激光能量分布对GaN基光导开关导通特性的影响

Influence of laser spot energy distribution on the on-state performance of GaN-based photoconductive switches

摘要: 光斑是影响光导开关导通特性的重要因素之一。探索了激光能量分布对光导开关输出特性的影响，分别采用高斯光和平顶光对同一GaN光导开关导通特性进行了对比测试。结果表明，由于平顶光具有更均匀的能量分布，相比于高斯光触发，在相同外加偏置电压（800 V）下，电压转换效率提升了6.8%。在激光能量为500 μJ时的平顶光触发下进行了加压测试，最大峰值输出电压为4550 V，此时输出功率达到414 kW，上升时间为420 ps，下降时间为5 ns，导通电阻为13.7 Ω。

Abstract: The beam spot is one of the important factors affecting the on-state performance of photoconductive switches. The on-state performance of the GaN photoconductive switch has been tested under the triggering of Gaussian beam and flat-top beam. As the energy uniformity of flat-top beam is better than that of Gaussian beam, the results show that the voltage conversion efficiency is increased by 6.8% under the same applied bias voltage (800 V), Triggered by flat-top beam at a laser energy of 500 μJ, GaN PCSS shows a maximum peak output voltage of 4550 V, at the same time the output power reaches 414 kW and the conduction is 13.7 Ω. The output waveform has a rise time of 420 ps and a fall time of 5 ns.