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关键词： Cryogenics   Temperature distribution   Data models   Threshold voltage   Mathematical models   Semiconductor device modeling   Solid modeling   BSIM-BULK   compact model   cryogenics   mobility   MOSFET   transconductance  

摘要： In this work, we present a compact temperature-dependent model for bulk MOSFETs with applicability down to the cryogenic range of temperatures and validate it against the experimental data. The long-channel and low-threshold voltage MOSFET device is characterized by multiple bias conditions and temperatures. With decreasing temperature, the characteristics exhibit a positive temperature shift in threshold voltage, an increase in the low-field carrier mobility, higher mobility degradation, and subthreshold swing (SS) saturation. Furthermore, the transconductance shows a nonmonotonic behavior with respect to temperature. The observed temperature-dependent variations in the device characteristics have been thoroughly analyzed, incorporated into the temperature-dependent parameters of the BSIM-BULK model, and validated using our characterized data and experimental data from other recent publications. The accuracy of the model and physical correctness are effectively demonstrated by carrying out the Gummel symmetry test (GST), the slope ratio (SR) test, and the tree top test. This study also analyzes the behavior of the results of the SR and tree top tests at cryogenic temperature, presenting these findings for the first time.

关键词： LDMOS   High k   Variable lateral doping technique   Short-circuit capacity   Breakdown voltage  

摘要： In this article, a novel high - k and equivalent variable lateral doping 4H-SiC lateral double -diffused metal oxide semiconductor (LDMOS) field-effect transistor with improved performance is proposed and calibrated by numerical simulation. The three-dimensional equivalently P -top region is employed in the drift region, and only one additional ion implantation step is needed to achieve variable lateral doping (VLD) technique. The VLD technique combined with the high - k dielectric in the drift region, not only increases the doping concentration of N -drift region, but also optimizes the electric field distribution in the drift region. Simulation results indicates that the BV , specific on -resistance and the short-circuit withstand time of the proposed H k VLD LDMOS are improved by 48.91%, 53.6% and 60.2% respectively, compared with those of the conventional LDMOS device.

关键词： SiC MOSFET   active drive circuit   overshoot   oscillation  

摘要： Silicon carbide (SiC) MOSFETs exhibit superior performance compared to traditional silicon (Si) MOSFETs, characterized by faster switching speeds, lower on-resistance, higher breakdown voltage, and greater operational temperature tolerance. These attributes make SiC MOSFETs highly suitable for applications in electric vehicles, charging stations, and mobile devices. However, their rapid switching speed can intensify current and voltage overshoot and oscillations during device switching, leading to increased device losses or potential damage. To address this issue, this paper proposes a current-type active gate drive (AGD) circuit. The circuit first detects the rate of change in the drain current and drain-source voltage. Subsequently, it employs an analog amplifier circuit and adjustable drive resistors to decelerate the rate of change in the drain-source voltage and drain current. As a result, overshoot and oscillation in the drain-source voltage and drain current are mitigated. Experimental results demonstrate that the proposed AGD circuit can reduce drain current overshoot by 60%, drain-source voltage overshoot by 15.38%, and waveform oscillations. Additionally, the AGD circuit decreases conduction and turn-off losses by 24% and effectively mitigates electromagnetic interference (EMI) issues within the frequency range of 0.1 to 3 MHz.

关键词： carbon nanotube   field emission   cold cathode   MOSFET   electron gun  

摘要： The carbon nanotube cold cathode has important applications in the X-ray source, microwave tube, neutralizer, etc. In this study, the characteristics of carbon nanotube (CNT) electron gun in series with metal-oxide-semiconductor field-effect transistor (MOSFET) were studied. CNTs were prepared on a stainless steel substrate by chemical vapor deposition and assembled with a mesh gate to form an electron gun. The anode current of the electron gun can be accurately regulated by precisely controlling the MOSFET gate voltage in the subthreshold region from 1 to 40 mu A. The current stability measurements show the cathode current fluctuation was 0.87% under 10 h continuous operation, and the corresponding anode current fluctuation was 2.3%. The result has demonstrated that the MOSFET can be applied for the precise control of the CNT electron gun and greatly improve current stability.

关键词： MOSFET   Logic gates   Silicon carbide   Radiation effects   Ions   Periodic structures   Electric fields   2-D numerical simulation   lattice temperature   linear energy transfer (LET)   silicon-carbide (SiC) MOSFET   single-event burnout (SEB)  

摘要： A 1200-V rated CoolSiC Trench MOSFET structure has excellent overall electrical characteristics dueto its unique asymmetric structure. However, it is sensi-tive to space heavy ion radiation. In this study, heavy ionirradiation experiments were conducted on 1.2 kV Cool-SiC Trench MOSFET devices to calibrate the simulationstructure model and critical failure conditions. The 2-Dnumerical simulator SILVACO TCAD was used to inves-tigate the single event burnout (SEB) hardening methodfor the 1.2 kV-rated CoolSiC Trench MOSFET under highlinear energy transfer (LET) values. The simulation resultsshow that the improved CoolSiC Trench MOSFET structurecan effectively enhance the SEB capability of the devicewithout sacrificing its excellent overall electrical character-istics compared to the traditional CoolSiC Trench MOSFET. At 360 V voltage and 0.5 pC/mu m LET value, the highest temperature is reduced from 3097 to 1502 K, and the lowest burnout threshold is increased by 200 V in the improved structure while maintaining almost unchanged characteristics at other locations

关键词： Meminductor Emulator   MOSFET-C   Non-volatility   Pinched Hysteresis Loop   Chaotic Oscillator  

摘要： This article presents a grounded meminductor emulator architecture based on only MOSFETs and two capacitors. Proposed models do not use any extra components like a resistor, multiplier, or buffer. The simulation and verification of the proposed emulator are performed using Cadence Virtuoso with a 180 nm CMOS process parameter. The offered emulator requires +/- 0.9 V DC power supply and its static power consumption is 0.421 mW. The maximum operating frequency of the meminductor is 32 MHz. The usefulness and reliability of the offered design are tested by performing various types of simulation including Monte Carlo and temperature variation. The chaotic oscillator is designed that demonstrate the viability of the suggested meminductor emulator.

