Si/SiGe异质结阴/阳极电势控制高速LIGBT新器件研究

Novel potential-adjusted high speed LIGBT with Si/SiGe heterojunction anode/cathode is proposed for the first time, its operating characteristics will be analyzed and verificated. With P Si/N+ SiGe heterojunction cathode, N Si/P+ SiGe heterojunction anode, and potential-adjusted extracting path as its special structures, the novel device has snapback suppressing, high current holding capability, and low conduction losses during on-state, has small tail current and low turn-off losses during turn-off-state, and has latchup suppressing capability due to lower injection ratios of Si/SiGe heterojunction emitters, which results high reliability under large current. The fundamental trade-off between the conduction losses (Von) and the turn-off losses (Eoff) is optimized, and the reliability under large current is improved. Based on band structures of Si/SiGe heterojunction, semiconductor transport theory, the mechanism of suppressing snapback and latchup phenomenons, turn-off characteristics of different driving circuits, and high temperature characteristics will be analyzed and verificated. The novel device concept and its performance analysis is the key important device model for the new generation of applied smart power integrated circuits design and SiGe process development.

首次提出Si/SiGe异质结阴/阳极电势控制高速LIGBT新器件，并对其工作特性进行建模分析和验证。采用P Si/N+ SiGe异质结阴极、N Si/P+ SiGe异质结阳极和电势控制抽出结构的LIGBT新器件，在导通态有效抑制Snapback现象，呈现高效电导调制效应，可以获得较小的通态功耗；在关断态减小尾部电流，可以获得较小的关断功耗；低的异质结发射极注入效率有效抑制Latchup现象，可以获得较高的大电流可靠性。新器件可以优化导通功耗和关断功耗之间的约束关系、提高大电流可靠性。利用Si/SiGe异质结能带结构、半导体输运理论对新器件进行建模分析和验证，解析Latchup现象和Snapback现象的抑制机理，分析不同激励条件下的瞬态特性，研究器件的高温特性。新器件的提出及其等效模型的建立为新一代实用性SiGe智能功率集成电路设计和工艺开发提供器件级理论与技术支撑。

本项目以优化LIGBT器件的导通功耗和关断功耗之间的约束关系、提高器件工作可靠性为主要研究目标，提出了高阻控制区复合阳极快速LIGBT新结构、自驱动阳极辅助栅快速LIGBT新结构及充当自驱动阳极辅助栅结构的超级势垒整流器新结构、异质结电势控制快速LIGBT新结构等功率器件新结构，并对所提出的功率器件新结构的工作特性进行了理论分析和仿真验证或者实验验证。采用P Si/N+ SiGe异质结阴极、N Si/P+ SiGe异质结阳极和电势控制抽出结构（包括高阻控制区和自驱动阳极辅助栅）的LIGBT新器件，在导通态有效抑制Snapback现象，呈现高效电导调制效应，获得较小的通态功耗；在关断态减小尾部电流，获得较小的关断功耗；低的异质结发射极注入效率有效抑制Latchup现象，获得较高的大电流可靠性。利用Si/SiGe异质结能带结构、半导体输运理论对新器件进行了理论分析和仿真验证，解析了Latchup现象和Snapback现象的抑制机理，分析了关断瞬态的电流变化特性，研究了器件的高温特性。新器件结构的提出及其工作特性的分析验证发展和丰富了高速LIGBT电势控制理论、有益于新一代实用性SiGe智能功率集成电路设计和工艺开发，并且通过对充当自驱动阳极辅助栅快速LIGBT新结构的自驱动阳极辅助栅结构的超级势垒整流器的详细研究，提出了一类全新的肖特基接触超级势垒整流器新结构，其在100V以下的整流应用中具有很好的竞争优势。