异质结耗尽层基区侧复合对突变HBT重要性分析

An Analysis of the Importance of Recombination in the Base Side of the Emitter-Base SCR in Abrupt HBTs

基于热场发射-扩散载流子输运模型,在电流连续性方程中包含异质结(E-B结)耗尽层基区侧复合电流的前提下,推导出了描述突变HBT电流特性的新解析方程.在此基础上,探讨了对E-B结耗尽层基区侧复合电流各不同考虑情况下的HBT电流计算结果的差异程度.结果表明:在较高集电极电流密度处,E-B结耗尽层基区侧的复合电流很重要;此外,在电流连续性方程中包含E-B结耗尽层基区侧的复合电流,这在更高集电极电流密度处也是必要的.

In this paper,we investigate the importance of including recombination in the base side of the emitter-base space-chargeregion（SCR） in the current continuity equation when computing the current gain in abrupt HBTs, Based on the thermionic field-diffusion model, new analytical expressions for the terminal currents are proposed. These new expressions are more accurate in predicting the performance of HBTs operating at high collector current density because of the inclusion of the recombination currents in the current continuity equation.