Emulation of advanced synaptic functions of the human brain with electronic devices contributes an important step toward constructing high‐efficiency neuromorphic systems.Ferroelectric materials are promising candida...Emulation of advanced synaptic functions of the human brain with electronic devices contributes an important step toward constructing high‐efficiency neuromorphic systems.Ferroelectric materials are promising candidates as synaptic weight elements in neural network hardware due to their controllable polarization states.However,the increased depolarization field at the na-noscale and the complex fabrication process of the traditional ferroelectric materials hamper the development of high‐density,low‐power,and highly sensitive synaptic devices.Here,we report the implementation of two‐dimensional(2D)ferroelectricα‐In_(2)Se_(3)as an active channel material to emulate typical synaptic functions.Theα‐In_(2)Se_(3)‐based synaptic device fea-tures multimode operations,enabled by the coupled ferroelectric polarization under various voltage pulses applied at both drain and gate terminals.Moreover,the energy consumption can be reduced to~1 pJ by using high‐κdielectric(Al2O3).The successful control of ferroelectric polarizations inα‐In_(2)Se_(3)and its application in artificial synapses are expected to inspire the implementation of 2D ferroelectric materials for future neuromorphic systems.展开更多
Combining logical function and memory characteristics of transistors is an ideal strategy for enhancing computational efficiency of transistor devices.Here,we rationally design a tri-gate two-dimensional(2D)ferroelect...Combining logical function and memory characteristics of transistors is an ideal strategy for enhancing computational efficiency of transistor devices.Here,we rationally design a tri-gate two-dimensional(2D)ferroelectric van der Waals heterostructures device based on copper indium thiophosphate(CuInP_(2)S_(6))and few layers tungsten disulfide(WS_(2)),and demonstrate its multi-functional applications in multi-valued state of data,non-volatile storage,and logic operation.By co-regulating the input signals across the tri-gate,we show that the device can switch functions flexibly at a low supply voltage of 6 V,giving rise to an ultra-high current switching ratio of 107 and a low subthreshold swing of 53.9 mV/dec.These findings offer perspectives in designing smart 2D devices with excellent functions based on ferroelectric van der Waals heterostructures.展开更多
Ferroelectric memory is a promising candidate for next-generation nonvolatile memory owing to its outstanding performance such as low power consump-tion,fast speed,and high endurance.However,the ferroelectricity of co...Ferroelectric memory is a promising candidate for next-generation nonvolatile memory owing to its outstanding performance such as low power consump-tion,fast speed,and high endurance.However,the ferroelectricity of conven-tional ferroelectric materials will be eliminated by the depolarization field when the size drops to the nanometer scale.As a result,the miniaturization of ferroelectric devices was hindered,which makes ferroelectric memory unable to keep up with the development of integrated-circuit(IC)miniaturization.Recently,a two-dimensional(2D)In2Se3 was reported to maintain stable ferro-electricity at the ultrathin scale,which is expected to break through the bottle-neck of miniaturization.Soon,devices based on 2D In2Se3,including the ferroelectric field-effect transistor,ferroelectric channel transistor,synaptic fer-roelectric semiconductor junction,and ferroelectric memristor were demon-strated.However,a comprehensive understanding of the structures and the ferroelectric-switching mechanism of 2D In2Se3 is still lacking.Here,the atomic structures of different phases,the dynamic mechanism of ferroelectric switching,and the performance/functions of the latest devices of 2D In2Se3 are reviewed.Furthermore,the correlations among the structures,the properties,and the device performance are analyzed.Finally,several crucial problems or challenges and possible research directions are put forward.We hope that this review paper can provide timely knowledge and help for the research commu-nity to develop 2D In2Se3 based ferroelectric memory and computing technol-ogy for practical industrial applications.展开更多
