The electrical characteristics of a double-gate armchair silicene nanoribbon field-effect-transistor （DG ASiNR FET） are thoroughly investigated by using a ballistic quantum transport model based on non-equilibrium G...The electrical characteristics of a double-gate armchair silicene nanoribbon field-effect-transistor （DG ASiNR FET） are thoroughly investigated by using a ballistic quantum transport model based on non-equilibrium Green＇s function （NEGF） approach self-consistently coupled with a three-dimensional （3D） Poisson equation. We evaluate the influence of variation in uniaxial tensile strain, ribbon temperature and oxide thickness on the on-off current ratio, subthreshold swing, transconductance and the delay time of a 12-nm-length ultranarrow ASiNR FET. A novel two-parameter strain mag- nitude and temperature-dependent model is presented for designing an optimized device possessing balanced amelioration of all the electrical parameters. We demonstrate that employing HfO2 as the gate insulator can be a favorable choice and simultaneous use of it with proper combination of temperature and strain magnitude can achieve better device performance. Furthermore, a general model power （GMP） is derived which explicitly provides the electron effective mass as a function of the bandgap of a hydrogen passivated ASiNR under strain.展开更多
The interface between oxide/oxide layers shows an inhomogeneous charge transport behavior,which reveals a high conductivity owing to interface-doped.One typical example is the hetero-interface between ZnO film and oth...The interface between oxide/oxide layers shows an inhomogeneous charge transport behavior,which reveals a high conductivity owing to interface-doped.One typical example is the hetero-interface between ZnO film and other wide band gap oxides(e.g.,Al_(2)O_(3),TiO_(2),and HfO_(2)).It is thus quite evident that the ZnO/other oxides hetero-interface contains high density electron carriers effectively screening the gate-induced electric field.Thus,an extremely weak gate modulation in ZnO film was showed,resulting in very low on/off ratio of 1.69 in top-gate field-effect-transistor(TG-FET)configuration.So,to extend the usage of ZnO TG-FET is not quite possible toward further practical application.Herein,we clarified the correlation of inhomogeneous region in oxide/oxide hetero-junction by systematically study.Our work suggests that a self-assembly of molecules(SAM)buffer layer is suitable for tuning the inhomogeneous charge transport in ZnO film,which not only reduces the interface trap density,but also effectively enhances the gate electric field modulation at the hetero-interface.We further report the robust fabrication of TG-FET arrays based on ZnO thin film,using an ultra-thin alkylphosphonic acid molecule monolayer as buffer layer.Our device demonstrates a pronounced ultrahigh on/off ratio of≥10^(8),which is 8-order of magnitude higher than that of a device without buffer layer.For the highly reliable arrays,our device exhibits a high yield of over 93%with an average on/off ratio of^10^(7) across the entire wafer scale,mobility(18.5 cm^(2)/(V·s)),an extended bias-stressing(~2,000 s)and long-stability(~150 days)under ambient conditions.展开更多
针对GFET器件中杂质和缺陷引起的本征通道不均匀而导致传统噪声模型拟合度较差的问题,提出了一种基于电荷的石墨烯场效应晶体管(Graphene Field Effect Transistors,GFET)等效噪声电路模型。首先考虑了GFET器件非互易性的影响,通过在小...针对GFET器件中杂质和缺陷引起的本征通道不均匀而导致传统噪声模型拟合度较差的问题,提出了一种基于电荷的石墨烯场效应晶体管(Graphene Field Effect Transistors,GFET)等效噪声电路模型。首先考虑了GFET器件非互易性的影响,通过在小信号等效电路中引入电荷受控源来模拟器件在相关偏置条件下本征通道电荷传输特性,并从S参数中提取小信号模型参数,建立基于电荷的小信号等效电路模型。然后对GFET的高频噪声特性分析,采用PRC模型方法进行表征,噪声去嵌技术获取噪声模型参数,进一步建立基于电荷的GFET等效噪声电路模型。最后,在1~50GHz的频率范围内评估其射频性能,得到S参数最大误差仅为2.2%,最小噪声系数平均误差为1.2%,并将截止频率、噪声参数等射频指标与实验数据比较,验证了所提出模型的有效性和实用性。展开更多
文摘The electrical characteristics of a double-gate armchair silicene nanoribbon field-effect-transistor （DG ASiNR FET） are thoroughly investigated by using a ballistic quantum transport model based on non-equilibrium Green＇s function （NEGF） approach self-consistently coupled with a three-dimensional （3D） Poisson equation. We evaluate the influence of variation in uniaxial tensile strain, ribbon temperature and oxide thickness on the on-off current ratio, subthreshold swing, transconductance and the delay time of a 12-nm-length ultranarrow ASiNR FET. A novel two-parameter strain mag- nitude and temperature-dependent model is presented for designing an optimized device possessing balanced amelioration of all the electrical parameters. We demonstrate that employing HfO2 as the gate insulator can be a favorable choice and simultaneous use of it with proper combination of temperature and strain magnitude can achieve better device performance. Furthermore, a general model power （GMP） is derived which explicitly provides the electron effective mass as a function of the bandgap of a hydrogen passivated ASiNR under strain.
