摘要
设计了一种新结构InP/InGaAs/InP双异质结双极晶体管(DHBT),在集电区与基区之间插入n+-InP层,以降低集电结的导带势垒尖峰,克服电流阻挡效应.采用基于热场发射和连续性方程的发射透射模型,计算了n+-InP插入层掺杂浓度和厚度对InP/InGaAs/InPDHBT集电结导带有效势垒高度和I-V特性的影响.结果表明,当n+-InP插入层掺杂浓度为3×1019cm-3、厚度为3nm时,可以获得较好的器件特性.采用气态源分子束外延(GSMBE)技术成功地生长出InP/InGaAs/InPDHBT结构材料.器件研制结果表明,所设计的DHBT材料结构能有效降低集电结的导带势垒尖峰,显著改善器件的输出特性.
A novel InP/InOaAs/InP double heterojunction bipolar transistor (DHBT) structure is designed,in which a thin heavily doped n^+-InP layer between the base and the collector is used to eliminate the energy spike at the B-C junction and overcome the electron blocking effect. The dependence of the effective barrier spike at the B-C junction and the I-V characteristics of the DHBT on the thickness and doping density of the n^+-InP composite collector are analyzed theoretically. The results show that the device performance is optimal when the doping density is 3 × 10^19cm^-3 and the thickness is 3nm for the n^+-InP composite collector. The InP/InGaAs/InP DHBTs with composite doping collector are grown by gas source molecular beam epitaxy (GSMBE). The DC characteristics of the devices demonstrate that the InP/InGaAs/InP DHBT designed here effectively eliminates the energy spike at the B-C junction and improves the device performance.
基金
国家重点基础研究发展规划资助项目(批准号:2002CB311902)~~