多晶硅发射区晶体管（PET）温度特性的解析理论分析

Analytical Theory for Temperature Characteristics of Polysilicon Emitter Transistors (PET)

本文在已提出的综合解析模型基础上，引入各相关参数特别是多晶－单晶之间的界面态俘获截面与温度关系的实验结果，给出了分析ＰＥＴ电流增益与温度关系的解析理论．以此为基础，详细分析了少子在多晶－单晶之间的界面氧化层两边界面态上的复合和少于以热发射的方式跃过杂质分凝和界面氧化层电荷形成的势垒并隧穿界面氧化层两种机理对ＰＥＴ电流增益随温度变化的影响，首次成功地把ＨＦ器件电流增益在高温区呈现出比普通金属接触晶体管温度系数大的实验结果归因于少子在界面氧化层两边的复合以及俘获截面与温度的关系σｐ．∞Ｔ－２．７，分析预示了界面氧化层破裂对ＲＣＡ器件电流增益温度特性的影响，得到了对获得低温度系数ＰＥＴ有益的结论．

Abstract Based on the comprehensive analytical model published,an analytical theory relating PET's current gain to temperature is proposed by introducing concerning ters, particularly capture cross section of inter facial state at polysilicon-silicon interface,as a function of temperature. By using. this theory, the effects of two transport mechanisms of minority carrier recombination at bath sides of the inter facial oxide, and minority carrier over impurity segregation and inter facial oxide charge potential barrier by thermionic emission and tunneling through the inter facial oxide,on PET's current gain variation in temperature are analyzed deeply. It fis explained successfully for the'first time that HF device current gain shows more sensitive to temperature than the metal contacted conventional transistor at a higher temperature by the minority carrier recombination at both sides of the inter facial oxide and relation between capture cross section and temperature,σ∞T-2.7. The influence of the interfacial oxide break on RCA device temperature characteristics of current gain is predicted. Some conclusions advantageous to obtaining PET with the lower temperature sensitivity of current gain are presented.