Aluminium doped tin oxide films have been deposited onto glass substrates by using a simplified and low cost spray pyrolysis technique. The AI doping level varies between 0 and 30 at.% in the step of 5 at.%. The resis...Aluminium doped tin oxide films have been deposited onto glass substrates by using a simplified and low cost spray pyrolysis technique. The AI doping level varies between 0 and 30 at.% in the step of 5 at.%. The resistivity （p） is the minimum （0.38 Ω cm） for 20 at.% of AI doping. The possible mechanism behind the phenomenal zig-zag variation in resistivity with respect to AI doping is discussed in detail. The nature of conductivity changes from n-type to p-type when the AI doping level is 10 at.%. The results show that 20 at.% is the optimum doping level for good quality p-type SnO2：AI films suitable for transparent electronic devices.展开更多
Flexible and transparent electronics enters into a new era of electronic technologies.Ubiquitous applications involve wearable electronics,biosensors,flexible transparent displays,radio-frequency identifications（RFID...Flexible and transparent electronics enters into a new era of electronic technologies.Ubiquitous applications involve wearable electronics,biosensors,flexible transparent displays,radio-frequency identifications（RFIDs）,etc.Zinc oxide（ZnO） and relevant materials are the most commonly used inorganic semiconductors in flexible and transparent devices,owing to their high electrical performances,together with low processing temperatures and good optical transparencies.In this paper,we review recent advances in flexible and transparent thin-film transistors（TFTs） based on ZnO and relevant materials.After a brief introduction,the main progress of the preparation of each component（substrate,electrodes,channel and dielectrics） is summarized and discussed.Then,the effect of mechanical bending on electrical performance is highlighted.Finally,we suggest the challenges and opportunities in future investigations.展开更多
Transparent, flexible electronic skin holds a wide range of applications in robotics, humanmachine interfaces, artificial intelligence, prosthetics, and health monitoring. Silver nanowire are mechanically flexible and...Transparent, flexible electronic skin holds a wide range of applications in robotics, humanmachine interfaces, artificial intelligence, prosthetics, and health monitoring. Silver nanowire are mechanically flexible and robust, which exhibit great potential in transparent and electricconducting thin film. Herein, we report on a silver-nanowire spray-coating and electrodemicrostructure replicating strategy to construct a transparent, flexible, and sensitive electronic skin device. The electronic skin device shows highly sensitive piezo-capacitance response to pressure. It is found that micropatterning the surface of dielectric layer polyurethane elastomer by replicating from microstructures of natural-existing surfaces such as lotus leaf, silk, and frosted glass can greatly enhance the piezo-capacitance performance of the device. The microstructured pressure sensors based on silver nanowire exhibit good transparency, excellent flexibility, wide pressure detection range （0-150 kPa）, and high sensitivity （1.28 kPa-1）.展开更多
Ga doped ZnO （OZO）/Cu grid/GZO transparent conductive electrode （TCE） structures were fabricated at room temperature （RT） by using electron beam evaporation （EBE） for the Cu grids and RF magnetron sputtering f...Ga doped ZnO （OZO）/Cu grid/GZO transparent conductive electrode （TCE） structures were fabricated at room temperature （RT） by using electron beam evaporation （EBE） for the Cu grids and RF magnetron sputtering for the GZO layers. In this work, we investigated the electrical and optical characteristics of GZO/Cu grid/GZO multilayer electrode for thin film solar cells by using evaporated Cu grid and sputtered GZO thin films to enhance the optical transparency without significantly affecting their conductivity. The optical transmittance and sheet resistance of GZO/Cu grid/GZO multilayer are higher than those of GZO/Cu film/GZO multilayer independent of Cu grid separation distance and increase with increasing Cu grid separation distances. The calculation of both transmittance and sheet resistance of GZO/Cu grid] GZO multilayer was based on Cu filling factor correlated with the geometry of Cu grid. The calculated values for the transmittance and sheet resistance of the GZO/Cu grid/GZO multilayer were similar to the experimentally observed ones. The highest figure of merit ФTc is 5.18× 10^-3Ω^-1 for the GZO/Cu grid] GZO multilayer with Cu grid separation distance of 1 mm was obtained, in this case, the transmittance and resistivity were 82.72% and 2.17 × 10 ^-4Ωcm, respectively. The transmittance and resistivity are accentahle for nractical thin film snlar cell annlicatinn~展开更多
