HEMT器件电磁脉冲毁伤机理仿真分析及试验研究

Simulation and Experimental Study on Damage Mechanism of Electromagnetic Pulse of HEMT Device

以强电磁脉冲为典型代表的复杂电磁环境对雷达前端关键模块与器件的可靠性不断构成威胁。本文对雷达前端电路中低噪声放大器的关键器件——GaAs HEMT进行了强电磁脉冲效应仿真研究与试验验证。利用仿真软件构建了GaAs HEMT的二维热电模型,并对器件栅极注入强电磁脉冲的情况进行了仿真,研究发现,该注入条件下器件内部峰值温度呈现周期性的上升-下降-上升-下降趋势,最终达到GaAs的熔点温度,导致器件烧毁,烧毁位置在栅极下方偏向源极的位置。通过对低噪声放大器芯片进行注入实验和剖片分析,在TEM显微镜下观察到GaAs HEMT器件栅极下方靠近源极的区域有明显烧毁,与仿真结果相符。通过对仿真数据的处理和拟合,总结了器件烧毁功率阈值和能量阈值与注入微波脉宽的关系,得出器件烧毁的功率阈值随着脉宽的增大而减小,能量阈值随着脉宽的增大而增大,与经验公式相符。

The complex electromagnetic environment represented by electromagnetic pulses is a constant threat to the reliability of key modules and devices in the radar front end.In this paper,the simulation and experimental verification of the strong electromagnetic pulse effect are performed for the GaAs HEMT,which is a key component of the low-noise amplifier in the radar front-end circuit.The two-dimensional thermoelectric model of GaAs HEMT is constructed by using simulation software,and the injection of electromagnetic pulse to the gate of the device is simulated.It is found that the peak temperature inside the device exhibits a periodic rise-fall-rise-fall trend under the injection condition,and the final temperature will reach the melting point of GaAs,leading to burnout,which is located below the gate closed to the source.Through the injection experiment and the slice analysis of the low-noise amplifier chip,it is observed that the area near the source of the gate of the GaAs HEMT device is burnt under the TEM microscope,which is in good agreement with the simulation results.Through the processing and fitting of the simulation data,the relationship between burnout power threshold and injection microwave pulse width and the relationship between burnout energy threshold and injection microwave pulse width are analyzed.It can be concluded that the power threshold of the device burnout decreases with the increase of the pulse width,and the energy threshold increases with increasing pulse width,which is consistent with empirical formulas.