This paper investigates the variation of electrical characteristic of indium gallium zinc oxide (IGZO) thin film transistors (TFTs) under gate bias stress. The devices are subjected to positive and negative gate bias ...This paper investigates the variation of electrical characteristic of indium gallium zinc oxide (IGZO) thin film transistors (TFTs) under gate bias stress. The devices are subjected to positive and negative gate bias stress for prolonged time periods. The effect of bias stress time and polarity on the transistor current equation is investigated and the underlying effects responsible for these variations are determined. Negative gate stress produces a positive shift in the threshold voltage. This can be noted as a variation from prior studies. Due to variation of power factor (n) from two, the integral method is implemented to extract threshold voltage (vt) and power factor (n). Effective, mobility (ueff), drain to source resistance (RDS) and constant k' is also extracted from the device characteristics. The unstressed value of n is deter-mined to be 2.5. The power factor increases with gate bias stress time. The distribution of states in the conduction band is revealed by the variation in power factor.展开更多
Glucose,ascorbic acid(AA),uric acid(UA),and dopamine(DA)are vital biomarkers whose dynamic concentrations correlate with critical diseases;however,multiplexed detection remains challenging for conventional electrochem...Glucose,ascorbic acid(AA),uric acid(UA),and dopamine(DA)are vital biomarkers whose dynamic concentrations correlate with critical diseases;however,multiplexed detection remains challenging for conventional electrochemical sensors because of their limited sensitivity and selectivity.Here,we present a millimeter-scale all-poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate)(PEDOT:PSS)organic electrochemical transistor(OECT)platform that integrates dual-mode sensing with enzyme/metal-free operation for ultrasensitive biomarker monitoring.By engineering polycrystalline PEDOT:PSS channels via H_2 SO_4 post-treatment,the device achieves record-high conductivity(about(2312.0±29.9)S·cm^(–1)),maximum transconductance(about(2.82±0.12)mS),and on/off ratio(about 210.0±7.8),enabling signal amplification at low gate voltages.The dual-mode strategy combines the selectivity of electrochemistry with the sensitivity of OECTs,realizing simultaneous detection of glucose,AA,UA,and DA with clinical-level sensitivity:detection limits down to 8 nmol·L^(–1)(glucose),0.5 nmol·L^(–1)(AA),5 nmol·L^(–1)(DA),and 0.5 nmol·L^(–1)(UA).Validation using human urine samples yielded recovery rates of 94%–114%.This flexible sensing platform provides a new pathway for the development of wearable biosensors for precision diagnostics.展开更多
Field-effect nanofluidic transistors(FENTs),biomimicking the structure and functionality of neuron,act as biological transistors with the ability to gate switching responses to external stimuli.The switching ratio has...Field-effect nanofluidic transistors(FENTs),biomimicking the structure and functionality of neuron,act as biological transistors with the ability to gate switching responses to external stimuli.The switching ratio has been verified to evaluate the performance of FENTs,but until recently,the response time,another crucial indicator,has been ignored.Employing finite-element method,we investigated the relationship among gate charge,switching ratio and response time by divisionally manipulating gate charge,including entrance surface and the surface of confinement space,for ion transport to optimize switching capability.The dual-split gate charge on FENTs exhibits synergistic effect on switching response.Based on the two regional gate charge on FENTs,multivalence ions in lower concentration,high aspect ratio and single channel show higher switching ratio but longer response time compared to monovalent ions.The findings highlight the necessity of balancing these two signals in FENTs and offer insights for optimizing their design and expanding applications to dual-signal-detection iontronics.展开更多
The performance damage mechanism of InP-based high electron mobility transistors(HEMTs) after proton irradiation has been investigated comprehensively through induced defects.The effects of the defect type, defect ene...The performance damage mechanism of InP-based high electron mobility transistors(HEMTs) after proton irradiation has been investigated comprehensively through induced defects.The effects of the defect type, defect energy level with respect to conduction band ET, and defect concentration on the transfer and output characteristics of the device are discussed based on hydrodynamic model and Shockley–Read–Hall recombination model.The results indicate that only acceptorlike defects have a significant influence on device operation.Meanwhile, as defect energy level ETshifts away from conduction band, the drain current decreases gradually and finally reaches a saturation value with ETabove 0.5 eV.This can be attributed to the fact that at sufficient deep level, acceptor-type defects could not be ionized any more.Additionally,the drain current and transconductance degrade more severely with larger acceptor concentration.These changes of the electrical characteristics with proton radiation could be accounted for by the electron density reduction in the channel region from induced acceptor-like defects.展开更多
Self-heating effect in amorphous InGaZnO thin-film transistors remains a critical issue that degrades device performance and stability, hindering their wider applications. In this work, pulsed current–voltage analysi...Self-heating effect in amorphous InGaZnO thin-film transistors remains a critical issue that degrades device performance and stability, hindering their wider applications. In this work, pulsed current–voltage analysis has been applied to explore the physics origin of self-heating induced degradation, where Joule heat is shortly accumulated by drain current and dissipated in repeated time cycles as a function of gate bias. Enhanced positive threshold voltage shift is observed at reduced heat dissipation time, higher drain current, and increased gate width. A physical picture of Joule heating assisted charge trapping process has been proposed and then verified with pulsed negative gate bias stressing scheme, which could evidently counteract the self-heating effect through the electric-field assisted detrapping process. As a result, this pulsed gate bias scheme with negative quiescent voltage could be used as a possible way to actively suppress self-heating related device degradation.展开更多