Prticle-in-cell（PIC） simulations demonstrated that,when the relativistic magnetron with diffraction output（MDO） is applied with a 410 kV voltage pulse,or when the relativistic magnetron with radial output is appli...Prticle-in-cell（PIC） simulations demonstrated that,when the relativistic magnetron with diffraction output（MDO） is applied with a 410 kV voltage pulse,or when the relativistic magnetron with radial output is applied with a 350 kV voltage pulse,electrons emitted from the cathode with high energy will strike the anode block wall.The emitted secondary electrons and backscattered electrons affect the interaction between electrons and RF fields induced by the operating modes,which decreases the output power in the radial output relativistic magnetron by about 15%（10%for the axial output relativistic magnetron）,decreases the anode current by about 5%（5%for the axial output relativistic magnetron）,and leads to a decrease of electronic efficiency by 8%（6%for the axial output relativistic magnetron）.The peak value of the current formed by secondary and backscattered current equals nearly half of the amplitude of the anode current,which may help the growth of parasitic modes when the applied magnetic field is near the critical magnetic field separating neighboring modes.Thus,mode competition becomes more serious.展开更多
An n-type channel transparent thin film field-effect transistor(FET)using a top-gate configuration on a sapphire substrate is presented.ZnO:Li film was used as a channel,and MgF_(2)film as a gate insulator.Measurement...An n-type channel transparent thin film field-effect transistor(FET)using a top-gate configuration on a sapphire substrate is presented.ZnO:Li film was used as a channel,and MgF_(2)film as a gate insulator.Measurements showed that ZnO:Li films are ferroelectrics with spontaneous polarization P_(s)=1-5μC/cm^(2)and coercive field E_(c)=5-10kV/cm.The dependences of drain-source current on drain-source voltage at various gate-source voltages in two antiparallel P_(s)states were measured and the values of field-effect mobility and threshold voltage were determined for two Ps states are as follows:(a)μ=1.5 cm2/Vs,U_(th)=30V;(b)μ=1.7 cm^(2)/Vs,U_(th)=23 V.Thus,P_(s)switching leads to a change in FET channel parameters.Results can be used to create a bistable or,more precisely,digital FET.展开更多
Ti_(3)C_(2) MXe ne servi ng as superior electrical con ductors prese nts more specific performa nee such as tran spar ency,con ductivity tha n gold(Au),and even could form a heterostructure with active materials of th...Ti_(3)C_(2) MXe ne servi ng as superior electrical con ductors prese nts more specific performa nee such as tran spar ency,con ductivity tha n gold(Au),and even could form a heterostructure with active materials of the functional devices.Here,a Ti_(3)C_(2) MXene-Te microplate van der Waals heterostructure based tran spare nt near-i nfrared photodetector(PD)is exploited.展开更多
Graphene with an exceptional combination of electronic, optical and outstanding mechanical features has been proved to lead a completely different kind of 2-D electronics. The most exciting feature of graphene is its ...Graphene with an exceptional combination of electronic, optical and outstanding mechanical features has been proved to lead a completely different kind of 2-D electronics. The most exciting feature of graphene is its ultra-thin thickness, that can be conformally contacted to any kind of rough surface without losing much of its transparency and conductivity. Graphene has been explored demonstrating various prototype flexible electronic applications, however, its potentiality has been proven wherever transparent conductive electrodes（TCEs） are needed in a flexible, stretchable format. Graphene-based TCEs in flexible electronic applications showed greatly superior performance over their conventionally available competitor indium tin oxide（ITO）. Moreover, enormous applications have been emerging, especially in wearable devices that can be potentially used in our daily life as well as in biomedical areas. However, the production of high-quality, defect-free large area graphene is still a challenge and the main hurdle in the commercialization of flexible and wearable products. The objective of the present review paper is to summarize the progress made so far in graphene-based flexible and wearable applications. The current developments including challenges and future perspectives arc also highlighted.展开更多
