Increasing demand for timely and accurate environmental pollution monitoring and control requires new sensing techniques with outstanding performance, i.e.,high sensitivity, high selectivity, and reliability. Metal–o...Increasing demand for timely and accurate environmental pollution monitoring and control requires new sensing techniques with outstanding performance, i.e.,high sensitivity, high selectivity, and reliability. Metal–organic frameworks(MOFs), also known as porous coordination polymers, are a fascinating class of highly ordered crystalline coordination polymers formed by the coordination of metal ions/clusters and organic bridging linkers/ligands. Owing to their unique structures and properties,i.e., high surface area, tailorable pore size, high density of active sites, and high catalytic activity, various MOF-based sensing platforms have been reported for environmental contaminant detection including anions, heavy metal ions,organic compounds, and gases. In this review, recent progress in MOF-based environmental sensors is introduced with a focus on optical, electrochemical, and field-effect transistor sensors. The sensors have shown unique and promising performance in water and gas contaminant sensing. Moreover, by incorporation with other functional materials, MOF-based composites can greatly improve the sensor performance. The current limitations and future directions of MOF-based sensors are also discussed.展开更多
Two-dimensional(2D) materials have attracted extensive interest due to their excellent electrical, thermal,mechanical, and optical properties. Graphene has been one of the most explored 2D materials. However, its zero...Two-dimensional(2D) materials have attracted extensive interest due to their excellent electrical, thermal,mechanical, and optical properties. Graphene has been one of the most explored 2D materials. However, its zero band gap has limited its applications in electronic devices. Transition metal dichalcogenide(TMDC), another kind of 2D material,has a nonzero direct band gap(same charge carrier momentum in valence and conduction band) at monolayer state,promising for the efficient switching devices(e.g., field-effect transistors). This review mainly focuses on the recent advances in charge carrier mobility and the challenges to achieve high mobility in the electronic devices based on 2DTMDC materials and also includes an introduction of 2D materials along with the synthesis techniques. Finally, this review describes the possible methodology and future prospective to enhance the charge carrier mobility for electronic devices.展开更多
Neuromorphic computing is a brain-inspired computing paradigm that aims to construct efficient,low-power,and adaptive computing systems by emulating the information processing mechanisms of biological neural systems.A...Neuromorphic computing is a brain-inspired computing paradigm that aims to construct efficient,low-power,and adaptive computing systems by emulating the information processing mechanisms of biological neural systems.At the core of neuromorphic computing are neuromorphic devices that mimic the functions and dynamics of neurons and synapses,enabling the hardware implementation of artificial neural networks.Various types of neuromorphic devices have been proposed based on different physical mechanisms such as resistive switching devices and electric-double-layer transistors.These devices have demonstrated a range of neuromorphic functions such as multistate storage,spike-timing-dependent plasticity,dynamic filtering,etc.To achieve high performance neuromorphic computing systems,it is essential to fabricate neuromorphic devices compatible with the complementary metal oxide semiconductor(CMOS)manufacturing process.This improves the device’s reliability and stability and is favorable for achieving neuromorphic chips with higher integration density and low power consumption.This review summarizes CMOS-compatible neuromorphic devices and discusses their emulation of synaptic and neuronal functions as well as their applications in neuromorphic perception and computing.We highlight challenges and opportunities for further development of CMOS-compatible neuromorphic devices and systems.展开更多
Precise and continuous monitoring of biochemicals by biosensors assists to understand physiological functions for various diagnostics and therapeutic applications.For implanted biosensors,small size and flexibility ar...Precise and continuous monitoring of biochemicals by biosensors assists to understand physiological functions for various diagnostics and therapeutic applications.For implanted biosensors,small size and flexibility are essential for minimizing tissue damage and achieving accurate detection.However,the active surface area of sensor decreases as the sensor becomes smaller,which will increase the impedance and decrease the signal to noise ratio,resulting in a poor detection limit.Taking advantages of local amplification effect,organic electrochemical transistors(OECTs)constitute promising candidates for high-sensitive monitoring.However,their detections in deep tissues are rarely reported.Herein,we report a family of implantable,fiber-shaped all-in-one OECTs based on carbon nanotube fibers for versatile biochemical detection including H2O2,glucose,dopamine and glutamate.These fiber-shaped OECTs demonstrated high sensitivity,dynamical stability in physiological environment and antiinterference capability.After implantation in mouse brain,7-day dopamine monitoring in vivo was realized for the first time.These fiber-shaped OECTs could be great additions to the"life science"tool box and represent promising avenue for biomedical monitoring.展开更多
We conduct a theoretical study of the damage susceptibility trend of a typical bipolar transistor induced by a high-power microwave (HPM) as a function of frequency. The dependences of the burnout time and the damag...We conduct a theoretical study of the damage susceptibility trend of a typical bipolar transistor induced by a high-power microwave (HPM) as a function of frequency. The dependences of the burnout time and the damage power on the signal frequency are obtained. Studies of the internal damage process and the mechanism of the device are carried out from the variation analysis of the distribution of the electric field, current density, and temperature. The investigation shows that the burnout time linearly depends on the signal frequency. The current density and the electric field at the damage position decrease with increasing frequency. Meanwhile, the temperature elevation occurs in the area between the p-n junction and the n n+ interface due to the increase of the electric field. Adopting the data analysis software, the relationship between the damage power and frequency is obtained. Moreover, the thickness of the substrate has a significant effect on the burnout time.展开更多
