双极型晶体管在强电磁脉冲作用下的瞬态响应

 利用时域有限差分法，对双极型晶体管在强电磁脉冲作用下的瞬态响应进行了2维数值模拟，分析了器件烧毁过程中电场、电流密度、温度等参数的分布及变化情况，分别观察了低电压和高电压脉冲作用下烧毁过程中热点的形成过程，并得到了器件烧毁所需时间以及能量与脉冲电压幅度之间的关系。在电压脉冲较低时，烧毁点位于通道中靠近集电极的位置，当脉冲电压达到一定幅度的时候，由于发射极与集电极之间发生雪崩击穿，基极和发射极之间电势会抬高，从而引起基极和发射极之间的击穿，形成新的热点，并在电压幅度约高于100 V的情况下会率先达到烧毁温度。随着脉冲电压幅度的增高，晶体管烧毁所需时间呈负指数减少，而所需能量在55~100 V之间接近于线性增长，直到电压幅度约高于100 V时才开始减少。

Transient response of bipolar junction transistor under intense electromagnetic pulse

By using the finite-difference time-domain method in two-dimension,the transient response of BJT(bipolar junction transistor) under the high power electromagnetic pulse was simulated.The distribution and variation of the electronic field,current density,and the temperature in the transistor during the burnout of the device were obtained and analyzed.The formations of hot spots during the process under the pulse with low and high magnitude were observed.That how the time and energy needed for burnout depended on the magnitude of the pulse was also obtained.When the magnitude of the pulse is relatively low,the hot spot locates near the collector in the breakdown tunnel.When the magnitude of the pulse is sufficiently high,the voltage between the base and the emitter will become very large because of the breakdown between the emitter and collector.Thus a new hot spot occurs due to the breakdown between the base and the emitter,and it will reach the burnout tempereture when the magnitude is more than 100 V.With the increase of the magnitude,the time needed for burnout is decreasing exponentially,while the energy needed for burnout is increasing linearly with magnitude from 55 V to 100 V but decreasing with magnitude higher than about 100 V.