半导体断路开关纳秒脉冲截断机理研究

Semiconductor opening switch (SOS) is a key device of all solid-state high power-high repetition rate pulsed power source. The interruption mechanisms of the SOS under high current-injection conditions and its theoretical description is the scientific problems to be solved urgently. This project first to establish a stable two-dimensional circuit-fluid coupled numerical model of the SOS, the improved carrier mobility/diffusion model and the excess carrier generation/recombination model in strong electric field. Through theoretical analysis and circuit-fluid coupled numerical simulation, the nanosecond pulse interruption process and its evolution is then studied. And the existing SOS structure and the external circuit pump parameters are optimized with one-dimensional, two-dimensional simulation and experiments. Finally the two-dimensional effect on SOS, which leads to the generation of the nanosecond/sub-nanosecond pulse for the formation of ultra-wideband electromagnetic radiation, is investigated with two-dimensional simulations. The project is important for improving the performance of all-solid-state high power-high repetition rate pulsed power source, and promoting the development and application of pulsed power technology in the field of high power microwave, high current accelerator et. al. It is also has important theoretical significance and practical value to explore the application of SOS in the repetition rate ultra-wideband electromagnetic radiation fields.

半导体断路开关 (SOS) 是全固态高功率高重复频率脉冲功率源的关键器件，其强流注入条件下的截断机理和理论描述是当前亟需解决的科学问题。本项目首先建立稳定的SOS二维电路-流体耦合数值模型、强场条件下的载流子迁移/扩散模型和过剩载流子的产生/复合模型，通过理论分析和电路-流体耦合数值模拟，研究SOS的纳秒脉冲截断机理和截断过程演变规律；结合一维、二维电路-流体耦合数值模拟和实验，对现有SOS结构和外电路泵浦参数进行优化设计；通过二维电路-流体耦合数值模拟，对SOS二维效应产生纳秒/亚纳秒脉冲从而形成超宽带电磁辐射的机理和物理过程进行探索和分析。本项目对于提高全固态高功率高重复频率脉冲功率源的性能水平、推动脉冲功率技术在高功率微波、强流加速器等领域的发展和应用、探索SOS在重复频率超宽带电磁辐射源领域的应用具有重要的理论意义和实用价值。

半导体断路开关 (SOS) 是全固态高功率高重复频率脉冲功率源和超宽带辐射源的关键器件，其强流注入条件下的截断机理的理论描述和数值建模是当前亟需解决的科学问题。本项目在对半导体断路开关导通和截断机理理论分析的基础上，建立了SOS一维和二维电路-流体耦合模型和强流条件下的载流子迁移/扩散模型和过剩载流子的产生/复合模型，并编写了相应的SOS二维电路-流体模拟程序； 结合一维、二维电路-流体耦合数值模拟和实验，对SOS截断过程、截断特性的参数影响规律开展研究。首先分析了SOS的截断过程，发现SOS截断开始的位置在过去研究结果中出现差异的原因是器件的掺杂分布不同，但最终的截断区域都稳定在结附近。然后对SOS器件结构和外电路泵浦参数进行了优化设计，得到了截断时间为几百皮秒量级的输出脉冲，初步实现了超宽带电磁辐射的要求。此外，本项目除对SOS截断机理和实现亚纳秒截断的研究之外，还将研究范围进行了延伸，对相似的半导体结型器件如漂移阶跃恢复二极管(DSRD)的截断机理进行了分析。采用二维电路-流体耦合模型对其导通和截断过程进行了模拟，发现DSRD的截断过程分为缓慢截断和快速截断，并获得其截断特性与结构参数、电路参数的关系。本项目对于提高全固态高功率高重复频率脉冲功率源的性能水平、推动脉冲功率技术在高功率微波、强流加速器等领域的发展和应用、探索SOS 在重复频率超宽带电磁辐射源领域的应用具有重要的理论意义和实用价值。