双向阻断GaN 基功率器件的理论模型及工作机理研究等；在实验研究方面涵盖GaN基栅-漏复合场板功率器件结构和版图设计、增强型GaN基功率器件的实现机理及方法研究、网状欧姆接触改善器件接触电阻研究、GaN 基栅-漏复合场板功率器件实验研究等。最后，成功实现了增强型GaN基栅-漏复合场板功率器件。通过本项目研究，揭示了制约GaN基高压大功率器件性能提升的关键因素，提供了一种可制造性强、双向阻断特性好、应用潜力大的具有自主知识产权的高性能增强型GaN基栅-漏复合场板功率器件，将为我国新型功率器件的进一步探索提供重要的理论和技术支撑。