SiGe HBT异质结势垒高度物理模型研究

Modeling of Heterojunction Barrier Effects in SiGe HBT Operating at High Current

基于SiGe HBT异质结势垒效应(HBE)产生的物理机制,综合考虑Ge引入集电区和大电流下电流感应基区中少子浓度对空穴浓度的影响,建立了异质结势垒高度解析模型。结果表明,将Ge引入集电区可有效地推迟HBE发生;同时,考虑少子浓度的影响,势垒高度具有明显的饱和趋势,峰值约为0.07 eV。

Abstract： Based on the physical mechanism of heteroiunction barrier effects （HBE） in SiGe HBT＇s, an analytical model of barrier height of Si/SiGe heterojunction is studied with effects of different Ge profile in collector and the concentration of electrons in base region on the concentration of holes at high current taken into consideration. Results show that Ge introduced into the collector can delay HBE. Meanwhile, the proposed model exhibits apparent saturation trend of barrier height at 0. 07 eV when effects of minority carrier concentration are taken into consideration.