Van der Waals(vdW)heterostructures provide a unique opportunity to develop various electronic and optoelectronic devices with specific functions by designing novel device structures,especially for bioinspired neuromor...Van der Waals(vdW)heterostructures provide a unique opportunity to develop various electronic and optoelectronic devices with specific functions by designing novel device structures,especially for bioinspired neuromorphic optoelectronic devices,which require the integration of nonvolatile memory and excellent optical responses.Here,we demonstrate a programmable optoelectronic synaptic floating-gate transistor based on multilayer graphene/h-BN/MoS2 vdW heterostructures,where both plasticity emulation and modulation were successfully realized in a single device.The dynamic tunneling process of photogenerated carriers through the as-fabricated vdW heterostructures contributed to a large memory ratio(105)between program and erase states.Our device can work as a functional or silent synapse by applying a program/erase voltage spike as a modulatory signal to determine the response to light stimulation,leading to a programmable operation in optoelectronic synaptic transistors.Moreover,an ultra-low energy consumption per light spike event(~2.5 fJ)was obtained in the program state owing to a suppressed noise current by program operation in our floating-gate transistor.This study proposes a feasible strategy to improve the functions of optoelectronic synaptic devices with ultra-low energy consumption based on vdW heterostructures designed for highly efficient artificial neural networks.展开更多
Organic field-effect transistors(OFETs) are attracting more and more attention due to their potential applications in low-cost, large-area and flexible electronic products. Organic semiconductors(OSCs) are the key com...Organic field-effect transistors(OFETs) are attracting more and more attention due to their potential applications in low-cost, large-area and flexible electronic products. Organic semiconductors(OSCs) are the key components of OFETs and basically determine the device performance. The past five years have witnessed great progress of OSCs. OSCs used for OFETs have made rapid progress, with field-effect mobility much larger than that of amorphous silicon(0.5?1.0 cm2/(V s)) and of up to 10 cm2/(V s) or even higher. In this review, we demonstrate the latest progress of OSCs for OFETs, where more than 50 representative OSCs are highlighted and analyzed to give some valuable insights for this important but challenging field.展开更多
Effective thermal control systems are essential for the reliable working of insulated gate bipolar transistors (IGBTs) in many applications. A novel spray cooling loop system with integrated sintered porous copper w...Effective thermal control systems are essential for the reliable working of insulated gate bipolar transistors (IGBTs) in many applications. A novel spray cooling loop system with integrated sintered porous copper wick (SCLS-SPC) is proposed to meet the requirements of higher device level heat fluxes and the harsh environments in some applications such as hybrid, fuel cell vehicles and aerospace. Fuzzy logic and proportional-integral-derivative (PID) policies are applied to adjust the electronic temperature within a safe working range. To evaluate the thermal control effect, a mathematical model of a 4-node thermal network and pump are established for predicting the dynamics of the SCLS-SPC. Moreover, the transient response of the 4 nodes and vapor mass flowrate under no control, PID and Fuzzy-PID are numerically investigated and discussed in detail.展开更多
The evaluation of thermal resistance constitution for packaged A1GaN/GaN high electron mobility transistor (HEMT) by structure function method is proposed in this paper. The evaluation is based on the transient heat...The evaluation of thermal resistance constitution for packaged A1GaN/GaN high electron mobility transistor (HEMT) by structure function method is proposed in this paper. The evaluation is based on the transient heating measurement of the A1GaN/GaN HEMT by pulsed electrical temperature sensitive parameter method. The extracted chip-level and package-level thermal resistances of the packaged multi-finger A1GaN/GaN HEMT with 400μm SiC substrate are 22.5 K/W and 7.2 K/W respectively, which provides a non-invasive method to evaluate the chip-level thermal resistance of packaged A1GaN/GaN HEMTs. It is also experimentally proved that the extraction of the chip- level thermal resistance by this proposed method is not influenced by package form of the tested device and temperature boundary condition of measurement stage.展开更多
基金supported by the National Natural Science Foundation of China (No.21707102)1000 Talents Plan of China
文摘Increasing demand for timely and accurate environmental pollution monitoring and control requires new sensing techniques with outstanding performance, i.e.,high sensitivity, high selectivity, and reliability. Metal–organic frameworks(MOFs), also known as porous coordination polymers, are a fascinating class of highly ordered crystalline coordination polymers formed by the coordination of metal ions/clusters and organic bridging linkers/ligands. Owing to their unique structures and properties,i.e., high surface area, tailorable pore size, high density of active sites, and high catalytic activity, various MOF-based sensing platforms have been reported for environmental contaminant detection including anions, heavy metal ions,organic compounds, and gases. In this review, recent progress in MOF-based environmental sensors is introduced with a focus on optical, electrochemical, and field-effect transistor sensors. The sensors have shown unique and promising performance in water and gas contaminant sensing. Moreover, by incorporation with other functional materials, MOF-based composites can greatly improve the sensor performance. The current limitations and future directions of MOF-based sensors are also discussed.
