The synergistic effect of total ionizing dose(TID) and single event gate rupture(SEGR) in SiC power metal–oxide–semiconductor field effect transistors(MOSFETs) is investigated via simulation. The device is found to ...The synergistic effect of total ionizing dose(TID) and single event gate rupture(SEGR) in SiC power metal–oxide–semiconductor field effect transistors(MOSFETs) is investigated via simulation. The device is found to be more sensitive to SEGR with TID increasing, especially at higher temperature. The microscopic mechanism is revealed to be the increased trapped charges induced by TID and subsequent enhancement of electric field intensity inside the oxide layer.展开更多
This paper briefly introduces the five types of the surgical operations in knot theory and obtains the expression of single qubit quantum logic gate in terms of these surgical operations.
A nuclear cardiology test is the most commonly performed non-invasive cardiac imaging test in patients with heart failure, and it plays a pivotal role in their assessment and management. Quantitative gated single posi...A nuclear cardiology test is the most commonly performed non-invasive cardiac imaging test in patients with heart failure, and it plays a pivotal role in their assessment and management. Quantitative gated single positron emission computed tomography (QGS) is used to assess quantitatively cardiac volume, left ventricular ejection fraction (LVEF), stroke volume, and cardiac diastolic function. Resting and stress myocardial perfusion imaging, with exercise or pharmacologic stress, plays a fundamental role in distinguishing ischemic from nonischemic etiology of heart failure, and in demonstrating myocardial viability. Diastolic heart failure also termed as heart failure with a preserved LVEF is readily identified by nuclear cardiology techniques and can accurately be estimated by peak filling rate (PFR) and time to PFR. Movement of the left ventricle can also be readily assessed by QGS, with newer techniques such as threedimensional, wall thickening evaluation aiding its assessment. Myocardial perfusion imaging is also commonly used to identify candidates for implantable cardiac defibrillator and cardiac resynchronization therapies. Neurotransmitter imaging using 123 I-metaiodobenzylguanidine offers prognostic information in patients with heart failure. Metabolism and function in the heart are closely related, and energy substrate metabolism is a potential target of medical therapies to improve cardiac function in patients with heart failure. Cardiac metabolic imaging using 123 I-15-(p-iodophenyl)3-R, S-methylpentadecacoic acid is a commonly used tracer in clinical studies to diagnose metabolic heart failure. Nuclear cardiology tests, including neurotransmitter imaging and metabolic imaging, are now easily preformed with new tracers to refine heart failure diagnosis. Nuclear cardiology studies contribute significantly to guiding management decisions for identifying cardiac risk in patients with heart failure.展开更多
An analytical surface potential model for the single material double work function gate （SMDWG） MOSFET is developed based on the exact resultant solution of the two-dimensional Poisson equation. The model includes t...An analytical surface potential model for the single material double work function gate （SMDWG） MOSFET is developed based on the exact resultant solution of the two-dimensional Poisson equation. The model includes the effects of drain biases, gate oxide thickness, different combinations of S-gate and D-gate length and values of substrate doping concentration. More attention has been paid to seeking to explain the attributes of the SMDWG MOSFET, such as suppressing drain-induced barrier lowering （DIBL）, accelerating carrier drift velocity and device speed. The model is verified by comparison to the simulated results using the device simulator MEDICI. The accuracy of the results obtained using our analytical model is verified using numerical simulations. The model not only offers the physical insight into device physics but also provides the basic designing guideline for the device.展开更多
A single gate Ⅲ-Ⅴ junctionless tunnel field effect transistor（SG-JLTFET） has been reported which shows excellent dc characteristics at low power supply operation.This device has a thin uniformly n-type doped chann...A single gate Ⅲ-Ⅴ junctionless tunnel field effect transistor（SG-JLTFET） has been reported which shows excellent dc characteristics at low power supply operation.This device has a thin uniformly n-type doped channel of GaSb i.e.gallium antimonide which is grown epitaxially over silicon substrate.The DC performance parameters such as I（on）,I（on）/I（off）,average and point subthreshold slope as well as device parameters for analog applications viz.transconductance gm,transconductance generation efficiency gm/ID,various capacitances and the unity gain frequency fT are studied using a device simulator.Along with examining its endurance to short channel effects,the performances are also compared with a Silicon Dual Gate Junctionless Tunnel FET（DG-JLTFET）.The DC and small signal analog performance reflects that GaSb SG-JLTFET has immense purview for extreme high-frequency and low-power applications.展开更多