In this work,we demonstrated the InSnO(ITO)TFTs passivated with SiO_(2)via the PECVD process compatible with large-area production for the first time.The passivated ITO TFTs with various channel thicknesses(t_(ch)=4,5...In this work,we demonstrated the InSnO(ITO)TFTs passivated with SiO_(2)via the PECVD process compatible with large-area production for the first time.The passivated ITO TFTs with various channel thicknesses(t_(ch)=4,5,6 nm)exhibit excellent electrical performance and superior uniformity.The reliability properties of ITO TFTs were evaluated in detail under positive bias stress(PBS)conditions before and after passivation.Compared to the devices without passivation,the passivated devices have only 50%threshold voltage degradation(ΔV_(th))and 50%newly generated traps due to excellent isolation of the ambient atmosphere.The negligible performance degradation of ITO TFTs with passivation during negative bias stress(NBS)and negative bias temperature stress(NBTS)verifies the outstanding immunity to the water vapor of the SiO_(2)passivation layer.Overall,the ITO TFT with the t_(ch)of 6 nm and with SiO_(2)passivation exhibits the best performance in terms of electrical properties,uniformity,and reliability,which is promising in large-area production.展开更多
Displacement damage induced by neutron irradiation in China Spallation Neutron Source(CSNS) is studied on bipolar transistors with lateral PNP, substrate PNP, and vertical NPN configurations, respectively. Comparison ...Displacement damage induced by neutron irradiation in China Spallation Neutron Source(CSNS) is studied on bipolar transistors with lateral PNP, substrate PNP, and vertical NPN configurations, respectively. Comparison of the effects on different type transistors is conducted based on displacement damage factor, and the differences are analyzed through minority carrier lifetime calculation and structure analysis. The influence of CSNS neutrons irradiation on the lateral PNP transistors is analyzed by the gate-controlled method, including the oxide charge accumulation, surface recombine velocity,and minority carrier lifetime. The results indicate that the total ionizing dose in CSNS neutron radiation environment is negligible in this study. The displacement damage factors based on 1-MeV equivalent neutron flux of different transistors are consistent between Xi’an pulse reactor(XAPR) and CSNS.展开更多
Nitrogen doping is a promising way to modulate the electrical properties of graphene to realize graphene-based electronics and promise fascinating properties and applications.Herein,we report a method to noncovalently...Nitrogen doping is a promising way to modulate the electrical properties of graphene to realize graphene-based electronics and promise fascinating properties and applications.Herein,we report a method to noncovalently assembly titanium(Ⅳ) bis(ammoniumlactato) dihydroxide(Ti complex) on nitrogen-doped graphene to create a reliable hybrids which can be used as a reversible chemical induced switching.As the adsorption and desorption of Ti complex in sequential treatments,the conductance of the nitrogen-doped graphene transistors was finely modulated.Control experiments with pristine graphene clearly demonstrated the important effort of the nitrogen in this chemical sensor.Under optimized conditions,nitrogen-doped graphene transistors open up new ways to develop multifunctional devices with high sensitivity.展开更多
We demonstrate transitions of hopping behaviors for delocalized electrons through the discrete dopant-induced quantum dots in n-doped silicon junctionless nanowire transistors by the temperature-dependent conductance ...We demonstrate transitions of hopping behaviors for delocalized electrons through the discrete dopant-induced quantum dots in n-doped silicon junctionless nanowire transistors by the temperature-dependent conductance characteristics.There are two obvious transition platforms within the critical temperature regimes for the experimental conductance data,which are extracted from the unified transfer characteristics for different temperatures at the gate voltage positions of the initial transconductance gm peak in Vg1 and valley in Vg2. The crossover temperatures of the electron hopping behaviors are analytically determined by the temperature-dependent conductance at the gate voltages Vg1 and Vg2. This finding provides essential evidence for the hopping electron behaviors under the influence of thermal activation and long-range Coulomb interaction.展开更多
Besides the common short-channel effect(SCE)of threshold voltage(V_(th))roll-off during the channel length(L)downscaling of In GaZnO(IGZO)thin-film transistors(TFTs),an opposite V_(th)roll-up was reported in this work...Besides the common short-channel effect(SCE)of threshold voltage(V_(th))roll-off during the channel length(L)downscaling of In GaZnO(IGZO)thin-film transistors(TFTs),an opposite V_(th)roll-up was reported in this work.Both roll-off and roll-up effects of Vth were comparatively investigated on IGZO transistors with varied gate insulator(GI),source/drain(S/D),and device architecture.For IGZO transistors with thinner GI,the SCE was attenuated due to the enhanced gate controllability over the variation of channel carrier concentration,while the Vth roll-up became more noteworthy.The latter was found to depend on the relative ratio of S/D series resistance(R_(SD))over channel resistance(R_(CH)),as verified on transistors with different S/D.Thus,an ideal S/D engineering with small R_(SD)but weak dopant diffusion is highly expected during the downscaling of L and GI in IGZO transistors.展开更多
A sensor,serving as a transducer,produces a quantifiable output in response to a predetermined input stimulus,which may be of a chemical or physical nature.The field of gas detection has experienced a substantial surg...A sensor,serving as a transducer,produces a quantifiable output in response to a predetermined input stimulus,which may be of a chemical or physical nature.The field of gas detection has experienced a substantial surge in research activity,attributable to the diverse functionalities and enhanced accessibility of advanced active materials.In this work,recent advances in gas sensors,specifically those utilizing Field Effect Transistors(FETs),are summarized,including device configurations,response characteristics,sensor materials,and application domains.In pursuing high-performance artificial olfactory systems,the evolution of FET gas sensors necessitates their synchronization with material advancements.These materials should have large surface areas to enhance gas adsorption,efficient conversion of gas input to detectable signals,and strong mechanical qualities.The exploration of gas-sensitive materials has covered diverse categories,such as organic semiconductor polymers,conductive organic compounds and polymers,metal oxides,metal-organic frameworks,and low-dimensional materials.The application of gas sensing technology holds significant promise in domains such as industrial safety,environmental monitoring,and medical diagnostics.This comprehensive review thoroughly examines recent progress,identifies prevailing technical challenges,and outlines prospects for gas detection technology utilizing field effect transistors.The primary aim is to provide a valuable reference for driving the development of the next generation of gas-sensitive monitoring and detection systems characterized by improved sensitivity,selectivity,and intelligence.展开更多
