低温多晶硅发射极晶体管电流增益和截止频率的解析模型

The Analytical Model of Current Gain and Cutoff Frequency of Polysilicon Emitter Transistors for Low Temperature Operation

本文综合考虑了多晶硅发射极的载流子输运障碍，界面氧化物遂穿、晶粒间界杂质分凝和界面能带弯曲等因素，以及禁带变窄效应、低温下的载流子冻析效应和浅能级补偿杂质陷阱效应，建立了低温多晶硅发射极晶体管电流增益和截止频率的解析模型，对电流增益和截止频率的温度关系进行了理论分析并与３００Ｋ和７７Ｋ下的实测结果进行了比较。

An analytical model of current gain and cutoff frequency of polysilicon emitter bipolar transistors for low temperature operation has been derived in consideration of 'grain boundary mobility medel'.,'oxide tunneling medel','segregation model'and 'band-bending'at polysilicon-silicon interface,and bandgap narrowing,carrier freezeout and trapping effect of shallow level impurities at low temperature.The temperature dependence of current gain and cutoff freqnency of this kind of transistor is analyzed theoretically,and the results are compared with experimental data at 300K and 77K.