Vehicle detection in dim light has always been a challenging task.In addition to the unavoidable noise,the uneven spatial distribution of light and dark due to vehicle lights and street lamps can further make the prob...Vehicle detection in dim light has always been a challenging task.In addition to the unavoidable noise,the uneven spatial distribution of light and dark due to vehicle lights and street lamps can further make the problem more difficult.Conventional image enhancement methods may produce over smoothing or over exposure problems,causing irreversible information loss to the vehicle targets to be subsequently detected.Therefore,we propose a multi-exposure generation and fusion network.In the multi-exposure generation network,we employ a single gated convolutional recurrent network with two-stream progressive exposure input to generate intermediate images with gradually increasing exposure,which are provided to the multi-exposure fusion network after a spatial attention mechanism.Then,a pre-trained vehicle detection model in normal light is used as the basis of the fusion network,and the two models are connected using the convolutional kernel channel dimension expansion technique.This allows the fusion module to provide vehicle detection information,which can be used to guide the generation network tofine-tune the parameters and thus complete end-to-end enhancement and training.By coupling the two parts,we can achieve detail interaction and feature fusion under different lighting conditions.Our experimental results demonstrate that our proposed method is better than the state-of-the-art detection methods after image luminance enhancement on the ODDS dataset.展开更多
Single event irradiation-hardened power MOSFET is the most important device for DC/DC converter in space environment application. Single event gate rupture （SEGR） and single event burnout （SEB）, which will degrade...Single event irradiation-hardened power MOSFET is the most important device for DC/DC converter in space environment application. Single event gate rupture （SEGR） and single event burnout （SEB）, which will degrade the running safety and reliability of spacecraft, are the two typical failure modes in power MOSFETs. In this paper, based on recombination mechanism of interface between oxide and silicon, a novel hardened power MOS- FETs structure for SEGR and SEB is proposed. The structure comprises double stagger partial silicon-on-insulator （DSPSOI） layers. Results show that the safety operation area （SOA） of a 130 V N-channel power MOSFET in single event irradiation environment is enhanced by up to 50% when the linear-energy-transfer value of heavy ion is a constant of 98 MeV-cm2/mg in the whole incident track, and the other parameters are almost maintained at the same value. Thus this novel structure can be widely used in designing single event irradiation-hardened power MOSFETs.展开更多
Broken-gap(type-Ⅲ)two-dimensional(2D)van der Waals heterostructures(vdWHs)offer an ideal platform for interband tunneling devices due to their broken-gap band offset and sharp band edge.Here,we demonstrate an efficie...Broken-gap(type-Ⅲ)two-dimensional(2D)van der Waals heterostructures(vdWHs)offer an ideal platform for interband tunneling devices due to their broken-gap band offset and sharp band edge.Here,we demonstrate an efficient control of energy band alignment in a typical type-ⅢvdWH,which is composed of vertically-stacked molybdenum telluride(MoTe2)and tin diselenide(SnSe2),via both electrostatic and optical modulation.By a single electrostatic gating with hexagonal boron nitride(hBN)as the dielectric,a variety of electrical transport characteristics including forward rectifying,Zener tunneling,and backward rectifying are realized on the same heterojunction at low gate voltages of±1 V.In particular,the heterostructure can function as an Esaki tunnel diode with a room-temperature negative differential resistance.This great tunability originates from the atomicallyflat and inert surface of h-BN that significantly suppresses the interfacial trap scattering and strain effects.Upon the illumination of an 885 nm laser,the band alignment of heterojunction can be further tuned to facilitate the direct tunneling of photogenerated charge carriers,which leads to a high photocurrent on/off ratio of>105 and a competitive photodetectivity of 1.03×1012 Jones at zero bias.Moreover,the open-circuit voltage of irradiated heterojunction can be switched from positive to negative at opposite gate voltages,revealing a transition from accumulation mode to depletion mode.Our findings not only promise a simple strategy to tailor the bands of type-ⅢvdWHs but also provide an in-depth understanding of interlayer tunneling for future low-power electronic and optoelectronic applications.展开更多
Single event gate rupture（SEGR） is a very important failure mode for power MOSFETs when used in aerospace applications,and the cell regions are widely considered to be the most sensitive to SEGR.However, experimenta...Single event gate rupture（SEGR） is a very important failure mode for power MOSFETs when used in aerospace applications,and the cell regions are widely considered to be the most sensitive to SEGR.However, experimental results show that SEGR can also happen in the gate bus regions.In this paper,we used simulation tools to estimate three structures in power MOSFETs,and found that if certain conditions are met,areas other than cell regions can become sensitive to SEGR.Finally,some proposals are given as to how to reduce SEGR in different regions.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant No.12004329)Open Project of State Key Laboratory of Intense Pulsed Radiation Simulation and Effect(Grant No.SKLIPR2115)+1 种基金Postgraduate Research and Practice Innovation Program of Jiangsu Province(Grant No.SJCX22_1704)Innovative Science and Technology Platform Project of Cooperation between Yangzhou City and Yangzhou University,China(Grant Nos.YZ202026301 and YZ202026306)。
文摘The synergistic effect of total ionizing dose(TID) and single event gate rupture(SEGR) in SiC power metal–oxide–semiconductor field effect transistors(MOSFETs) is investigated via simulation. The device is found to be more sensitive to SEGR with TID increasing, especially at higher temperature. The microscopic mechanism is revealed to be the increased trapped charges induced by TID and subsequent enhancement of electric field intensity inside the oxide layer.
