Zhang Yulei, Wang Xi, Liu Lechen, Ji Xuan, Hou Junhui, Pu Hongbin
Department of Electrical Engineering, Xi'an University of Technology, Xi'an 710048, China.
Xi'an Key Laboratory of Power Electronic Devices and High Efficiency Power Conversion, Xi'an 710048, China.
Micromachines (Basel). 2025 Jun 29;16(7):761. doi: 10.3390/mi16070761.
The impact-ionization-enhanced mechanism is introduced into a SiC light-triggered thyristor (LTT) to improve its switching speed under weak UV illumination. The effects of impact ionization on photogenerated carrier multiplication and the dynamic switching performance of the SiC LTT are investigated through TCAD simulation. The relationships between bias voltage, UV light intensity, and key dynamic parameters are analyzed. Simulation results indicate that when the bias voltage exceeds 14 kV, the device enters the avalanche multiplication regime, leading to a significant increase in photocurrent under a given UV intensity. As the bias voltage increases, the turn-on time of the thyristor first decreases, then saturates, and finally drops rapidly. Under UV illumination of 100 mW/cm, the turn-on time decreases from 10.1 μs at 1 kV to 0.85 μs at 18 kV, while the switching energy dissipation at 18 kV is only 1292.3 mJ/cm. These results demonstrate that the impact-ionization-enhanced effect substantially improves the switching performance of SiC LTTs.
将碰撞电离增强机制引入碳化硅光触发晶闸管（LTT）中，以提高其在弱紫外光照下的开关速度。通过TCAD模拟研究了碰撞电离对光生载流子倍增以及碳化硅LTT动态开关性能的影响。分析了偏置电压、紫外光强度和关键动态参数之间的关系。模拟结果表明，当偏置电压超过14 kV时，器件进入雪崩倍增状态，导致在给定紫外光强度下光电流显著增加。随着偏置电压的增加，晶闸管的开通时间先减小，然后饱和，最后迅速下降。在100 mW/cm的紫外光照下，开通时间从1 kV时的10.1 μs降至18 kV时的0.85 μs，而18 kV时的开关能量耗散仅为1292.3 mJ/cm。这些结果表明，碰撞电离增强效应显著提高了碳化硅LTT的开关性能。