Flexible electronics are transforming our lives by making daily activities more convenient.Central to this innovation are field-effect transistors(FETs),valued for their efficient signal processing,nanoscale fabricati...Flexible electronics are transforming our lives by making daily activities more convenient.Central to this innovation are field-effect transistors(FETs),valued for their efficient signal processing,nanoscale fabrication,low-power consumption,fast response times,and versatility.Graphene,known for its exceptional mechanical properties,high electron mobility,and biocompatibility,is an ideal material for FET channels and sensors.The combination of graphene and FETs has given rise to flexible graphene field-effect transistors(FGFETs),driving significant advances in flexible electronics and sparked a strong interest in flexible biomedical sensors.Here,we first provide a brief overview of the basic structure,operating mechanism,and evaluation parameters of FGFETs,and delve into their material selection and patterning techniques.The ability of FGFETs to sense strains and biomolecular charges opens up diverse application possibilities.We specifically analyze the latest strategies for integrating FGFETs into wearable and implantable flexible biomedical sensors,focusing on the key aspects of constructing high-quality flexible biomedical sensors.Finally,we discuss the current challenges and prospects of FGFETs and their applications in biomedical sensors.This review will provide valuable insights and inspiration for ongoing research to improve the quality of FGFETs and broaden their application prospects in flexible biomedical sensing.展开更多
The instability of p-channel low-temperature polycrystalline silicon thin film transistors(poly-Si TFTs)is investigated under negative gate bias stress(NBS)in this work.Firstly,a series of negative bias stress experim...The instability of p-channel low-temperature polycrystalline silicon thin film transistors(poly-Si TFTs)is investigated under negative gate bias stress(NBS)in this work.Firstly,a series of negative bias stress experiments is performed,the significant degradation behaviors in current-voltage characteristics are observed.As the stress voltage decreases from-25 V to-37 V,the threshold voltage and the sub-threshold swing each show a continuous shift,which is induced by gate oxide trapped charges or interface state.Furthermore,low frequency noise(LFN)values in poly-Si TFTs are measured before and after negative bias stress.The flat-band voltage spectral density is extracted,and the trap concentration located near the Si/SiO2 interface is also calculated.Finally,the degradation mechanism is discussed based on the current-voltage and LFN results in poly-Si TFTs under NBS,finding out that Si-OH bonds may be broken and form Si*and negative charge OH-under negative bias stress,which is demonstrated by the proposed negative charge generation model.展开更多
We have successfully prepared GaN based high electron mobility transistors(HEMTs)on metallic substrates transferred from silicon substrates by electroplating technique.GaN HEMTs on Cu substrates are demonstrated to ba...We have successfully prepared GaN based high electron mobility transistors(HEMTs)on metallic substrates transferred from silicon substrates by electroplating technique.GaN HEMTs on Cu substrates are demonstrated to basically have the same good electric characteristics as the chips on Si substrates.Furthermore,the better heat dissipation of HEMTs on Cu substrates compared to HEMTs on Si substrates is clearly observed by thermoreflectance imaging,showing the promising potential for very high-power and high-temperature operation.This work shows the outstanding ability of HEMT chips on Cu substrates for solving the self-heating effect with the advantages of process simplicity,high yield,and low production requirement.展开更多
Rapid development of artificial intelligence requires the implementation of hardware systems with bioinspired parallel information processing and presentation and energy efficiency.Electrolyte-gated organic transistor...Rapid development of artificial intelligence requires the implementation of hardware systems with bioinspired parallel information processing and presentation and energy efficiency.Electrolyte-gated organic transistors(EGOTs)offer significant advantages as neuromorphic devices due to their ultra-low operation voltages,minimal hardwired connectivity,and similar operation environment as electrophysiology.Meanwhile,ionic–electronic coupling and the relatively low elastic moduli of organic channel materials make EGOTs suitable for interfacing with biology.This review presents an overview of the device architectures based on organic electrochemical transistors and organic field-effect transistors.Furthermore,we review the requirements of low energy consumption and tunable synaptic plasticity of EGOTs in emulating biological synapses and how they are affected by the organic materials,electrolyte,architecture,and operation mechanism.In addition,we summarize the basic operation principle of biological sensory systems and the recent progress of EGOTs as a building block in artificial systems.Finally,the current challenges and future development of the organic neuromorphic devices are discussed.展开更多
The enhancement of mobility has always been a research focus in the field of thin-film transistors(TFTs).In this paper,we report a method using ultra-thin HfO2to improve the electrical performance of indium gallium zi...The enhancement of mobility has always been a research focus in the field of thin-film transistors(TFTs).In this paper,we report a method using ultra-thin HfO2to improve the electrical performance of indium gallium zinc oxide(IGZO)TFTs.HfO2not only repairs the surface morphology of the active layer,but also increases the carrier concentration.When the thickness of the HfO_(2) film was 3 nm,the mobility of the device was doubled(14.9 cm^(2)·V^(-1)·s^(-1)→29.6 cm^(2)·V^(-1)·s^(-1)),and the device exhibited excellent logic device performance.This paper provides a simple and effective method to enhance the electrical performance of IGZO TFTs,offering new ideas and experimental foundation for research into high-performance metal oxide(MO)TFTs.展开更多
