A tunnel field-effect transistor(TFET) is proposed by combining various advantages together, such as non-uniform gate-oxide layer, hetero-gate-dielectric(HGD), and dual-material control-gate(DMCG) technology. The effe...A tunnel field-effect transistor(TFET) is proposed by combining various advantages together, such as non-uniform gate-oxide layer, hetero-gate-dielectric(HGD), and dual-material control-gate(DMCG) technology. The effects of the length of non-uniform gate-oxide layer and dual-material control-gate on the on-state, off-state, and ambipolar currents are investigated. In addition, radio-frequency performance is studied in terms of gain bandwidth product, cut-off frequency,transit time, and transconductance frequency product. Moreover, the length of non-uniform gate-oxide layer and dualmaterial control-gate are optimized to improve the on-off current ratio and radio-frequency performances as well as the suppression of ambipolar current. All results demonstrate that the proposed device not only suppresses ambipolar current but also improves radio-frequency performance compared with the conventional DMCG TFET, which makes the proposed device a better application prospect in the advanced integrated circuits.展开更多
Electronic and vibrational intra-molecular thermoelectric-like ?gures of merit(ZT_γ~M) are introduced for single molecule nanoelectronic system, using quantum theory of atoms in molecule. These ?gures of merit are us...Electronic and vibrational intra-molecular thermoelectric-like ?gures of merit(ZT_γ~M) are introduced for single molecule nanoelectronic system, using quantum theory of atoms in molecule. These ?gures of merit are used to describe intra-molecular or local energy dissipation/transition(as in Joule-like, Peltier-like, and Thomson-like effects) in?eld effect molecular devices. The ZT_γ~M?gures of merit are computed for two proposed molecular devices. Analysis of the results shows that ZT_γ~Mdepends almost non-linearly on the electric ?eld(EF) strength. Also, the intra-molecular Joule-like heating plays a dominant role in the local energy dissipation, and intra-molecular Thomson-like heating is generally larger than the intra-molecular Peltier-like heating. Introduction of ZT_γ~Mcan be applied to extend the analysis of thermoelectric heating down to molecular and intra-molecular levels, and thus can be used to predict characteristics and performance of any candidate multi-terminal or multi-pole molecular systems prior to their application in real nanoelectronic circuits.展开更多
Two-dimensional(2D)ferroelectric materials,which possess electrically switchable spontaneous polarization and can be easily integrated with semiconductor technologies,is of utmost importance in the advancement of high...Two-dimensional(2D)ferroelectric materials,which possess electrically switchable spontaneous polarization and can be easily integrated with semiconductor technologies,is of utmost importance in the advancement of high-integration low-power nanoelectronics.Despite the experimental discovery of certain 2D ferroelectric materials such as CuInP2S6 and In2Se3,achieving stable ferroelectricity at room temperature in these materials continues to present a significant challenge.Herein,stable ferroelectric order at room temperature in the 2D limit is demonstrated in van der Waals SnP_(2)S_(6) atom layers,which can be fabricated via mechanical exfoliation of bulk SnP_(2)S_(6) crystals.Switchable polarization is observed in thin SnP_(2)S_(6) of~7 nm.Importantly,a van der Waals ferroelectric field-effect transistor(Fe-FET)with ferroelectric SnP_(2)S_(6) as top-gate insulator and ptype WTe0.6Se1.4 as the channel was designed and fabricated successfully,which exhibits a clear clockwise hysteresis loop in transfer characteristics,demonstrating ferroelectric properties of SnP_(2)S_(6) atomic layers.In addition,a multilayer graphene/SnP_(2)S_(6)/multilayer graphene van der Waals vertical heterostructure phototransistor was also fabricated successfully,exhibiting improved optoelectronic performances with a responsivity(R)of 2.9 A/W and a detectivity(D)of 1.4×10^(12) Jones.Our results show that SnP_(2)S_(6) is a promising 2D ferroelectric material for ferroelectric-integrated low-power 2D devices.展开更多
