宽温区高热稳定性SiGe HBT的基区优化设计  

Design and Optimization of Base-Profile for the Thermal Stability of SiGe HBT Over Wide Temperature Range

作　　者：付强[1] 张万荣 金冬月[1] 赵彦晓[1] 张良浩[1] 

机构地区：[1]北京工业大学电子信息与控制工程学院,北京100124

出　　处：《北京工业大学学报》2015年第5期686-692,共7页Journal of Beijing University of Technology

基　　金：国家自然科学基金资助项目(61006059);北京市自然科学基金资助项目(4142007);北京市教委科技发展计划项目(KM200910005001)

摘　　要：为了提高SiGe异质结双极型晶体管(heterojunction bipolar transistors,HBTs)电流增益和特征频率温度热稳定性,首先研究基区杂质浓度分布对基区Ge组分分布为矩形分布的SiGe HBT电流增益和特征频率温度敏感性的影响,基区峰值浓度位置逐渐向集电极靠近可削弱器件的电流增益和特征频率对温度变化的敏感性.随后在选取基区峰值杂质浓度靠近集电极处分布的基础上,研究基区Ge组分分布对SiGe HBT的电流增益和特征频率温度敏感性的影响,减小基区发射极侧Ge组分和增加基区Ge组分梯度可削弱SiGe HBT的电流增益对温度变化的敏感性,增加基区发射极侧Ge组分的摩尔分数和减小基区Ge组分梯度可削弱SiGe HBT的特征频率对温度变化的敏感性.在此研究结果基础上,提出了一种新型基区Ge组分分布的SiGe HBT,它拥有较高的电流增益和特征频率且其温度敏感性较弱.To improve the thermal stability of curvent gain β and cut-off frequency f_T in SiGe heterojunction bipolur transistors（HBTs）,the impacts of doping profile in the base of SiGe HBT with the box Ge profile on the temperature sensitivity of current gain β and cut-off frequency f_T are investigated firstly.It can be found that with the doping peak concentration in the base gradually approaching to the collector,β and f_T of HBT decrease slowly as temperature increases.Then the impacts of Ge profile across the base of SiGe HBT with the base peak concentration approaching to the collector on the temperature sensitivity of current gain β and cut-off frequency f_T are investigated.It can be found that reducing Ge fraction at the emitter end of the base and increasing grading of the Ge across the base can weaken the sensitivity of β to temperature,and reducing grading of the Ge across the base and increasing Ge fraction at the emitter end of the base can weaken the sensitivity of f_T to temperature.Based on these results,a novel segmented step box（SSB） Ge profile is proposed,which possesses modest β and f_T,and weak temperature sensitivity of current gain and cut-off frequency.

关 键 词：SiGe异质结双极型晶体管(HBTs) 温度敏感性 杂质浓度分布 GE组分分布 

分 类 号：TN385[电子电信—物理电子学]