HBT的PN结偏移效应

EFFECTS OF DISPLACED P-N JUNCTION OF HBT

采用流体动力学输运模型详细分析了发射区PN结偏移对AlGaAs／GaAsHBT器件性能的影响，提出了器件优化设计的原则．在中等和小的偏压下为了提高β，PN结应向宽禁带层偏移，而为了得到大电流下大的电流放大倍数则应采用PN结与异质结对准的结构．

The Hydrodynamic Transport Model is used to simulate the effects of displacemeilt of PN junctions of HBT. The electric characteristics are shown to be drastically altered due to changes in the potential profiles and in recombination in both neutral base and space - charge region of the emitter. The effects of a small displacement of the PN junctions from emitter - base are examined and results for current gains and cutoff frequencies are given.