AuCl_(3)掺杂对碳纳米管晶体管的电学性能调控及特性分析  

Modulation of electrical properties in carbon nanotube field-effect transistors through AuCl3 doping

作　　者：宋明旭 王怀鹏 孙翊淋 蔡理[1] 杨晓阔[1] 谢丹[2] Song Ming-Xu;Wang Huai-Peng;Sun Yi-Lin;Cai Li;Yang Xiao-Kuo;Xie Dan(Department of Foundation,Air Force Engineering University,Xi’an 710051,China;School of Integrated Circuits,Tsinghua University,Beijing 100084,China;School of Integrated Circuits and Electronics,Beijing Institute of Technology,Beijing 100081,China)

机构地区：[1]空军工程大学基础部,西安710051 [2]清华大学集成电路学院,北京100084 [3]北京理工大学集成电路与电子学院,北京100081

出　　处：《物理学报》2021年第23期380-387,共8页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:52072204);国家重点研发计划(批准号:2016YFA0200200);国家博士后创新人才支持计划(批准号:BX20200049);陕西省自然科学基础研究计划(批准号:2021JM-221,2020JQ-470)资助的课题。

摘　　要：碳纳米管晶体管作为新一代纳米器件,由于缺乏成熟的阈值电压调控机制,仍难以运用到实际逻辑电路中.本文提出了一种简单易实现且能够大规模处理的表面掺杂方法,通过AuCl_(3)的p型掺杂作用来实现对晶体管阈值电压的有效调控,研究了不同掺杂浓度对碳纳米管电学性能的影响.实验结果表明,在低掺杂浓度条件下,不仅实现了晶体管阈值电压稳定调控,器件导电性能也大幅提高,迁移率提升2-3倍.更进一步地,研究了退火对掺杂后器件的电学性能影响,发现在同等掺杂条件下,退火温度达到50℃时,p型掺杂效果最佳.最后采用第一性原理计算方法,验证了金离子对碳纳米管的掺杂调控机制.这项研究为未来实现大面积低功耗逻辑电路以及高性能电子器件提供了重要指导.Carbon nanotube-based field-effect transistors(CNFETs),as a new generation of nanodevices,are still difficult to apply to actual logic circuits due to the lack of a mature threshold voltage control mechanism.Here in this work,a feasible and large-scale processing surface doping method is demonstrated to effectively modulate the threshold voltage of CNFETs through the p-type doping effect of gold chloride(AuCl_(3)).A comprehensive mapping from electrical parameters(I_(on)/I_(off),V_(th) and mobility)to doping concentration is carefully investigated,demonstrating a p-doping effect induced by surface charge transfer between Au^(3+)and carbon nanotube networks(CNTs).Threshold voltage of CNFETs can be effectively adjusted by varying the doping concentration.More importantly,the devices doped with low concentration AuCl_(3) exhibit good electrical properties including greatly improved electrical conductivity,2–3 times higher in mobility than intrinsic carbon nanotubes.Furthermore,the effects of annealing on the electrical properties of the AuCl_(3)-doping CNFETs are studied,demonstrating that the p-type doping effect reaches the optimized state at a temperature of 50℃.Finally,first-principles calculation method is used to verify the doping control mechanism of Au3+to carbon nanotubes.This research provides important guidance for realizing large-area low-power logic circuits and high-performance electronic devices in the future.

关 键 词：碳纳米管网络 表面掺杂 阈值电压调控 密度泛函理论 

分 类 号：TN325[电子电信—物理电子学]