We demonstrate the direct biosensing of the Ebola VP40 matrix protein, using a memristor mode of a liquid-integrated nanodevice, based on a large array of honeycomb-shaped silicon nanowires. To shed more light on the ...We demonstrate the direct biosensing of the Ebola VP40 matrix protein, using a memristor mode of a liquid-integrated nanodevice, based on a large array of honeycomb-shaped silicon nanowires. To shed more light on the principle of biodetection using memristors, we engineered the opening of the current-minima voltage gap VG by involving the third gap-control electrode （gate voltage, VG） into the system. The primary role of VG is to mimic the presence of the charged species of the desired sign at the active area of the sensor. We further showed the advantages of biodetection with an initially opened controlled gap （Vc~ ~a 0）, which allows the detection of the lowest concentrations of the biomolecules carrying arbitrary positive or negative charges; this feature was not present in previous configurations. We compared the bio-memristor performance, in terms of its detection range and sensitivity, to that of the already-known field-effect transistor （FET） mode by operating the same device. To our knowledge, this is the first demonstration of Ebola matrix protein detection using a nanoscaled electrical sensor.展开更多
Multilevel ferroelectric field-effect transistors(FeFETs)integrated with HfO_(2)-based ferroelectric thin films demonstrate tremendous potential in high-speed massive data storage and neuromorphic computing applicatio...Multilevel ferroelectric field-effect transistors(FeFETs)integrated with HfO_(2)-based ferroelectric thin films demonstrate tremendous potential in high-speed massive data storage and neuromorphic computing applications.However,few works have focused on the stability of the multiple memory states in the HfO_(2)-based FeFETs.Here we firstly report the write/read disturb effects on the multiple memory states in the Hf_(0.5)Zr_(0.5)O_(2)(HZO)-based FeFETs.The multiple memory states in HZO-based FeFETs do not show obvious degradation with the write and read disturb cycles.Moreover,the retention characteristics of the intermediate memory states in HZO-based FeFETs with unsaturated ferroelectric polarizations are better than that of the memory state with saturated ferroelectric polarization.Through the deep analysis of the operation principle of in HZO-based FeFETs,we speculate that the better retention properties of intermediate memory states are determined by the less ferroelectric polarization degradation and the weaker ferroelectric polarization shielding.The experimental and theoretical evidences confirm that the long-term stability of the intermediate memory states in HZO-based FeFETs are as robust as that of the saturated memory state,laying a solid foundation for their practical applications.展开更多
基金Project supported by the University Natural Science Research Key Project of Anhui Province,China(Grant No.KJ2017A502)the Introduced Talent Project of Anhui Science and Technology University,China(Grant No.DQYJ201603)+1 种基金the Excellent Talents Supporting Project of Colleges and Universities,China(Grant No.gxyq2018048)the Innovation and Entrepreneurship Training Program for College Students,China(Grant No.2018S10879052)
文摘A tunnel field-effect transistor(TFET) is proposed by combining various advantages together, such as non-uniform gate-oxide layer, hetero-gate-dielectric(HGD), and dual-material control-gate(DMCG) technology. The effects of the length of non-uniform gate-oxide layer and dual-material control-gate on the on-state, off-state, and ambipolar currents are investigated. In addition, radio-frequency performance is studied in terms of gain bandwidth product, cut-off frequency,transit time, and transconductance frequency product. Moreover, the length of non-uniform gate-oxide layer and dualmaterial control-gate are optimized to improve the on-off current ratio and radio-frequency performances as well as the suppression of ambipolar current. All results demonstrate that the proposed device not only suppresses ambipolar current but also improves radio-frequency performance compared with the conventional DMCG TFET, which makes the proposed device a better application prospect in the advanced integrated circuits.
基金Financial supports from the Research and Technology offices of the University of Qom and the University of Isfahan
文摘Electronic and vibrational intra-molecular thermoelectric-like ?gures of merit(ZT_γ~M) are introduced for single molecule nanoelectronic system, using quantum theory of atoms in molecule. These ?gures of merit are used to describe intra-molecular or local energy dissipation/transition(as in Joule-like, Peltier-like, and Thomson-like effects) in?eld effect molecular devices. The ZT_γ~M?gures of merit are computed for two proposed molecular devices. Analysis of the results shows that ZT_γ~Mdepends almost non-linearly on the electric ?eld(EF) strength. Also, the intra-molecular Joule-like heating plays a dominant role in the local energy dissipation, and intra-molecular Thomson-like heating is generally larger than the intra-molecular Peltier-like heating. Introduction of ZT_γ~Mcan be applied to extend the analysis of thermoelectric heating down to molecular and intra-molecular levels, and thus can be used to predict characteristics and performance of any candidate multi-terminal or multi-pole molecular systems prior to their application in real nanoelectronic circuits.
