超高压碳化硅光触发晶闸管关键技术研究

In view of the fact that the high-voltage silicon Light Triggered Thyristor (LTT) has approached the physical limitation of silicon material. In order to improve the sensitivity for the purpose of the realization of SiC LTT triggered by the UV LED light source basing on the characteristics of 4H-SiC material and the operating principles of LTT, A novel structure of SiC Ultra-high Voltage (UHV) LTT with multistage amplifying gates and the new composite junction termination which have combined circular-arc mesa structure with three-zone junction termination extension (JTE) modulated by charges is proposed. The theoretical analyses and experiments will be carried out in this study. In this project, the key models of physical and analysis will be established by considering parameters affecting the photoelectric characteristic and the temperature characteristic to investigate the operation mechanism and to optimize the device structure by means of numerical simulation, and thereby improve the theoretical research of operation mechanism of the device. The theoretical models of the effective charge-modulated for the UHV junction termination will be established and improved by investigating the process robustness of the new composite junction termination. A large number of the process experiments will be done to develop circular-arc mesa process technology and to optimize RIE etching technology and surface passivation technology. Then, the technological process, the layouts and photo-masks will be designed and produced respectively for tape-out and experimental verification of the operation mechanism of the device. Furthermore, the device process and implementation scheme will be verified and established by testing and analyzing of the device..In a word, Once succeeded, the research results of this project would provide the theoretical references and technical approach for the design, and manufacture and application of UHV SiC LTT for our country.

鉴于高压Si光触发晶闸管(LTT)的特性已逼近其材料的物理极限。本项目基于4H-SiC材料特性和LTT工作原理，以具有圆弧台面与电荷调制功能的3区JTE新型复合结构为结终端，以提高灵敏度，实现UV LED光源触发为目标，提出一种具有多级放大门极的超高压SiC LTT新结构。并拟从理论和实验两方面对其展开研究。具体包括建立影响光电特性、温度特性等关键物理参数及特性分析模型，基于数值仿真，对器件机理和器件结构进行分析与优化设计，完善器件工作机理的理论研究。研究新型复合结终端的工艺鲁棒性，建立并完善超高压结终端的有效电荷调制理论模型。通过工艺实验，开发SiC圆弧台面技术，优化RIE刻蚀和表面钝化工艺。设计工艺流程，制版并进行流片验证，通过测试分析，验证并完善超高压SiC LTT的理论，确立器件工艺实施方案。研究结果为我国超高压SiC LTT的设计、制造及应用提供理论指导和技术途径。