文摘This paper briefly introduces the five types of the surgical operations in knot theory and obtains the expression of single qubit quantum logic gate in terms of these surgical operations.
文摘A nuclear cardiology test is the most commonly performed non-invasive cardiac imaging test in patients with heart failure, and it plays a pivotal role in their assessment and management. Quantitative gated single positron emission computed tomography (QGS) is used to assess quantitatively cardiac volume, left ventricular ejection fraction (LVEF), stroke volume, and cardiac diastolic function. Resting and stress myocardial perfusion imaging, with exercise or pharmacologic stress, plays a fundamental role in distinguishing ischemic from nonischemic etiology of heart failure, and in demonstrating myocardial viability. Diastolic heart failure also termed as heart failure with a preserved LVEF is readily identified by nuclear cardiology techniques and can accurately be estimated by peak filling rate (PFR) and time to PFR. Movement of the left ventricle can also be readily assessed by QGS, with newer techniques such as threedimensional, wall thickening evaluation aiding its assessment. Myocardial perfusion imaging is also commonly used to identify candidates for implantable cardiac defibrillator and cardiac resynchronization therapies. Neurotransmitter imaging using 123 I-metaiodobenzylguanidine offers prognostic information in patients with heart failure. Metabolism and function in the heart are closely related, and energy substrate metabolism is a potential target of medical therapies to improve cardiac function in patients with heart failure. Cardiac metabolic imaging using 123 I-15-(p-iodophenyl)3-R, S-methylpentadecacoic acid is a commonly used tracer in clinical studies to diagnose metabolic heart failure. Nuclear cardiology tests, including neurotransmitter imaging and metabolic imaging, are now easily preformed with new tracers to refine heart failure diagnosis. Nuclear cardiology studies contribute significantly to guiding management decisions for identifying cardiac risk in patients with heart failure.
基金supported by the National Youth Science Foundation of China(No.61006064)the Natural Science Foundation of Education Office,Anhui Province(No.KJ2013A071)
文摘An analytical surface potential model for the single material double work function gate （SMDWG） MOSFET is developed based on the exact resultant solution of the two-dimensional Poisson equation. The model includes the effects of drain biases, gate oxide thickness, different combinations of S-gate and D-gate length and values of substrate doping concentration. More attention has been paid to seeking to explain the attributes of the SMDWG MOSFET, such as suppressing drain-induced barrier lowering （DIBL）, accelerating carrier drift velocity and device speed. The model is verified by comparison to the simulated results using the device simulator MEDICI. The accuracy of the results obtained using our analytical model is verified using numerical simulations. The model not only offers the physical insight into device physics but also provides the basic designing guideline for the device.
文摘A single gate Ⅲ-Ⅴ junctionless tunnel field effect transistor（SG-JLTFET） has been reported which shows excellent dc characteristics at low power supply operation.This device has a thin uniformly n-type doped channel of GaSb i.e.gallium antimonide which is grown epitaxially over silicon substrate.The DC performance parameters such as I（on）,I（on）/I（off）,average and point subthreshold slope as well as device parameters for analog applications viz.transconductance gm,transconductance generation efficiency gm/ID,various capacitances and the unity gain frequency fT are studied using a device simulator.Along with examining its endurance to short channel effects,the performances are also compared with a Silicon Dual Gate Junctionless Tunnel FET（DG-JLTFET）.The DC and small signal analog performance reflects that GaSb SG-JLTFET has immense purview for extreme high-frequency and low-power applications.
