Design optimization of a silicon-germanium heterojunction negative capacitance gate-all-around tunneling field effect transistor based on a simulation study  

作　　者：魏伟杰 吕伟锋 韩颖 张彩云 谌登科 Weijie Wei;Weifeng Lü;Ying Han;Caiyun Zhang;Dengke Chen(School of Microelectronics,Hangzhou Dianzi University,Hangzhou 310018,China)

机构地区：[1]School of Microelectronics,Hangzhou Dianzi University,Hangzhou 310018,China

出　　处：《Chinese Physics B》2023年第9期436-442,共7页中国物理B（英文版）

基　　金：supported by the Zhejiang Provincial Natural Science Foundation of China(Grant No.LY22F040001);the National Natural Science Foundation of China(Grant No.62071160);the Graduate Scientific Research Foundation of Hangzhou Dianzi University。

摘　　要：The steep sub-threshold swing of a tunneling field-effect transistor(TFET)makes it one of the best candidates for lowpower nanometer devices.However,the low driving capability of TFETs prevents their application in integrated circuits.In this study,an innovative gate-all-around(GAA)TFET,which represents a negative capacitance GAA gate-to-source overlap TFET(NCGAA-SOL-TFET),is proposed to increase the driving current.The proposed NCGAA-SOL-TFET is developed based on technology computer-aided design(TCAD)simulations.The proposed structure can solve the problem of the insufficient driving capability of conventional TFETs and is suitable for sub-3-nm nodes.In addition,due to the negative capacitance effect,the surface potential of the channel can be amplified,thus enhancing the driving current.The gateto-source overlap(SOL)technique is used for the first time in an NCGAA-TFET to increase the band-to-band tunneling rate and tunneling area at the silicon-germanium heterojunction.By optimizing the design of the proposed structure via adjusting the SOL length and the ferroelectric layer thickness,a sufficiently large on-state current of 17.20μA can be achieved and the threshold voltage can be reduced to 0.31 V with a sub-threshold swing of 44.98 mV/decade.Finally,the proposed NCGAA-SOL-TFET can overcome the Boltzmann limit-related problem,achieving a driving current that is comparable to that of the traditional complementary metal-oxide semiconductor devices.

关 键 词：negative capacitance(NC) gate-all-around(GAA) silicon-germanium heterojunction gate-tosource overlap(SOL) 

分 类 号：TN386[电子电信—物理电子学]