Light-mediated therapeutics have attracted considerable attention as a method for the treatment of ophthalmologic diseases,such as age-related macular degeneration,because of their non-invasiveness and the effectivene...Light-mediated therapeutics have attracted considerable attention as a method for the treatment of ophthalmologic diseases,such as age-related macular degeneration,because of their non-invasiveness and the effectiveness to ameliorate the oxidative stress of retinal cells.However,the current phototherapeutic devices are opaque,bulky,and tethered forms,so they are not feasible for use in continuous treatment during the patient’s daily life.Herein,we report wireless,wearable phototherapeutic devices with red light-emitting diodes for continuous treatments.Red light-emitting diodes were formed to be conformal to three-dimensional surfaces of glasses and contact lenses.Furthermore,fabricated light-emitting diodes had either transparency or a miniaturized size so that the user’s view is not obstructed.Also,these devices were operated wirelessly with control of the light intensity.In addition,in-vitro and in-vivo tests using human retinal epithelial cells and a live rabbit demonstrated the effectiveness and reliable operation as phototherapeutic devices.展开更多
Background Gas Electron Multiplier(GEM)detectors are widely used for high-energy physics experiments,such as the triple-GEM detector installed in CMS,due to their excellent performance.A quadruple-GEM detector is rega...Background Gas Electron Multiplier(GEM)detectors are widely used for high-energy physics experiments,such as the triple-GEM detector installed in CMS,due to their excellent performance.A quadruple-GEM detector is regarded as the candidate for the upgrade projects of the High Luminosity LHC(HL-LHC).Method In this paper,key performance characteristics of quadruple-GEM detectors are studied in detail based on Monte Carlo simulation using the Garfield++and ANSYS software packages.The parameterization method is adopted.Result The spatial and time resolution,effective gain,efficiency,and electron transparency are obtained via simulation for different detector geometries and operating conditions.We create a quadruple-GEM structure that meets the geometric requirements of the CMS endcap muon detectors.Conclusion These studies help to understand the physical mechanisms of GEM detectors and provide references for the detector design,operating condition optimization and technical scheme selection in future applications.展开更多
基金Financial support from the University Grants Commission ofIndia through the Major Research Project(F.No.40-28/2011(SR))the DST Grant(D.O.No.SR/S2/CMP-35/2004)
文摘Aluminium doped tin oxide films have been deposited onto glass substrates by using a simplified and low cost spray pyrolysis technique. The AI doping level varies between 0 and 30 at.% in the step of 5 at.%. The resistivity （p） is the minimum （0.38 Ω cm） for 20 at.% of AI doping. The possible mechanism behind the phenomenal zig-zag variation in resistivity with respect to AI doping is discussed in detail. The nature of conductivity changes from n-type to p-type when the AI doping level is 10 at.%. The results show that 20 at.% is the optimum doping level for good quality p-type SnO2：AI films suitable for transparent electronic devices.
基金Project supported by the National Natural Science Foundation of China(Grants Nos.61306011,11274366,51272280,11674405,and 11675280)
文摘Flexible and transparent electronics enters into a new era of electronic technologies.Ubiquitous applications involve wearable electronics,biosensors,flexible transparent displays,radio-frequency identifications（RFIDs）,etc.Zinc oxide（ZnO） and relevant materials are the most commonly used inorganic semiconductors in flexible and transparent devices,owing to their high electrical performances,together with low processing temperatures and good optical transparencies.In this paper,we review recent advances in flexible and transparent thin-film transistors（TFTs） based on ZnO and relevant materials.After a brief introduction,the main progress of the preparation of each component（substrate,electrodes,channel and dielectrics） is summarized and discussed.Then,the effect of mechanical bending on electrical performance is highlighted.Finally,we suggest the challenges and opportunities in future investigations.
基金This work was supported by the National Natural Science Foundation of China （No.61674078） and Dongrun- Yau Science Silver Award （Chemistry）.
