摘要
提出了线性缓交SIGeHBT的基区滚越时间τb的解析模型,基于该模型研究了基区渡越时问的低温行为。研究发现,τb随温度的降低而迅速减小,虽然大的基区Ge组份级变有利于τb的减少,但对小的基区缓变的HBT,通过降低温度,也能使τb有较大的减小,改善其频率特性。
A base transit time analytical model for linearly graded SiGe base HBT is presented.Based on the model, the low temperature behavior of base transit time, τb, is studied. It is found that re decreases rapidly as the temperature is lowered. While a large base Ge fraction grading can be beneficial to the reduction of τb, for HBT's with small Ge fraction grading,τb can be significantly reduced by lowering temperature.
出处
《微电子学》
CAS
CSCD
1996年第3期201-204,共4页
Microelectronics
基金
国家教委博士点基金
关键词
异质结
双极晶体管
基区渡越时间
应变层
Semiconductor device
SiGe device
Strained layer
Heterojunction bipolar transistor
Base transit time