In this work,the incorporation of tantalum(Ta)into p-type metal-oxide(SnO_(x))semiconductor film is investigated to improve the electrical characteristics and suppress the fringe effect of thin film transistors(TFTs)....In this work,the incorporation of tantalum(Ta)into p-type metal-oxide(SnO_(x))semiconductor film is investigated to improve the electrical characteristics and suppress the fringe effect of thin film transistors(TFTs).The Ta-doped SnO_(x)(SnO_(x):Ta)film is deposited by radio-frequency(RF)magnetron sputtering with a Sn:Ta(3 at.%)target and thermally annealed at 270℃ for 30 min.Here,we observe that the SnO_(x):Ta film presents increased crystallinity,reduced defect density(3.25×10^(12)cm^(−2)·eV^(−1)),and widened bandgap(1.98 eV),in comparison with the undoped SnO_(x)film.As a result,the SnO_(x):Ta TFTs exhibit a lower off-state current(Ioff),an improved on/off current ratio(2.17×10^(4)),a remarkably decreased subthreshold swing(SS)by 41%,and enhanced device stability.Additionally,by introducing Ta dopants,the fringe effect as well as the impact of channel width-to-length ratio(W/L)on electrical performances of the p-type oxide TFTs can be effectively suppressed.These results shall contribute to further exploration and development of p-type SnO_(x)TFTs.展开更多
High-performance thin-film transistors （TFTs） with a low thermal budget are highly desired for flexible electronic applications. In this work, the TFTs with atomic layer deposited ZnO-channel/Al2O3-dielectric are fa...High-performance thin-film transistors （TFTs） with a low thermal budget are highly desired for flexible electronic applications. In this work, the TFTs with atomic layer deposited ZnO-channel/Al2O3-dielectric are fabricated under the maximum process temperature of 200℃. First, we investigate the effect of post-annealing environment such as N2, H2-N2 （4%） and O2 on the device performance, revealing that o2 annealing can greatly enhance the device performance. Further, we compare the influences of annealing temperature and time on the device performance. It is found that long anneMing at 200℃is equivalent to and even outperforms short annealing at 300℃. Excellent electrical characteristics of the TFTs are demonstrated after 02 anneMing at 200℃ for 35 rain, including a low off-current of 2.3 × 10-13 A, a small sub-threshold swing of 245 m V/dec, a large on/off current ratio of 7.6×10s, and a high electron effective mobility of 22.1cm2/V.s. Under negative gate bias stress at -10 V, the above devices show better electrical stabilities than those post-annealed at 300℃. Thus the fabricated high-performance ZnO TFT with a low thermal budget is very promising for flexible electronic applications.展开更多
The traditional von Neumann architecture has demonstrated inefficiencies in parallel computing and adaptive learn-ing,rendering it incapable of meeting the growing demand for efficient and high-speed computing.Neuromo...The traditional von Neumann architecture has demonstrated inefficiencies in parallel computing and adaptive learn-ing,rendering it incapable of meeting the growing demand for efficient and high-speed computing.Neuromorphic comput-ing with significant advantages such as high parallelism and ultra-low power consumption is regarded as a promising pathway to overcome the limitations of conventional computers and achieve the next-generation artificial intelligence.Among various neuromorphic devices,the artificial synapses based on electrolyte-gated transistors stand out due to their low energy consump-tion,multimodal sensing/recording capabilities,and multifunctional integration.Moreover,the emerging optoelectronic neuro-morphic devices which combine the strengths of photonics and electronics have demonstrated substantial potential in the neu-romorphic computing field.Therefore,this article reviews recent advancements in electrolyte-gated optoelectronic neuromor-phic transistors.First,it provides an overview of artificial optoelectronic synapses and neurons,discussing aspects such as device structures,operating mechanisms,and neuromorphic functionalities.Next,the potential applications of optoelectronic synapses in different areas such as artificial visual system,pain system,and tactile perception systems are elaborated.Finally,the current challenges are summarized,and future directions for their developments are proposed.展开更多
Complementary inverter is the basic unit for logic circuits,but the inverters based on full oxide thin-film transistors(TFTs)are still very limited.The next challenge is to realize complementary inverters using homoge...Complementary inverter is the basic unit for logic circuits,but the inverters based on full oxide thin-film transistors(TFTs)are still very limited.The next challenge is to realize complementary inverters using homogeneous oxide semiconduc-tors.Herein,we propose the design of complementary inverter based on full ZnO TFTs.Li-N dual-doped ZnO(ZnO:(Li,N))acts as the p-type channel and Al-doped ZnO(ZnO:Al)serves as the n-type channel for fabrication of TFTs,and then the complemen-tary inverter is produced with p-and n-type ZnO TFTs.The homogeneous ZnO-based complementary inverter has typical volt-age transfer characteristics with the voltage gain of 13.34 at the supply voltage of 40 V.This work may open the door for the development of oxide complementary inverters for logic circuits.展开更多
文摘This paper investigates the variation of electrical characteristic of indium gallium zinc oxide (IGZO) thin film transistors (TFTs) under gate bias stress. The devices are subjected to positive and negative gate bias stress for prolonged time periods. The effect of bias stress time and polarity on the transistor current equation is investigated and the underlying effects responsible for these variations are determined. Negative gate stress produces a positive shift in the threshold voltage. This can be noted as a variation from prior studies. Due to variation of power factor (n) from two, the integral method is implemented to extract threshold voltage (vt) and power factor (n). Effective, mobility (ueff), drain to source resistance (RDS) and constant k' is also extracted from the device characteristics. The unstressed value of n is deter-mined to be 2.5. The power factor increases with gate bias stress time. The distribution of states in the conduction band is revealed by the variation in power factor.
