摘要
低温下hFE主要决定于发射效率γ和集电区倍增因子M．影响γ的是禁带收缩和基区费米能级．M则主要由中性杂质被碰撞电离而造成的电流倍增效应决定，并且这是一种自抑制效应，以上观点与实验结果基本相符合。
The current gain hFE is mainly decided by emitting efficiency γand the multiplication factor M of collective region at low temperature. The γis affected by bandgap contraction and the fermi energy level of base region. The factor M is mainly decided by current multiplication effect formed by colliding ionization of neutral impurities, and this is a self-restrained effect. The above theory is basically consistent with the experiment results.
关键词
双极晶体管
低温hFE
发射效率
集电区倍增因子
Electron emission
Gain control
Low temperature phenomena
Semiconducting gallium
Semiconducting silicon