基金funded by Australian Research Council discovery project DP140103041Future Fellowship FT160100205
文摘Two-dimensional(2D) materials have attracted extensive interest due to their excellent electrical, thermal,mechanical, and optical properties. Graphene has been one of the most explored 2D materials. However, its zero band gap has limited its applications in electronic devices. Transition metal dichalcogenide(TMDC), another kind of 2D material,has a nonzero direct band gap(same charge carrier momentum in valence and conduction band) at monolayer state,promising for the efficient switching devices(e.g., field-effect transistors). This review mainly focuses on the recent advances in charge carrier mobility and the challenges to achieve high mobility in the electronic devices based on 2DTMDC materials and also includes an introduction of 2D materials along with the synthesis techniques. Finally, this review describes the possible methodology and future prospective to enhance the charge carrier mobility for electronic devices.
基金supported by the National Natural Science Foundation of China(Grant Nos.62074075,62174082,and 61834001).
文摘Neuromorphic computing is a brain-inspired computing paradigm that aims to construct efficient,low-power,and adaptive computing systems by emulating the information processing mechanisms of biological neural systems.At the core of neuromorphic computing are neuromorphic devices that mimic the functions and dynamics of neurons and synapses,enabling the hardware implementation of artificial neural networks.Various types of neuromorphic devices have been proposed based on different physical mechanisms such as resistive switching devices and electric-double-layer transistors.These devices have demonstrated a range of neuromorphic functions such as multistate storage,spike-timing-dependent plasticity,dynamic filtering,etc.To achieve high performance neuromorphic computing systems,it is essential to fabricate neuromorphic devices compatible with the complementary metal oxide semiconductor(CMOS)manufacturing process.This improves the device’s reliability and stability and is favorable for achieving neuromorphic chips with higher integration density and low power consumption.This review summarizes CMOS-compatible neuromorphic devices and discusses their emulation of synaptic and neuronal functions as well as their applications in neuromorphic perception and computing.We highlight challenges and opportunities for further development of CMOS-compatible neuromorphic devices and systems.
基金the National Natural Science Foundation of China(2163400351673043)+3 种基金Ministry of Science and Technology of China(2016YFA0203302)Science and Technology Commission of Shanghai Municipality(17QA1400400)Shanghai Municipal Education Commission(2017-01-07-00-07-E00062)Yanchang Petroleum Group。
文摘Precise and continuous monitoring of biochemicals by biosensors assists to understand physiological functions for various diagnostics and therapeutic applications.For implanted biosensors,small size and flexibility are essential for minimizing tissue damage and achieving accurate detection.However,the active surface area of sensor decreases as the sensor becomes smaller,which will increase the impedance and decrease the signal to noise ratio,resulting in a poor detection limit.Taking advantages of local amplification effect,organic electrochemical transistors(OECTs)constitute promising candidates for high-sensitive monitoring.However,their detections in deep tissues are rarely reported.Herein,we report a family of implantable,fiber-shaped all-in-one OECTs based on carbon nanotube fibers for versatile biochemical detection including H2O2,glucose,dopamine and glutamate.These fiber-shaped OECTs demonstrated high sensitivity,dynamical stability in physiological environment and antiinterference capability.After implantation in mouse brain,7-day dopamine monitoring in vivo was realized for the first time.These fiber-shaped OECTs could be great additions to the"life science"tool box and represent promising avenue for biomedical monitoring.