文摘Transparent, flexible electronic skin holds a wide range of applications in robotics, humanmachine interfaces, artificial intelligence, prosthetics, and health monitoring. Silver nanowire are mechanically flexible and robust, which exhibit great potential in transparent and electricconducting thin film. Herein, we report on a silver-nanowire spray-coating and electrodemicrostructure replicating strategy to construct a transparent, flexible, and sensitive electronic skin device. The electronic skin device shows highly sensitive piezo-capacitance response to pressure. It is found that micropatterning the surface of dielectric layer polyurethane elastomer by replicating from microstructures of natural-existing surfaces such as lotus leaf, silk, and frosted glass can greatly enhance the piezo-capacitance performance of the device. The microstructured pressure sensors based on silver nanowire exhibit good transparency, excellent flexibility, wide pressure detection range （0-150 kPa）, and high sensitivity （1.28 kPa-1）.
基金support of the key project of the National Natural Science Foundation of China under Grant Nos.91333203 and 51172204the Program for Innovative Research Team in University of Ministry of Education of China under Grant No.IRT13037the Zhejiang Provincial Department of Science and Technology of China under Grant No.2010R50020
文摘Ga doped ZnO （OZO）/Cu grid/GZO transparent conductive electrode （TCE） structures were fabricated at room temperature （RT） by using electron beam evaporation （EBE） for the Cu grids and RF magnetron sputtering for the GZO layers. In this work, we investigated the electrical and optical characteristics of GZO/Cu grid/GZO multilayer electrode for thin film solar cells by using evaporated Cu grid and sputtered GZO thin films to enhance the optical transparency without significantly affecting their conductivity. The optical transmittance and sheet resistance of GZO/Cu grid/GZO multilayer are higher than those of GZO/Cu film/GZO multilayer independent of Cu grid separation distance and increase with increasing Cu grid separation distances. The calculation of both transmittance and sheet resistance of GZO/Cu grid] GZO multilayer was based on Cu filling factor correlated with the geometry of Cu grid. The calculated values for the transmittance and sheet resistance of the GZO/Cu grid/GZO multilayer were similar to the experimentally observed ones. The highest figure of merit ФTc is 5.18× 10^-3Ω^-1 for the GZO/Cu grid] GZO multilayer with Cu grid separation distance of 1 mm was obtained, in this case, the transmittance and resistivity were 82.72% and 2.17 × 10 ^-4Ωcm, respectively. The transmittance and resistivity are accentahle for nractical thin film snlar cell annlicatinn~
基金supported by National Natural Science Foundation of China(No.61302010)the Foundation of Science and Technology on High Power Microwave Laboratory,Central University Foundation(2013KW07)Work at the University of New Mexico in USA was supportedby ONR Grant N00014-13-1-0565
文摘Prticle-in-cell（PIC） simulations demonstrated that,when the relativistic magnetron with diffraction output（MDO） is applied with a 410 kV voltage pulse,or when the relativistic magnetron with radial output is applied with a 350 kV voltage pulse,electrons emitted from the cathode with high energy will strike the anode block wall.The emitted secondary electrons and backscattered electrons affect the interaction between electrons and RF fields induced by the operating modes,which decreases the output power in the radial output relativistic magnetron by about 15%（10%for the axial output relativistic magnetron）,decreases the anode current by about 5%（5%for the axial output relativistic magnetron）,and leads to a decrease of electronic efficiency by 8%（6%for the axial output relativistic magnetron）.The peak value of the current formed by secondary and backscattered current equals nearly half of the amplitude of the anode current,which may help the growth of parasitic modes when the applied magnetic field is near the critical magnetic field separating neighboring modes.Thus,mode competition becomes more serious.
基金supported by the Science Committee of RA in the frames of the research project N 21T-1C150.
文摘An n-type channel transparent thin film field-effect transistor(FET)using a top-gate configuration on a sapphire substrate is presented.ZnO:Li film was used as a channel,and MgF_(2)film as a gate insulator.Measurements showed that ZnO:Li films are ferroelectrics with spontaneous polarization P_(s)=1-5μC/cm^(2)and coercive field E_(c)=5-10kV/cm.The dependences of drain-source current on drain-source voltage at various gate-source voltages in two antiparallel P_(s)states were measured and the values of field-effect mobility and threshold voltage were determined for two Ps states are as follows:(a)μ=1.5 cm2/Vs,U_(th)=30V;(b)μ=1.7 cm^(2)/Vs,U_(th)=23 V.Thus,P_(s)switching leads to a change in FET channel parameters.Results can be used to create a bistable or,more precisely,digital FET.