基金financially supported by the National Natural Science Foundation of China(Nos.52272214,52372082,52466013,52373184,and U24A20660)Jiangxi Provincial Natural Science Foundation(Nos.20242BAB26059,20232BAB204032,20252BAC200290,20252BEJ730349,and 20252BAC240326)Doctoral Start-Up Fund of Jiangxi Science&Technology Normal University(No.2024BSQD16)。
文摘Glucose,ascorbic acid(AA),uric acid(UA),and dopamine(DA)are vital biomarkers whose dynamic concentrations correlate with critical diseases;however,multiplexed detection remains challenging for conventional electrochemical sensors because of their limited sensitivity and selectivity.Here,we present a millimeter-scale all-poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate)(PEDOT:PSS)organic electrochemical transistor(OECT)platform that integrates dual-mode sensing with enzyme/metal-free operation for ultrasensitive biomarker monitoring.By engineering polycrystalline PEDOT:PSS channels via H_2 SO_4 post-treatment,the device achieves record-high conductivity(about(2312.0±29.9)S·cm^(–1)),maximum transconductance(about(2.82±0.12)mS),and on/off ratio(about 210.0±7.8),enabling signal amplification at low gate voltages.The dual-mode strategy combines the selectivity of electrochemistry with the sensitivity of OECTs,realizing simultaneous detection of glucose,AA,UA,and DA with clinical-level sensitivity:detection limits down to 8 nmol·L^(–1)(glucose),0.5 nmol·L^(–1)(AA),5 nmol·L^(–1)(DA),and 0.5 nmol·L^(–1)(UA).Validation using human urine samples yielded recovery rates of 94%–114%.This flexible sensing platform provides a new pathway for the development of wearable biosensors for precision diagnostics.
基金supported by the Natural Science Foundation of Guangdong Province,China (No.2025A1515011654)the National Natural Science Foundation of China (No.22090053)+3 种基金the Fundamental Research Funds for National Universities,China University of Geosciences (Wuhan)support from the program of China Scholarships Council (No.202406410155)Young Elite Scientists Sponsorship Program by CAST-Doctoral Student Special Plansupport from the S&T Special Program of Huzhou (No.2024GZ07)。
文摘Field-effect nanofluidic transistors(FENTs),biomimicking the structure and functionality of neuron,act as biological transistors with the ability to gate switching responses to external stimuli.The switching ratio has been verified to evaluate the performance of FENTs,but until recently,the response time,another crucial indicator,has been ignored.Employing finite-element method,we investigated the relationship among gate charge,switching ratio and response time by divisionally manipulating gate charge,including entrance surface and the surface of confinement space,for ion transport to optimize switching capability.The dual-split gate charge on FENTs exhibits synergistic effect on switching response.Based on the two regional gate charge on FENTs,multivalence ions in lower concentration,high aspect ratio and single channel show higher switching ratio but longer response time compared to monovalent ions.The findings highlight the necessity of balancing these two signals in FENTs and offer insights for optimizing their design and expanding applications to dual-signal-detection iontronics.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11775191,61404115,61434006,and 11475256)the Development Fund for Outstanding Young Teachers in Zhengzhou University of China(Grant No.1521317004)the Doctoral Student Overseas Study Program of Zhengzhou University,China
文摘The performance damage mechanism of InP-based high electron mobility transistors(HEMTs) after proton irradiation has been investigated comprehensively through induced defects.The effects of the defect type, defect energy level with respect to conduction band ET, and defect concentration on the transfer and output characteristics of the device are discussed based on hydrodynamic model and Shockley–Read–Hall recombination model.The results indicate that only acceptorlike defects have a significant influence on device operation.Meanwhile, as defect energy level ETshifts away from conduction band, the drain current decreases gradually and finally reaches a saturation value with ETabove 0.5 eV.This can be attributed to the fact that at sufficient deep level, acceptor-type defects could not be ionized any more.Additionally,the drain current and transconductance degrade more severely with larger acceptor concentration.These changes of the electrical characteristics with proton radiation could be accounted for by the electron density reduction in the channel region from induced acceptor-like defects.
基金Project supported by the National Key R&D Program of China(Grant No.2016YFB0400100)the National Natural Science Foundation of China(Grant No.91850112)+3 种基金the Natural Science Foundation of Jiangsu Province,China(Grant No.BK20161401)the Priority Academic Program Development of Jiangsu Higher Education Institutions,Chinathe Science and Technology Project of State Grid Corporation of China(Grant No.SGSDDK00KJJS1600071)the Fundamental Research Funds for the Central Universities,China(Grant No.14380098)
文摘Self-heating effect in amorphous InGaZnO thin-film transistors remains a critical issue that degrades device performance and stability, hindering their wider applications. In this work, pulsed current–voltage analysis has been applied to explore the physics origin of self-heating induced degradation, where Joule heat is shortly accumulated by drain current and dissipated in repeated time cycles as a function of gate bias. Enhanced positive threshold voltage shift is observed at reduced heat dissipation time, higher drain current, and increased gate width. A physical picture of Joule heating assisted charge trapping process has been proposed and then verified with pulsed negative gate bias stressing scheme, which could evidently counteract the self-heating effect through the electric-field assisted detrapping process. As a result, this pulsed gate bias scheme with negative quiescent voltage could be used as a possible way to actively suppress self-heating related device degradation.
