The novel HfO2-based ferroelectric field effect transistor(FeFET)is considered a promising candidate for next-genera-tion nonvolatile memory(NVM).However,a series of reliability issues caused by the fatigue effect hin...The novel HfO2-based ferroelectric field effect transistor(FeFET)is considered a promising candidate for next-genera-tion nonvolatile memory(NVM).However,a series of reliability issues caused by the fatigue effect hinder its further develop-ment.Therefore,a comprehensive understanding of the fatigue mechanisms of the device and optimization strategies is essen-tial for its application.The fundamental mechanism of the fatigue effect is attributed to charge trapping and trap generation based on the current studies,and the underlying causes,occurrence locations and specific impacts are analyzed in this review.In particular,the asymmetric trapping/detrapping of electrons and holes,as well as the relationship between the ferroelectric(FE)polarization and charge trapping,are given particular attention.After categorizing and summarizing the current progress,we propose a series of optimization strategies derived based on the fatigue mechanisms.展开更多
Two-dimensional （2D） materials, such as graphene and MoS2 related transition metal dichalcogenides （TMDC）, have attracted much attention for their potential applications. Ferroelectrics, one of the special and tra...Two-dimensional （2D） materials, such as graphene and MoS2 related transition metal dichalcogenides （TMDC）, have attracted much attention for their potential applications. Ferroelectrics, one of the special and traditional dielectric materials, possess a spontaneous electric polarization that can be reversed by the application of an external electric field. In recent years, a new type of device, combining 2D materials with ferroelectrics, has been fabricated. Many novel devices have been fabricated, such as low power consumption memory devices, highly sensitive photo-transistors, etc. using this technique of hybrid systems incorporating ferroelectrics and 2D materials. This paper reviews two types of devices based on field effect transistor （FET） structures with ferroelectric gate dielectric construction （termed FeFET）. One type of device is for logic applications, such as a graphene and TMDC FeFET for fabricating memory units. Another device is for optoelectric applications, such as high performance phototransistors using a graphene p-n junction. Finally, we discuss the prospects for future applications of 2D material FeFET.展开更多
The single event effect in ferroelectric-gate field-effect transistor （FeFET） under heavy ion irradiation is investigated in this paper. The simulation results show that the transient responses are much lower in a F...The single event effect in ferroelectric-gate field-effect transistor （FeFET） under heavy ion irradiation is investigated in this paper. The simulation results show that the transient responses are much lower in a FeFET than in a conventional metal-oxide-semiconductor field-effect transistor （MOSFET） when the ion strikes the channel. The main reason is that the polarization-induced charges （the polarization direction here is away from the silicon surface） bring a negative surface po- tential which will affect the distribution of carders and charge collection in different electrodes significantly. The simulation results are expected to explain that the FeFET has a relatively good immunity to single event effect.展开更多
We study the charge trapping phenomenon that restricts the endurance of n-type ferroelectric field-effect transistors(FeFETs)with metal/ferroelectric/interlayer/Si(MFIS)gate stack structure.In order to explore the phy...We study the charge trapping phenomenon that restricts the endurance of n-type ferroelectric field-effect transistors(FeFETs)with metal/ferroelectric/interlayer/Si(MFIS)gate stack structure.In order to explore the physical mechanism of the endurance failure caused by the charge trapping effect,we first establish a model to simulate the electron trapping behavior in n-type Si FeFET.The model is based on the quantum mechanical electron tunneling theory.And then,we use the pulsed I_d-V_g method to measure the threshold voltage shift between the rising edges and falling edges of the FeFET.Our model fits the experimental data well.By fitting the model with the experimental data,we get the following conclusions.(i)During the positive operation pulse,electrons in the Si substrate are mainly trapped at the interface between the ferroelectric(FE)layer and interlayer(IL)of the FeFET gate stack by inelastic trap-assisted tunneling.(ii)Based on our model,we can get the number of electrons trapped into the gate stack during the positive operation pulse.(iii)The model can be used to evaluate trap parameters,which will help us to further understand the fatigue mechanism of FeFET.展开更多