基金This work was supported by the National Natural Science Foundation of China(No.61888102).
文摘Ti_(3)C_(2) MXe ne servi ng as superior electrical con ductors prese nts more specific performa nee such as tran spar ency,con ductivity tha n gold(Au),and even could form a heterostructure with active materials of the functional devices.Here,a Ti_(3)C_(2) MXene-Te microplate van der Waals heterostructure based tran spare nt near-i nfrared photodetector(PD)is exploited.
基金supported by the National Research Foundation of Korea(No.NRF-2015R1A3A2066337)
文摘Graphene with an exceptional combination of electronic, optical and outstanding mechanical features has been proved to lead a completely different kind of 2-D electronics. The most exciting feature of graphene is its ultra-thin thickness, that can be conformally contacted to any kind of rough surface without losing much of its transparency and conductivity. Graphene has been explored demonstrating various prototype flexible electronic applications, however, its potentiality has been proven wherever transparent conductive electrodes（TCEs） are needed in a flexible, stretchable format. Graphene-based TCEs in flexible electronic applications showed greatly superior performance over their conventionally available competitor indium tin oxide（ITO）. Moreover, enormous applications have been emerging, especially in wearable devices that can be potentially used in our daily life as well as in biomedical areas. However, the production of high-quality, defect-free large area graphene is still a challenge and the main hurdle in the commercialization of flexible and wearable products. The objective of the present review paper is to summarize the progress made so far in graphene-based flexible and wearable applications. The current developments including challenges and future perspectives arc also highlighted.
基金This work was supported by the Ministry of Science&ICT(MSIT)and the Ministry of Trade,Industry and Energy(MOTIE)of Korea through the National Research Foundation(2019R1A2B5B03069358,2016R1A5A1009926)the Bio&Medical Technology Development Program(2018M3A9F1021649),the Nano Material Technology Development Program(2015M3A7B4050308 and 2016M3A7B4910635)the Industrial Technology Innovation Program(10080577).Also,the authors thank financial support by the Institute for Basic Science(IBS-R026-D1)and the Research Program(2018-22-0194)funded by Yonsei University.All in-vivo studies were conducted according to the guidelines of the National Institutes of Health for care and use of laboratory animals and with the approval of the Institute of Animal Care and Use Committee of UNIST(UNISTIACUC-16-19).
文摘Light-mediated therapeutics have attracted considerable attention as a method for the treatment of ophthalmologic diseases,such as age-related macular degeneration,because of their non-invasiveness and the effectiveness to ameliorate the oxidative stress of retinal cells.However,the current phototherapeutic devices are opaque,bulky,and tethered forms,so they are not feasible for use in continuous treatment during the patient’s daily life.Herein,we report wireless,wearable phototherapeutic devices with red light-emitting diodes for continuous treatments.Red light-emitting diodes were formed to be conformal to three-dimensional surfaces of glasses and contact lenses.Furthermore,fabricated light-emitting diodes had either transparency or a miniaturized size so that the user’s view is not obstructed.Also,these devices were operated wirelessly with control of the light intensity.In addition,in-vitro and in-vivo tests using human retinal epithelial cells and a live rabbit demonstrated the effectiveness and reliable operation as phototherapeutic devices.
基金supported by National Natural Science Foundation of China(12061141001).
文摘Background Gas Electron Multiplier(GEM)detectors are widely used for high-energy physics experiments,such as the triple-GEM detector installed in CMS,due to their excellent performance.A quadruple-GEM detector is regarded as the candidate for the upgrade projects of the High Luminosity LHC(HL-LHC).Method In this paper,key performance characteristics of quadruple-GEM detectors are studied in detail based on Monte Carlo simulation using the Garfield++and ANSYS software packages.The parameterization method is adopted.Result The spatial and time resolution,effective gain,efficiency,and electron transparency are obtained via simulation for different detector geometries and operating conditions.We create a quadruple-GEM structure that meets the geometric requirements of the CMS endcap muon detectors.Conclusion These studies help to understand the physical mechanisms of GEM detectors and provide references for the detector design,operating condition optimization and technical scheme selection in future applications.