基金supported in part by the National Natural Science Foundation of China(62404110,62274033)Natural Science Foundation of Jiangsu Province(BK20221453)+1 种基金Fundamental Research Funds for the Central UniversitiesNatural Science Research Start-up Foundation of Recruiting Talents of Nanjing University of Posts and Telecommunications(NY223159)。
文摘In this work,we demonstrated the InSnO(ITO)TFTs passivated with SiO_(2)via the PECVD process compatible with large-area production for the first time.The passivated ITO TFTs with various channel thicknesses(t_(ch)=4,5,6 nm)exhibit excellent electrical performance and superior uniformity.The reliability properties of ITO TFTs were evaluated in detail under positive bias stress(PBS)conditions before and after passivation.Compared to the devices without passivation,the passivated devices have only 50%threshold voltage degradation(ΔV_(th))and 50%newly generated traps due to excellent isolation of the ambient atmosphere.The negligible performance degradation of ITO TFTs with passivation during negative bias stress(NBS)and negative bias temperature stress(NBTS)verifies the outstanding immunity to the water vapor of the SiO_(2)passivation layer.Overall,the ITO TFT with the t_(ch)of 6 nm and with SiO_(2)passivation exhibits the best performance in terms of electrical properties,uniformity,and reliability,which is promising in large-area production.
文摘Displacement damage induced by neutron irradiation in China Spallation Neutron Source(CSNS) is studied on bipolar transistors with lateral PNP, substrate PNP, and vertical NPN configurations, respectively. Comparison of the effects on different type transistors is conducted based on displacement damage factor, and the differences are analyzed through minority carrier lifetime calculation and structure analysis. The influence of CSNS neutrons irradiation on the lateral PNP transistors is analyzed by the gate-controlled method, including the oxide charge accumulation, surface recombine velocity,and minority carrier lifetime. The results indicate that the total ionizing dose in CSNS neutron radiation environment is negligible in this study. The displacement damage factors based on 1-MeV equivalent neutron flux of different transistors are consistent between Xi’an pulse reactor(XAPR) and CSNS.
文摘Nitrogen doping is a promising way to modulate the electrical properties of graphene to realize graphene-based electronics and promise fascinating properties and applications.Herein,we report a method to noncovalently assembly titanium(Ⅳ) bis(ammoniumlactato) dihydroxide(Ti complex) on nitrogen-doped graphene to create a reliable hybrids which can be used as a reversible chemical induced switching.As the adsorption and desorption of Ti complex in sequential treatments,the conductance of the nitrogen-doped graphene transistors was finely modulated.Control experiments with pristine graphene clearly demonstrated the important effort of the nitrogen in this chemical sensor.Under optimized conditions,nitrogen-doped graphene transistors open up new ways to develop multifunctional devices with high sensitivity.
基金Project supported by the National Key R&D Program of China(Grant No.2016YFA0200503)the National Natural Science Foundation of China(Grant No.61327813)
文摘We demonstrate transitions of hopping behaviors for delocalized electrons through the discrete dopant-induced quantum dots in n-doped silicon junctionless nanowire transistors by the temperature-dependent conductance characteristics.There are two obvious transition platforms within the critical temperature regimes for the experimental conductance data,which are extracted from the unified transfer characteristics for different temperatures at the gate voltage positions of the initial transconductance gm peak in Vg1 and valley in Vg2. The crossover temperatures of the electron hopping behaviors are analytically determined by the temperature-dependent conductance at the gate voltages Vg1 and Vg2. This finding provides essential evidence for the hopping electron behaviors under the influence of thermal activation and long-range Coulomb interaction.
基金supported financially by National key Research and Development Program under Grant 2021YFB3600802Shenzhen Municipal Scientific Program under Grant KJZD20230923114111021。
文摘Besides the common short-channel effect(SCE)of threshold voltage(V_(th))roll-off during the channel length(L)downscaling of In GaZnO(IGZO)thin-film transistors(TFTs),an opposite V_(th)roll-up was reported in this work.Both roll-off and roll-up effects of Vth were comparatively investigated on IGZO transistors with varied gate insulator(GI),source/drain(S/D),and device architecture.For IGZO transistors with thinner GI,the SCE was attenuated due to the enhanced gate controllability over the variation of channel carrier concentration,while the Vth roll-up became more noteworthy.The latter was found to depend on the relative ratio of S/D series resistance(R_(SD))over channel resistance(R_(CH)),as verified on transistors with different S/D.Thus,an ideal S/D engineering with small R_(SD)but weak dopant diffusion is highly expected during the downscaling of L and GI in IGZO transistors.
基金supported by the National Key R&D Program of China(No.2023YFC3707201)the National Natural Science Foundation of China(No.52320105003)+2 种基金the Informatization Plan of Chinese Academy of Sciences(No.CAS-WX2023PY-0103)the Fundamental Research Funds for the Central Universities(No.E3ET1803)sponsored by the Alliance of International Science Organizations(ANSO)scholarship for young talents.
文摘A sensor,serving as a transducer,produces a quantifiable output in response to a predetermined input stimulus,which may be of a chemical or physical nature.The field of gas detection has experienced a substantial surge in research activity,attributable to the diverse functionalities and enhanced accessibility of advanced active materials.In this work,recent advances in gas sensors,specifically those utilizing Field Effect Transistors(FETs),are summarized,including device configurations,response characteristics,sensor materials,and application domains.In pursuing high-performance artificial olfactory systems,the evolution of FET gas sensors necessitates their synchronization with material advancements.These materials should have large surface areas to enhance gas adsorption,efficient conversion of gas input to detectable signals,and strong mechanical qualities.The exploration of gas-sensitive materials has covered diverse categories,such as organic semiconductor polymers,conductive organic compounds and polymers,metal oxides,metal-organic frameworks,and low-dimensional materials.The application of gas sensing technology holds significant promise in domains such as industrial safety,environmental monitoring,and medical diagnostics.This comprehensive review thoroughly examines recent progress,identifies prevailing technical challenges,and outlines prospects for gas detection technology utilizing field effect transistors.The primary aim is to provide a valuable reference for driving the development of the next generation of gas-sensitive monitoring and detection systems characterized by improved sensitivity,selectivity,and intelligence.