基金supported by the National Research Foundation of Korea(NRF)grant funded by the Korea government(MSIT)(No.NRF-2018R1A2B2008069)Multi-Ministry Collaborative R&D Program through the National Research Foundation of Korea,funded by KNPA,MSIT,MOTIE,ME,and NFA(No.2017M3D9A1073539)+1 种基金supported by the Bio&Medical Technology Development Program of the National Research Foundation(NRF)funded by the Ministry of Science&ICT(No.NRF-2020M3A9E4039241)support from the Institute for Basic Science(No.IBS-R011-D1).
文摘The interface between oxide/oxide layers shows an inhomogeneous charge transport behavior,which reveals a high conductivity owing to interface-doped.One typical example is the hetero-interface between ZnO film and other wide band gap oxides(e.g.,Al_(2)O_(3),TiO_(2),and HfO_(2)).It is thus quite evident that the ZnO/other oxides hetero-interface contains high density electron carriers effectively screening the gate-induced electric field.Thus,an extremely weak gate modulation in ZnO film was showed,resulting in very low on/off ratio of 1.69 in top-gate field-effect-transistor(TG-FET)configuration.So,to extend the usage of ZnO TG-FET is not quite possible toward further practical application.Herein,we clarified the correlation of inhomogeneous region in oxide/oxide hetero-junction by systematically study.Our work suggests that a self-assembly of molecules(SAM)buffer layer is suitable for tuning the inhomogeneous charge transport in ZnO film,which not only reduces the interface trap density,but also effectively enhances the gate electric field modulation at the hetero-interface.We further report the robust fabrication of TG-FET arrays based on ZnO thin film,using an ultra-thin alkylphosphonic acid molecule monolayer as buffer layer.Our device demonstrates a pronounced ultrahigh on/off ratio of≥10^(8),which is 8-order of magnitude higher than that of a device without buffer layer.For the highly reliable arrays,our device exhibits a high yield of over 93%with an average on/off ratio of^10^(7) across the entire wafer scale,mobility(18.5 cm^(2)/(V·s)),an extended bias-stressing(~2,000 s)and long-stability(~150 days)under ambient conditions.
文摘针对GFET器件中杂质和缺陷引起的本征通道不均匀而导致传统噪声模型拟合度较差的问题,提出了一种基于电荷的石墨烯场效应晶体管(Graphene Field Effect Transistors,GFET)等效噪声电路模型。首先考虑了GFET器件非互易性的影响,通过在小信号等效电路中引入电荷受控源来模拟器件在相关偏置条件下本征通道电荷传输特性,并从S参数中提取小信号模型参数,建立基于电荷的小信号等效电路模型。然后对GFET的高频噪声特性分析,采用PRC模型方法进行表征,噪声去嵌技术获取噪声模型参数,进一步建立基于电荷的GFET等效噪声电路模型。最后,在1~50GHz的频率范围内评估其射频性能,得到S参数最大误差仅为2.2%,最小噪声系数平均误差为1.2%,并将截止频率、噪声参数等射频指标与实验数据比较,验证了所提出模型的有效性和实用性。
