外延双极晶体管基区表面电流的模型及应用

The model for the base surface current in epitaxial bipolar transistors and its applications

少数载流子在Ｓｉ－ＳｉＯ＿２界面的复合对双极器件的影响很大。文中通过对采用ＳｉＯ＿２膜和ＳｉＯ＿２－Ｓｉ＿３Ｎ＿４双层膜一次钝化的电容（ＭＯＳ和ＭＮＯＳ）和栅控外延ＮＰＮ晶体管表面电特性的研究，发现ＳｉＯ＿２－Ｓｉ＿３Ｎ＿４一次钝化膜能减小基区表面电流。文中建立了外延双极晶体管基区表面电流随栅区（或基区表面电势）变化的理论模型，该模型成功地解释了栅控外延双极晶体管的基区表面电流随栅压变化的实验曲线，从而为器件的计算机模拟提供了更加精确的模型．

The recombination of minority carriers at Si-SiO_2 interface has a great effect on bipolar de-vices. In this paper , the surface electrical property of capacitors(MOS or MNOS ) and gate-controlled NPN transistors which are passivated alternatively by SiO_2 and SiO_2-Si_3N_4 films arestudied and it is found that the SiO_2-Si_3N_4 dual dielectrica films can reduce the surface currentin the base region. An improved theoretical model of the base surface current vs. surface po-tential or gate voltage is set up on the basis of the work of Ref.[3] for epitaxial bipolar transis-tors. The model successfully explains the experimental results of the variation of the base sur-face current of the gate-controlled epitaxial bipolar NPN transistors with the gate voltage andprovides a more accurate model for the computer simulation of the devices.