基金Project supported by the National Natural Science Foundation of China (Grant No. 60776034)
文摘We conduct a theoretical study of the damage susceptibility trend of a typical bipolar transistor induced by a high-power microwave (HPM) as a function of frequency. The dependences of the burnout time and the damage power on the signal frequency are obtained. Studies of the internal damage process and the mechanism of the device are carried out from the variation analysis of the distribution of the electric field, current density, and temperature. The investigation shows that the burnout time linearly depends on the signal frequency. The current density and the electric field at the damage position decrease with increasing frequency. Meanwhile, the temperature elevation occurs in the area between the p-n junction and the n n+ interface due to the increase of the electric field. Adopting the data analysis software, the relationship between the damage power and frequency is obtained. Moreover, the thickness of the substrate has a significant effect on the burnout time.
基金National Natural Science Foundation of China,Grant/Award Numbers:62104017,52072204,62074015National Postdoctoral Program for Innovative Talents of China,Grant/Award Number:BX20200049China Postdoctoral Science Foundation,Grant/Award Number:2021M690013。
文摘Van der Waals(vdW)heterostructures provide a unique opportunity to develop various electronic and optoelectronic devices with specific functions by designing novel device structures,especially for bioinspired neuromorphic optoelectronic devices,which require the integration of nonvolatile memory and excellent optical responses.Here,we demonstrate a programmable optoelectronic synaptic floating-gate transistor based on multilayer graphene/h-BN/MoS2 vdW heterostructures,where both plasticity emulation and modulation were successfully realized in a single device.The dynamic tunneling process of photogenerated carriers through the as-fabricated vdW heterostructures contributed to a large memory ratio(105)between program and erase states.Our device can work as a functional or silent synapse by applying a program/erase voltage spike as a modulatory signal to determine the response to light stimulation,leading to a programmable operation in optoelectronic synaptic transistors.Moreover,an ultra-low energy consumption per light spike event(~2.5 fJ)was obtained in the program state owing to a suppressed noise current by program operation in our floating-gate transistor.This study proposes a feasible strategy to improve the functions of optoelectronic synaptic devices with ultra-low energy consumption based on vdW heterostructures designed for highly efficient artificial neural networks.
基金supported by the"Strategic Priority Research Program"(XDB12010100)the National Natural Science Foundation of China(20902105,51173200)+1 种基金the National Basic Research Program of China(2011CB932300)Merck Chemicals Ltd,and the Chinese Academy of Sciences
文摘Organic field-effect transistors(OFETs) are attracting more and more attention due to their potential applications in low-cost, large-area and flexible electronic products. Organic semiconductors(OSCs) are the key components of OFETs and basically determine the device performance. The past five years have witnessed great progress of OSCs. OSCs used for OFETs have made rapid progress, with field-effect mobility much larger than that of amorphous silicon(0.5?1.0 cm2/(V s)) and of up to 10 cm2/(V s) or even higher. In this review, we demonstrate the latest progress of OSCs for OFETs, where more than 50 representative OSCs are highlighted and analyzed to give some valuable insights for this important but challenging field.
文摘Effective thermal control systems are essential for the reliable working of insulated gate bipolar transistors (IGBTs) in many applications. A novel spray cooling loop system with integrated sintered porous copper wick (SCLS-SPC) is proposed to meet the requirements of higher device level heat fluxes and the harsh environments in some applications such as hybrid, fuel cell vehicles and aerospace. Fuzzy logic and proportional-integral-derivative (PID) policies are applied to adjust the electronic temperature within a safe working range. To evaluate the thermal control effect, a mathematical model of a 4-node thermal network and pump are established for predicting the dynamics of the SCLS-SPC. Moreover, the transient response of the 4 nodes and vapor mass flowrate under no control, PID and Fuzzy-PID are numerically investigated and discussed in detail.
基金supported by the Natural Science Foundation of Beijing,China (Grant No. 4092005)the National High Technology Research and Development Program of China (Grant No. 2009AA032704)the Specialized Research Fund for the Doctoral Program of Higher Education of China (Grant No. 20091103110006)
文摘The evaluation of thermal resistance constitution for packaged A1GaN/GaN high electron mobility transistor (HEMT) by structure function method is proposed in this paper. The evaluation is based on the transient heating measurement of the A1GaN/GaN HEMT by pulsed electrical temperature sensitive parameter method. The extracted chip-level and package-level thermal resistances of the packaged multi-finger A1GaN/GaN HEMT with 400μm SiC substrate are 22.5 K/W and 7.2 K/W respectively, which provides a non-invasive method to evaluate the chip-level thermal resistance of packaged A1GaN/GaN HEMTs. It is also experimentally proved that the extraction of the chip- level thermal resistance by this proposed method is not influenced by package form of the tested device and temperature boundary condition of measurement stage.