Physical investigation of subthreshold swing degradation behavior in negative capacitance FET  

作　　者：Mengxuan YANG Qianqian HUANG Kaifeng WANG Chang SU Liang CHEN Yangyuan WANG Ru HUANG 

机构地区：[1]Key Laboratory of Microelectronic Devices and Circuits(MOE),Institute of Microelectronics,Peking University,Beijing 100871,China [2]Beijing Laboratory of Future IC Technology and Science,Peking University,Beijing 100871,China

出　　处：《Science China(Information Sciences)》2022年第6期237-242,共6页中国科学（信息科学）（英文版）

基　　金：supported by the National Key R&D Program of China(Grant No.2018YFB2202800);National Natural Science Foundation of China(Grant Nos.61851401,61822401,61927901,61421005);111 Project(Grant No.B18001)。

摘　　要：Power consumption has become one of the bottlenecks limiting the future development of integrated circuits.Tunnel FETs(TFETs)and negative capacitance FETs(NCFETs)can break the subthreshold swing limitation(60 mV/dec at room temperature)of conventional metal-oxide-semiconductor field-effect transistor(MOSFET)to reduce the operating voltage and thus power consumption.However,induced by the band-to-band tunneling mechanism,TFETs have a subthreshold swing degradation issue and relatively low ON current.Although NCFETs with ferroelectric/dielectric gate stack can theoretically maintain a high ON current comparable to conventional MOSFET,the physical origin of sub-60 SS is controversial and the mechanism of switching behavior in NCFET is still not clear.In this work,by experimentally investigating the whole negative differential capacitance process and its gate voltage amplification coefficient,an intrinsic issue of SS degradation with increased gate voltage is also found in NCFET for the first time.Based on the physical investigation and simulation results,it is shown that the intrinsic SS degradation in NCFET is resulting from the instant dielectric polarization response.Both the decrease of dielectric thickness and the increase of dielectric constant may lead to the severer SS degradation,which is not favorable for scaled NCFETs.

关 键 词：FERROELECTRIC negative differential capacitance effect polarization low power voltage amplification 

分 类 号：TN386[电子电信—物理电子学]