基金supported by the National Key R&D Plan of China(Grant No.2023YFB3210400)the National Natural Science Foundation of China(No.62174101)+2 种基金the Major Scientific and Technological Innovation Project of Shandong Province(2021CXGC010603)the Fundamental Research Funds of Shandong University(2020QNQT001)Collaborative Innovation Center of Technology and Equipment for Biological Diagnosis and Therapy in Universities of Shandong,Collaborative Innovation Center of Technology and Equipment for Biological Diagnosis and Therapy in Universities of Shandong,the Natural Science Foundation of Qingdao-Original exploration project(No.24-4-4-zrjj-139-jch).
文摘Flexible electronics are transforming our lives by making daily activities more convenient.Central to this innovation are field-effect transistors(FETs),valued for their efficient signal processing,nanoscale fabrication,low-power consumption,fast response times,and versatility.Graphene,known for its exceptional mechanical properties,high electron mobility,and biocompatibility,is an ideal material for FET channels and sensors.The combination of graphene and FETs has given rise to flexible graphene field-effect transistors(FGFETs),driving significant advances in flexible electronics and sparked a strong interest in flexible biomedical sensors.Here,we first provide a brief overview of the basic structure,operating mechanism,and evaluation parameters of FGFETs,and delve into their material selection and patterning techniques.The ability of FGFETs to sense strains and biomolecular charges opens up diverse application possibilities.We specifically analyze the latest strategies for integrating FGFETs into wearable and implantable flexible biomedical sensors,focusing on the key aspects of constructing high-quality flexible biomedical sensors.Finally,we discuss the current challenges and prospects of FGFETs and their applications in biomedical sensors.This review will provide valuable insights and inspiration for ongoing research to improve the quality of FGFETs and broaden their application prospects in flexible biomedical sensing.
基金Project supported by the National Natural Science Foundation of China(Grant No.61574048)the Pearl River Science and Technology Nova Program of Guangzhou City,China(Grant No.201710010172)+2 种基金the International Science and Technology Cooperation Program of Guangzhou City(Grant No.201807010006)the International Cooperation Program of Guangdong Province,China(Grant No.2018A050506044)the Opening Fund of Key Laboratory of Silicon Device Technology,China(Grant No.KLSDTJJ2018-6)
文摘The instability of p-channel low-temperature polycrystalline silicon thin film transistors(poly-Si TFTs)is investigated under negative gate bias stress(NBS)in this work.Firstly,a series of negative bias stress experiments is performed,the significant degradation behaviors in current-voltage characteristics are observed.As the stress voltage decreases from-25 V to-37 V,the threshold voltage and the sub-threshold swing each show a continuous shift,which is induced by gate oxide trapped charges or interface state.Furthermore,low frequency noise(LFN)values in poly-Si TFTs are measured before and after negative bias stress.The flat-band voltage spectral density is extracted,and the trap concentration located near the Si/SiO2 interface is also calculated.Finally,the degradation mechanism is discussed based on the current-voltage and LFN results in poly-Si TFTs under NBS,finding out that Si-OH bonds may be broken and form Si*and negative charge OH-under negative bias stress,which is demonstrated by the proposed negative charge generation model.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.61704008 and 11574362)。
文摘We have successfully prepared GaN based high electron mobility transistors(HEMTs)on metallic substrates transferred from silicon substrates by electroplating technique.GaN HEMTs on Cu substrates are demonstrated to basically have the same good electric characteristics as the chips on Si substrates.Furthermore,the better heat dissipation of HEMTs on Cu substrates compared to HEMTs on Si substrates is clearly observed by thermoreflectance imaging,showing the promising potential for very high-power and high-temperature operation.This work shows the outstanding ability of HEMT chips on Cu substrates for solving the self-heating effect with the advantages of process simplicity,high yield,and low production requirement.
基金financial support by the self-supporting project of Pazhou Lab(No.PZL2023ZZ0011)by National Key R&D Program of China(No.2019YFA0904801).
文摘Rapid development of artificial intelligence requires the implementation of hardware systems with bioinspired parallel information processing and presentation and energy efficiency.Electrolyte-gated organic transistors(EGOTs)offer significant advantages as neuromorphic devices due to their ultra-low operation voltages,minimal hardwired connectivity,and similar operation environment as electrophysiology.Meanwhile,ionic–electronic coupling and the relatively low elastic moduli of organic channel materials make EGOTs suitable for interfacing with biology.This review presents an overview of the device architectures based on organic electrochemical transistors and organic field-effect transistors.Furthermore,we review the requirements of low energy consumption and tunable synaptic plasticity of EGOTs in emulating biological synapses and how they are affected by the organic materials,electrolyte,architecture,and operation mechanism.In addition,we summarize the basic operation principle of biological sensory systems and the recent progress of EGOTs as a building block in artificial systems.Finally,the current challenges and future development of the organic neuromorphic devices are discussed.
