激光二极管触发光导开关实验研究

介绍了利用大功率半导体激光二极管触发3 mm间隙GaAs光导开关、产生非线性电脉冲输出的实验，激光二极管输出功率为70 W，上升前沿约20 ns，脉冲半高宽（FWHM）约40 ns。随着开关两端偏置场强增加，输出电压也线性增加，当偏置场强超过一定阈值，增至约2.53 kV/mm时，经过一个较小的电压峰值和时间延迟后，输出电压急剧增加，产生雪崩现象。实验结果表明:GaAs开关非线性输出的产生与载流子聚集和碰撞电离有关，偏置电场的提高增加了开关芯片中载流子聚集数量，加剧了碰撞离化程度，从而使开关从线性模式进入雪崩模式。

Experimental research on GaAs photoconductive semiconductor switches triggered by laser diode

This paper introduces an experiment of 3 mm-gap GaAs photoconductive semiconductor switch (PCSS) triggered by laser diode, which produces nonlinear output on 600 Ω load. The peak power of laser diode is 70 W, and its output rise-time and duration (FWHM) are 20 and 40 ns, respectively. Along with the bias electric field enhancement, the output voltage increases linearly; when the bias electric field exceeds the threshold, about 2.53 kV/mm, the output voltage increases rapidly after a small peak and delay, and the avalanche occurs. Experiment results indicate that the production of nonlinear output has relation to carrier accumulation and impact ionization in GaAs chip; the enhancement of bias electric field increases the number of collective carriers, the degree of impact ionization, and thus accelerate the switch’s turn into avalanche mode.