基金supported in part by the Science and Technology Innovation foundation(No.JSGG20210802152811033).
文摘Vehicle detection in dim light has always been a challenging task.In addition to the unavoidable noise,the uneven spatial distribution of light and dark due to vehicle lights and street lamps can further make the problem more difficult.Conventional image enhancement methods may produce over smoothing or over exposure problems,causing irreversible information loss to the vehicle targets to be subsequently detected.Therefore,we propose a multi-exposure generation and fusion network.In the multi-exposure generation network,we employ a single gated convolutional recurrent network with two-stream progressive exposure input to generate intermediate images with gradually increasing exposure,which are provided to the multi-exposure fusion network after a spatial attention mechanism.Then,a pre-trained vehicle detection model in normal light is used as the basis of the fusion network,and the two models are connected using the convolutional kernel channel dimension expansion technique.This allows the fusion module to provide vehicle detection information,which can be used to guide the generation network tofine-tune the parameters and thus complete end-to-end enhancement and training.By coupling the two parts,we can achieve detail interaction and feature fusion under different lighting conditions.Our experimental results demonstrate that our proposed method is better than the state-of-the-art detection methods after image luminance enhancement on the ODDS dataset.
基金Project supported by the National Natural Science Foundation of China(No.61464002)the Grand Science and Technology Special Project in Guizhou Province of China(No.[2015]6006)the Ministry of Education Open Foundation for Semiconductor Power Device Reliability(No.010201)
文摘Single event irradiation-hardened power MOSFET is the most important device for DC/DC converter in space environment application. Single event gate rupture （SEGR） and single event burnout （SEB）, which will degrade the running safety and reliability of spacecraft, are the two typical failure modes in power MOSFETs. In this paper, based on recombination mechanism of interface between oxide and silicon, a novel hardened power MOS- FETs structure for SEGR and SEB is proposed. The structure comprises double stagger partial silicon-on-insulator （DSPSOI） layers. Results show that the safety operation area （SOA） of a 130 V N-channel power MOSFET in single event irradiation environment is enhanced by up to 50% when the linear-energy-transfer value of heavy ion is a constant of 98 MeV-cm2/mg in the whole incident track, and the other parameters are almost maintained at the same value. Thus this novel structure can be widely used in designing single event irradiation-hardened power MOSFETs.
基金the National Natural Science Foundation of China(No.62004128)Fundamental Research Foundation of Shenzhen(No.JCYJ20190808152607389)the technical support from the Photonics Center of Shenzhen University.
文摘Broken-gap(type-Ⅲ)two-dimensional(2D)van der Waals heterostructures(vdWHs)offer an ideal platform for interband tunneling devices due to their broken-gap band offset and sharp band edge.Here,we demonstrate an efficient control of energy band alignment in a typical type-ⅢvdWH,which is composed of vertically-stacked molybdenum telluride(MoTe2)and tin diselenide(SnSe2),via both electrostatic and optical modulation.By a single electrostatic gating with hexagonal boron nitride(hBN)as the dielectric,a variety of electrical transport characteristics including forward rectifying,Zener tunneling,and backward rectifying are realized on the same heterojunction at low gate voltages of±1 V.In particular,the heterostructure can function as an Esaki tunnel diode with a room-temperature negative differential resistance.This great tunability originates from the atomicallyflat and inert surface of h-BN that significantly suppresses the interfacial trap scattering and strain effects.Upon the illumination of an 885 nm laser,the band alignment of heterojunction can be further tuned to facilitate the direct tunneling of photogenerated charge carriers,which leads to a high photocurrent on/off ratio of>105 and a competitive photodetectivity of 1.03×1012 Jones at zero bias.Moreover,the open-circuit voltage of irradiated heterojunction can be switched from positive to negative at opposite gate voltages,revealing a transition from accumulation mode to depletion mode.Our findings not only promise a simple strategy to tailor the bands of type-ⅢvdWHs but also provide an in-depth understanding of interlayer tunneling for future low-power electronic and optoelectronic applications.
文摘Single event gate rupture（SEGR） is a very important failure mode for power MOSFETs when used in aerospace applications,and the cell regions are widely considered to be the most sensitive to SEGR.However, experimental results show that SEGR can also happen in the gate bus regions.In this paper,we used simulation tools to estimate three structures in power MOSFETs,and found that if certain conditions are met,areas other than cell regions can become sensitive to SEGR.Finally,some proposals are given as to how to reduce SEGR in different regions.