基金This work was supported by the National Key Research and Development Program of China(Nos.2021YFE0194200 and 2021YFA1200903)the National Natural Science Foundation of China(No.22175203)+2 种基金the Natural Science Foundation of Guangdong Province(Nos.2022B1515020065 and 2020A1515110821)the Guangzhou Science and Technology Project(No.202102020126)This work was also supported by the Plan Fostering Project of State Key Laboratory of Optoelectronic Materials and Technologies,of Sun Yatsen University(No.OEMT-2021-PZ-02).
文摘Two-dimensional(2D)ferroelectric materials,which possess electrically switchable spontaneous polarization and can be easily integrated with semiconductor technologies,is of utmost importance in the advancement of high-integration low-power nanoelectronics.Despite the experimental discovery of certain 2D ferroelectric materials such as CuInP2S6 and In2Se3,achieving stable ferroelectricity at room temperature in these materials continues to present a significant challenge.Herein,stable ferroelectric order at room temperature in the 2D limit is demonstrated in van der Waals SnP_(2)S_(6) atom layers,which can be fabricated via mechanical exfoliation of bulk SnP_(2)S_(6) crystals.Switchable polarization is observed in thin SnP_(2)S_(6) of~7 nm.Importantly,a van der Waals ferroelectric field-effect transistor(Fe-FET)with ferroelectric SnP_(2)S_(6) as top-gate insulator and ptype WTe0.6Se1.4 as the channel was designed and fabricated successfully,which exhibits a clear clockwise hysteresis loop in transfer characteristics,demonstrating ferroelectric properties of SnP_(2)S_(6) atomic layers.In addition,a multilayer graphene/SnP_(2)S_(6)/multilayer graphene van der Waals vertical heterostructure phototransistor was also fabricated successfully,exhibiting improved optoelectronic performances with a responsivity(R)of 2.9 A/W and a detectivity(D)of 1.4×10^(12) Jones.Our results show that SnP_(2)S_(6) is a promising 2D ferroelectric material for ferroelectric-integrated low-power 2D devices.
文摘We demonstrate the direct biosensing of the Ebola VP40 matrix protein, using a memristor mode of a liquid-integrated nanodevice, based on a large array of honeycomb-shaped silicon nanowires. To shed more light on the principle of biodetection using memristors, we engineered the opening of the current-minima voltage gap VG by involving the third gap-control electrode （gate voltage, VG） into the system. The primary role of VG is to mimic the presence of the charged species of the desired sign at the active area of the sensor. We further showed the advantages of biodetection with an initially opened controlled gap （Vc~ ~a 0）, which allows the detection of the lowest concentrations of the biomolecules carrying arbitrary positive or negative charges; this feature was not present in previous configurations. We compared the bio-memristor performance, in terms of its detection range and sensitivity, to that of the already-known field-effect transistor （FET） mode by operating the same device. To our knowledge, this is the first demonstration of Ebola matrix protein detection using a nanoscaled electrical sensor.
基金This work was partly supported by the National Natural Science Foundation of China(Grant Nos.52122205,51902274,52072324,and 11932016)the Science and Technology Innovation Program of Hunan Province(Grant No.2020RC2077)the Natural Science Foundation of Hunan Province(Grant No.2019JJ50617).
文摘Multilevel ferroelectric field-effect transistors(FeFETs)integrated with HfO_(2)-based ferroelectric thin films demonstrate tremendous potential in high-speed massive data storage and neuromorphic computing applications.However,few works have focused on the stability of the multiple memory states in the HfO_(2)-based FeFETs.Here we firstly report the write/read disturb effects on the multiple memory states in the Hf_(0.5)Zr_(0.5)O_(2)(HZO)-based FeFETs.The multiple memory states in HZO-based FeFETs do not show obvious degradation with the write and read disturb cycles.Moreover,the retention characteristics of the intermediate memory states in HZO-based FeFETs with unsaturated ferroelectric polarizations are better than that of the memory state with saturated ferroelectric polarization.Through the deep analysis of the operation principle of in HZO-based FeFETs,we speculate that the better retention properties of intermediate memory states are determined by the less ferroelectric polarization degradation and the weaker ferroelectric polarization shielding.The experimental and theoretical evidences confirm that the long-term stability of the intermediate memory states in HZO-based FeFETs are as robust as that of the saturated memory state,laying a solid foundation for their practical applications.