关键词： Threshold voltage  

摘要： Of late, there has been a tremendous surge in the development of field-effect transistors of various kinds because of their versatile nature of applications in the frontier fields of science and technology. Among them, metal oxide semiconducting field-effect transistors (MOSFET) offer cutting-edge technology in a cost-efficient way of fabricating the device, which focuses on enlarged active area and high area efficiency that could be achieved using simple fabrication processes. The top contact-bottom gate approach has been chosen for the fabrication of an Indium Zinc Oxide MOSFET utilizing silver (Ag) as the source and drain materials. High k-dielectric layer Al2O3 has been deposited onto the n-type phosphorus-doped silicon substrate, which functions as a gate layer. The fabrication process is entailed with the solution processing technique along with the spin coating process. Electrical characterization on the IZO MOSFET shows promising results in the field-effect mobility of 21.37 cm2 V-1 S-1, a subthreshold slope of 0.181 V/decade, and a threshold voltage of 1.2608 V, respectively. The electrical characterization was considered under different atmospheres like dark and daylight showcasing the photoresponsivity which leads to the possible potential for optoelectronic devices. Transport properties of the fabricated IZO MOSFET have been determined by Hall measurements which indicate an electron density of 0.343 x 1023 cm-3 as well as an electron mobility of 2.305 x 10-4 cm2 eV-1 S-1. The structural analyses have been investigated using X-ray diffraction and X-ray photoelectron spectroscopic techniques which could confirm the composition and the film quality of the fabricated materials on the substrate. Surface morphology and structural characterization of the thin film have been studied using SEM and AFM studies. Major applications of IZO MOSFET include power electronics such as power supplies, inverters, and motor control systems.

关键词： Memristor emulator   PGME-3/NGME-3   Mateiral implication   GHz-level  

摘要： PGME-3/NGME-3 only consists of three MOSFETs and can be operated at 5 GHz. The minimum step time of the material implication circuit based on PGME-3 and NGME-3 is 70 ps. However, the negative/positive lobe of PGME-3/NMGE-3's ii-vi\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$i_i-v_i$$\end{document} curve expands as the frequency of input vi\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$v_i$$\end{document} increases. The tails of the PGME-3's negative lobe and NMGE-3's positive lobe get longer as the amplitude of vi\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$v_i$$\end{document} gets bigger. This paper proposes a GHz-level memristor emulator consisting of one MOSFET and two diodes, i.e., PGME-1M2D and NGME-1M2D. The operating frequency of the proposed memristor emulator is high up to 10 GHz. The minimum step time of the material implication circuit based on PGME-1M2D and NGME-1M2D is 85 ps. The long tails of PGME-1M2D/NGME-1M2D's ii-vi\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$i_i-v_i$$\end{document} curves do not appear when the amplitude of vi\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemarg

关键词： Drain current  

摘要： This paper presents a novel biosensor, the graded channel gate-all-around (GC-GAA) silicon nanowire-FET biosensor, which utilizes dielectric modulation through a cavity carved from the drain side for label-free biomolecule detection. The biomolecules that become fixed in the cavity region alter the device's electrical properties, such as impedance, resistance, capacitance, and charge field effect, resulting in changes in the biosensing device's threshold voltage, drain current, and sub-threshold slope. The cavity length varies between 10 and 14 nm, and different dielectric constants are used. The study investigates the effect of various biomolecules on the device's performance, including drain current (for dielectric constant = 1 and3.57), sub-threshold slope, threshold voltage, switching ratio, energy band, transconductance, and electric field. The obtained drain currents for device-1 are 2.96 mu A and 2.75 mu A with threshold voltage of 0.78 V and 0.76 V for S_D/D_S graded channel respectively for copper as gate metal. Similarly the drain currents for device-2 are 0.97 mu A and 1.13 mu A with threshold voltage of 0.73 V and 0.68 V for S_D/D_S graded channel respectively. However, for device-3 the drain currents are 0.91 mu A and 1.08 mu A with threshold voltage of 0.73 V and 0.67 V. The results indicate that higher dielectric constants result in higher drain current levels and increased device sensitivity. The GC-GAA-NWFET biosensor demonstrated high sensitivity (similar to 138 mV) and low leakage current, making it a promising candidate for biosensing applications.

关键词： MOSFET driver   power characteristics   integrated driver   high frequency   low-power gate driver  

摘要： This paper presents basic properties and laboratory tests of a commercial integrated high-frequency MOSFET gate driver IXRFD631 operating in the frequency range up to 30 MHz. The MOSFET driver has been tested for two operating states: in the idle state (no load) and at the gate load of a DE275-501N16A series MOSFET transistors. The obtained laboratory results were compared with three other commercial integrated drivers: DEIC420, DEIC515 and IXRFD630 (which are the base structures), and two previous solutions from the author (4xUCC27516 and 8xUCC27526). Additionally, this paper presents the characteristics of power losses and efficiency, measurements of switching and propagation times of the tested gate drivers. Also, this paper presents the output voltage waveforms of the integrated driver IXRFD631 for two operating states. The integrated circuit IXRFD631 of the gate driver is characterized by an efficiency of up to 70% for the tested frequency range, the power losses for two operating states (at idle state-15 W, at gate MOSFET load-43 W) and switching times of 2 ns for an operating frequency of 30 MHz.