基金Project supported by the National Natural Science Foundation of China(Grant No.62441407)the Natural Science Basic Research Program of Shaanxi(Grant No.2024JCYBQN-0631)+1 种基金the Natural Science Foundation of Shaanxi Provincial Department of Education(Grant No.23JK0482)the Shaanxi Province Key R&D Program General Project-Industrial Field(Grant No.2024GX-YBXM-085)。
文摘The enhancement of mobility has always been a research focus in the field of thin-film transistors(TFTs).In this paper,we report a method using ultra-thin HfO2to improve the electrical performance of indium gallium zinc oxide(IGZO)TFTs.HfO2not only repairs the surface morphology of the active layer,but also increases the carrier concentration.When the thickness of the HfO_(2) film was 3 nm,the mobility of the device was doubled(14.9 cm^(2)·V^(-1)·s^(-1)→29.6 cm^(2)·V^(-1)·s^(-1)),and the device exhibited excellent logic device performance.This paper provides a simple and effective method to enhance the electrical performance of IGZO TFTs,offering new ideas and experimental foundation for research into high-performance metal oxide(MO)TFTs.
基金supported in part by National Key R&D Program of China(Grant No.2022YFE0141500)National Natural Science Foundation of China(Grant Nos.62004065 and 62274059).
文摘In this work,the incorporation of tantalum(Ta)into p-type metal-oxide(SnO_(x))semiconductor film is investigated to improve the electrical characteristics and suppress the fringe effect of thin film transistors(TFTs).The Ta-doped SnO_(x)(SnO_(x):Ta)film is deposited by radio-frequency(RF)magnetron sputtering with a Sn:Ta(3 at.%)target and thermally annealed at 270℃ for 30 min.Here,we observe that the SnO_(x):Ta film presents increased crystallinity,reduced defect density(3.25×10^(12)cm^(−2)·eV^(−1)),and widened bandgap(1.98 eV),in comparison with the undoped SnO_(x)film.As a result,the SnO_(x):Ta TFTs exhibit a lower off-state current(Ioff),an improved on/off current ratio(2.17×10^(4)),a remarkably decreased subthreshold swing(SS)by 41%,and enhanced device stability.Additionally,by introducing Ta dopants,the fringe effect as well as the impact of channel width-to-length ratio(W/L)on electrical performances of the p-type oxide TFTs can be effectively suppressed.These results shall contribute to further exploration and development of p-type SnO_(x)TFTs.
基金Supported by the National Natural Science Foundation of China under Grant Nos 61474027 and 61376008
文摘High-performance thin-film transistors （TFTs） with a low thermal budget are highly desired for flexible electronic applications. In this work, the TFTs with atomic layer deposited ZnO-channel/Al2O3-dielectric are fabricated under the maximum process temperature of 200℃. First, we investigate the effect of post-annealing environment such as N2, H2-N2 （4%） and O2 on the device performance, revealing that o2 annealing can greatly enhance the device performance. Further, we compare the influences of annealing temperature and time on the device performance. It is found that long anneMing at 200℃is equivalent to and even outperforms short annealing at 300℃. Excellent electrical characteristics of the TFTs are demonstrated after 02 anneMing at 200℃ for 35 rain, including a low off-current of 2.3 × 10-13 A, a small sub-threshold swing of 245 m V/dec, a large on/off current ratio of 7.6×10s, and a high electron effective mobility of 22.1cm2/V.s. Under negative gate bias stress at -10 V, the above devices show better electrical stabilities than those post-annealed at 300℃. Thus the fabricated high-performance ZnO TFT with a low thermal budget is very promising for flexible electronic applications.
基金supported by the Hunan Science Fund for Distinguished Young Scholars(2023JJ10069)the National Natural Science Foundation of China(52172169)the Project of State Key Laboratory of Precision Manufacturing for Extreme Service Performance,Central South University(ZZYJKT2024-02).
文摘The traditional von Neumann architecture has demonstrated inefficiencies in parallel computing and adaptive learn-ing,rendering it incapable of meeting the growing demand for efficient and high-speed computing.Neuromorphic comput-ing with significant advantages such as high parallelism and ultra-low power consumption is regarded as a promising pathway to overcome the limitations of conventional computers and achieve the next-generation artificial intelligence.Among various neuromorphic devices,the artificial synapses based on electrolyte-gated transistors stand out due to their low energy consump-tion,multimodal sensing/recording capabilities,and multifunctional integration.Moreover,the emerging optoelectronic neuro-morphic devices which combine the strengths of photonics and electronics have demonstrated substantial potential in the neu-romorphic computing field.Therefore,this article reviews recent advancements in electrolyte-gated optoelectronic neuromor-phic transistors.First,it provides an overview of artificial optoelectronic synapses and neurons,discussing aspects such as device structures,operating mechanisms,and neuromorphic functionalities.Next,the potential applications of optoelectronic synapses in different areas such as artificial visual system,pain system,and tactile perception systems are elaborated.Finally,the current challenges are summarized,and future directions for their developments are proposed.
基金supported by Zhejiang Provincial Natural Science Foundation of China(No.LZ24E020001).
文摘Complementary inverter is the basic unit for logic circuits,but the inverters based on full oxide thin-film transistors(TFTs)are still very limited.The next challenge is to realize complementary inverters using homogeneous oxide semiconduc-tors.Herein,we propose the design of complementary inverter based on full ZnO TFTs.Li-N dual-doped ZnO(ZnO:(Li,N))acts as the p-type channel and Al-doped ZnO(ZnO:Al)serves as the n-type channel for fabrication of TFTs,and then the complemen-tary inverter is produced with p-and n-type ZnO TFTs.The homogeneous ZnO-based complementary inverter has typical volt-age transfer characteristics with the voltage gain of 13.34 at the supply voltage of 40 V.This work may open the door for the development of oxide complementary inverters for logic circuits.
