子阱及非对称势垒对GaN RTD电学特性的影响  

Influence of sub-quantum-well and asymmetric quantum-barrier structures on the electrical characteristics of GaN RTD

作　　者：苏娟 谭为[1] 高博[2] SU Juan;TAN Wei;GAO Bo(Institute of Electronic Engineering&Microsystem and Terahertz Research Center,China Academy of Engineering Physics,Chengdu Sichuan610299,China;College of Physical Science and Technology,Sichuan University,Chengdu Sichuan610065,China)

机构地区：[1]中国工程物理研究院微系统与太赫兹研究中心,四川成都610299 [2]四川大学物理科学与技术学院,四川成都610065

出　　处：《太赫兹科学与电子信息学报》2017年第5期855-860,共6页Journal of Terahertz Science and Electronic Information Technology

基　　金：科学挑战专题资助项目(TZ2017003);中国工程物理研究院微系统与太赫兹研究中心专项资助项目(MT2015-11-08);中国工程物理研究院-四川大学协同创新联合基金资助项目(CX2014005)

摘　　要：利用Silvaco软件对Al_(0.2)Ga_(0.8)N/GaN共振隧穿二极管(RTD)进行仿真,重点研究了InGaN子量子阱结构及相应非对称势垒结构设计对其电流特性的影响。对比分析了子量子阱结构中InGaN的In组分和子阱厚度对RTD微分负阻(NDR)特性的影响,得出了提升器件性能的最佳参数范围。为了克服Al_(0.2)Ga_(0.8)N/GaN RTD势垒低对器件电流峰谷比(PVCR)的影响,在子量子阱结构的基础上引入了非对称势垒结构设计,通过改变收集区侧势垒的高度和厚度,将AlGaN/GaN的I_p和PVCR由基本结构的0.42 A和1.25,提高到了0.583 A和5.01,实现了器件性能的优化,并为今后的器件研制提供了设计思路。The influence of InGaN sub-quantum-well and asymmetric quantum-barrier structures on Al0.2Ga0.8N/GaN Resonant Tunneling Diodes(RTD)are studied based on Silvaco simulator.Theoretical investigation reveals that there are appropriate ranges of the In composition and thickness for InGaN subquantum-well which can obviously improve the Negative Differential Resistance(NDR)characteristics of RTD.It is also found that by introducing asymmetric quantum-barrier structures in the sub-quantum-well GaN RTD,the I–U characteristic of Peak-to-Valley Current Ratio(PVCR)can be further improved.Numerical simulation shows that RTD with both InGaN sub-quantum-well and asymmetric quantum-barrier structures exhibits the peak current(Ip)and PVCR of 0.583 A and 5.01 respectively,superior to that of the conventional Al0.2Ga0.8N/GaN RTD without sub-quantum-well having Ip of 0.42 A and PVCR of 1.25.The introducing of improved new quantum structures for the low Al composition AlGaN/GaN RTD has provided one of the solutions to solve the contradiction between the device electrical properties and its actual manufacture for the future terahertz applications.

关 键 词：共振隧穿二极管 ALGAN/GAN异质结 InGaN子阱 非对称势垒 

分 类 号：TN31[电子电信—物理电子学]