基金Ministry of Education—Singapore,Grant/Award Number:MOE‐2019‐T2‐1‐002National Natural Science Foundation of China,Grant/Award Numbers:21872100,U2032147Agency for Science,Technology and Research,Grant/Award Numbers:A1938c0035,A20G9b0135。
文摘Emulation of advanced synaptic functions of the human brain with electronic devices contributes an important step toward constructing high‐efficiency neuromorphic systems.Ferroelectric materials are promising candidates as synaptic weight elements in neural network hardware due to their controllable polarization states.However,the increased depolarization field at the na-noscale and the complex fabrication process of the traditional ferroelectric materials hamper the development of high‐density,low‐power,and highly sensitive synaptic devices.Here,we report the implementation of two‐dimensional(2D)ferroelectricα‐In_(2)Se_(3)as an active channel material to emulate typical synaptic functions.Theα‐In_(2)Se_(3)‐based synaptic device fea-tures multimode operations,enabled by the coupled ferroelectric polarization under various voltage pulses applied at both drain and gate terminals.Moreover,the energy consumption can be reduced to~1 pJ by using high‐κdielectric(Al2O3).The successful control of ferroelectric polarizations inα‐In_(2)Se_(3)and its application in artificial synapses are expected to inspire the implementation of 2D ferroelectric materials for future neuromorphic systems.
基金supported by the National Natural Science Foundation of China(No.62104073)the China Postdoctoral Science Foundation(No.2021M691088)+1 种基金the Pearl River Talent Recruitment Program(No.2019ZT08X639)Z.C.W.acknowledges the European Research Executive Agency(Project 101079184-FUNLAYERS).
文摘Combining logical function and memory characteristics of transistors is an ideal strategy for enhancing computational efficiency of transistor devices.Here,we rationally design a tri-gate two-dimensional(2D)ferroelectric van der Waals heterostructures device based on copper indium thiophosphate(CuInP_(2)S_(6))and few layers tungsten disulfide(WS_(2)),and demonstrate its multi-functional applications in multi-valued state of data,non-volatile storage,and logic operation.By co-regulating the input signals across the tri-gate,we show that the device can switch functions flexibly at a low supply voltage of 6 V,giving rise to an ultra-high current switching ratio of 107 and a low subthreshold swing of 53.9 mV/dec.These findings offer perspectives in designing smart 2D devices with excellent functions based on ferroelectric van der Waals heterostructures.
基金China Postdoctoral Science Foundation,Grant/Award Number:2019M661200National Natural Science Foundation of China,Grant/Award Numbers:11874171,11904118,61922035Fundamental Research Funds for the Central Universities。
文摘Ferroelectric memory is a promising candidate for next-generation nonvolatile memory owing to its outstanding performance such as low power consump-tion,fast speed,and high endurance.However,the ferroelectricity of conven-tional ferroelectric materials will be eliminated by the depolarization field when the size drops to the nanometer scale.As a result,the miniaturization of ferroelectric devices was hindered,which makes ferroelectric memory unable to keep up with the development of integrated-circuit(IC)miniaturization.Recently,a two-dimensional(2D)In2Se3 was reported to maintain stable ferro-electricity at the ultrathin scale,which is expected to break through the bottle-neck of miniaturization.Soon,devices based on 2D In2Se3,including the ferroelectric field-effect transistor,ferroelectric channel transistor,synaptic fer-roelectric semiconductor junction,and ferroelectric memristor were demon-strated.However,a comprehensive understanding of the structures and the ferroelectric-switching mechanism of 2D In2Se3 is still lacking.Here,the atomic structures of different phases,the dynamic mechanism of ferroelectric switching,and the performance/functions of the latest devices of 2D In2Se3 are reviewed.Furthermore,the correlations among the structures,the properties,and the device performance are analyzed.Finally,several crucial problems or challenges and possible research directions are put forward.We hope that this review paper can provide timely knowledge and help for the research commu-nity to develop 2D In2Se3 based ferroelectric memory and computing technol-ogy for practical industrial applications.