Optoelectronic memristive devices that enable neuromorphic sensory computing with integrated sensing,memory and processing functionalities,have been identified as a promising element for next-generation artificial vis...Optoelectronic memristive devices that enable neuromorphic sensory computing with integrated sensing,memory and processing functionalities,have been identified as a promising element for next-generation artificial vision systems.However,the optoelectronic memristive dynamics of these devices are largely based on engineered structures and/or innovative functional nanomaterials,presenting critical challenges for their silicon complementary metal-oxide-semiconductor(CMOS)technology compatibility at a scalable application perspective.Here we demonstrate a CMOS-compatible optoelectronic memristive device based on the aluminium scandium nitride(AlScN)ferroelectric/two-dimensional(2D)semiconductor heterostructure enabled ferroelectric field-effect transistor(FeFET).We show that such FeFETs can be fabricated under the back-end-of-line(BEOL)thermal budget and exhibit non-volatile electronic memory properties.Harnessing the light-induced ferroelectric domain reconfiguration in the AlScN layer,these devices offer light-tunable short-and long-term memristive properties,directly linking light stimulation history to electronic dynamics.Such a working principle enables rich optoelectronic synaptic functions and the implementation of the psychological human visual memory model,offering a critical demonstration for optical neuromorphic sensory computing.Furthermore,a linear and non-volatile dependence of the photoresponse current on the light intensity is exploited for the optical information decoding.Our results mark new opportunities for CMOS-compatible optoelectronic memristive devices as the hardware basis of next-generation neuromorphic vision architectures.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supported in part by the National Natural Science Foundation of China(NSFC)under Grant 62304246,62404246,62425407the Ministry of Science and Technology(MOST)of China under Grant 2022YFB3608400+1 种基金the Young Elite Scientists Sponsorship Program by the China Association for Science and Technology(CAST)under Grant 2022QNRC001the Youth Innovation Promotion Association of Chinese Academy of Sciences under Grant 2020120,2023127.
文摘The novel HfO2-based ferroelectric field effect transistor(FeFET)is considered a promising candidate for next-genera-tion nonvolatile memory(NVM).However,a series of reliability issues caused by the fatigue effect hinder its further develop-ment.Therefore,a comprehensive understanding of the fatigue mechanisms of the device and optimization strategies is essen-tial for its application.The fundamental mechanism of the fatigue effect is attributed to charge trapping and trap generation based on the current studies,and the underlying causes,occurrence locations and specific impacts are analyzed in this review.In particular,the asymmetric trapping/detrapping of electrons and holes,as well as the relationship between the ferroelectric(FE)polarization and charge trapping,are given particular attention.After categorizing and summarizing the current progress,we propose a series of optimization strategies derived based on the fatigue mechanisms.
基金Project supported by the Major State Basic Research Development Program of China(Grant Nos.2013CB922302 and 2016YFA0203900)the Natural Science Foundation of China(Grant Nos.11322441,614404147,61574152,and 61674157)the Key Research Project of Frontier Science of Chinese Academy of Sciences(Grant Nos.QYZDB-SSW-JSC016 and QYZDB-SSW-JSC031)
文摘Two-dimensional （2D） materials, such as graphene and MoS2 related transition metal dichalcogenides （TMDC）, have attracted much attention for their potential applications. Ferroelectrics, one of the special and traditional dielectric materials, possess a spontaneous electric polarization that can be reversed by the application of an external electric field. In recent years, a new type of device, combining 2D materials with ferroelectrics, has been fabricated. Many novel devices have been fabricated, such as low power consumption memory devices, highly sensitive photo-transistors, etc. using this technique of hybrid systems incorporating ferroelectrics and 2D materials. This paper reviews two types of devices based on field effect transistor （FET） structures with ferroelectric gate dielectric construction （termed FeFET）. One type of device is for logic applications, such as a graphene and TMDC FeFET for fabricating memory units. Another device is for optoelectric applications, such as high performance phototransistors using a graphene p-n junction. Finally, we discuss the prospects for future applications of 2D material FeFET.
