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载流子通过窄基区的硅双极晶体管的基极和集电极空间电荷区的输运,是用输运过程的Monte Carlo模拟的方法研究的。所得到的基区内载流子浓度比由一般的漂移-扩散方程所确定的要大,而且载流子渡越时间也相应地增加。在集电极空间电荷区的开始端的电场突然地增加到很大值时,观察到载流子平均速度异常地高。而后者要衰减到饱和速度,其时间常数与电场及各种动量弛豫时间有关。该现象是一个非平衡效应,不能用漂移-扩散方程计算,但是它对集电极渡越时间却是一个有限的影响因素。
The transport of carriers through the base of the narrow base silicon bipolar transistor and the collector space charge region is studied using the Monte Carlo simulation of the transport process. The resulting carrier concentration in the base region is larger than that determined by the general drift-diffusion equation, and the carrier transit time increases accordingly. When the electric field at the beginning of the collector space charge region suddenly increases to a large value, it is observed that the average carrier speed is abnormally high. While the latter decays to saturation speed. The time constant is related to the electric field and various momentum relaxation times. This phenomenon is a non-equilibrium effect that can not be calculated using the drift-diffusion equation, but it has a limited effect on the collector transit time.