基金Project supported by the Key Project of the National Natural Science Foundation of China(Grant No.11032010)the National Natural Science Foundationof China(Grant Nos.51072171,61274107,61176093,and 11275163)+6 种基金the Program for Changjiang Scholars and Innovative Research Team in University,China(Grant No.IRT1080)the 973 Program,China(Grant No.2012CB326404)the Key Project of Natural Science Foundation of Hunan Province,China(Grant No.13JJ2023)the Key Project of Scientific Research Fund of Education Department of Hunan Province,China(Grant No.12A129)the Innovation Foundation of Hunan Province of China for Postgraduate,China(Grant No.CX2013B261)the Doctoral Program of Higher Education of China(GrantNo.20104301110001)the Aid Program for Science and Technology Innovative Research Team in Higher Educational Institutions of Hunan Province,China
文摘The single event effect in ferroelectric-gate field-effect transistor （FeFET） under heavy ion irradiation is investigated in this paper. The simulation results show that the transient responses are much lower in a FeFET than in a conventional metal-oxide-semiconductor field-effect transistor （MOSFET） when the ion strikes the channel. The main reason is that the polarization-induced charges （the polarization direction here is away from the silicon surface） bring a negative surface po- tential which will affect the distribution of carders and charge collection in different electrodes significantly. The simulation results are expected to explain that the FeFET has a relatively good immunity to single event effect.
基金Project supported by the National Natural Science Foundation of China(Grant No.92264104)。
文摘We study the charge trapping phenomenon that restricts the endurance of n-type ferroelectric field-effect transistors(FeFETs)with metal/ferroelectric/interlayer/Si(MFIS)gate stack structure.In order to explore the physical mechanism of the endurance failure caused by the charge trapping effect,we first establish a model to simulate the electron trapping behavior in n-type Si FeFET.The model is based on the quantum mechanical electron tunneling theory.And then,we use the pulsed I_d-V_g method to measure the threshold voltage shift between the rising edges and falling edges of the FeFET.Our model fits the experimental data well.By fitting the model with the experimental data,we get the following conclusions.(i)During the positive operation pulse,electrons in the Si substrate are mainly trapped at the interface between the ferroelectric(FE)layer and interlayer(IL)of the FeFET gate stack by inelastic trap-assisted tunneling.(ii)Based on our model,we can get the number of electrons trapped into the gate stack during the positive operation pulse.(iii)The model can be used to evaluate trap parameters,which will help us to further understand the fatigue mechanism of FeFET.
基金supported by the National Key R&D Program of China(2023YFB4402303)the National Natural Science Foundation of China(62274128,92264202,62404174,62090033,and 62025402)+2 种基金the Zhejiang Provincial Natural Science Foundation of China(LDT23F0402,LDT23F04023F04,and LDT23F04024F04)the Key Research and Development Program of Ningbo City(2023Z071)the Postdoctoral Fellowship Program of CPSF(GZC20250382).
文摘Optoelectronic memristive devices that enable neuromorphic sensory computing with integrated sensing,memory and processing functionalities,have been identified as a promising element for next-generation artificial vision systems.However,the optoelectronic memristive dynamics of these devices are largely based on engineered structures and/or innovative functional nanomaterials,presenting critical challenges for their silicon complementary metal-oxide-semiconductor(CMOS)technology compatibility at a scalable application perspective.Here we demonstrate a CMOS-compatible optoelectronic memristive device based on the aluminium scandium nitride(AlScN)ferroelectric/two-dimensional(2D)semiconductor heterostructure enabled ferroelectric field-effect transistor(FeFET).We show that such FeFETs can be fabricated under the back-end-of-line(BEOL)thermal budget and exhibit non-volatile electronic memory properties.Harnessing the light-induced ferroelectric domain reconfiguration in the AlScN layer,these devices offer light-tunable short-and long-term memristive properties,directly linking light stimulation history to electronic dynamics.Such a working principle enables rich optoelectronic synaptic functions and the implementation of the psychological human visual memory model,offering a critical demonstration for optical neuromorphic sensory computing.Furthermore,a linear and non-volatile dependence of the photoresponse current on the light intensity is exploited for the optical information decoding.Our results mark new opportunities for CMOS-compatible optoelectronic memristive devices as the hardware basis of next-generation neuromorphic vision architectures.
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.
