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关键词： Scattering   MOSFET   Logic gates   Voltage measurement   Magnetic field measurement   Temperature measurement   Doping   Channel mobility   hall measurement   power metal-oxide-semiconductor field-effect-transistors (MOSFET)   specific ON-resistance  

摘要： High critical field (Ec) and low specific ON-resistance (RON) beta-Ga(2)O(3 )devices such as accumulationchannel metal-oxide-semiconductor field-effect-transistors(MOSFET) have been reported for high-power and extremeenvironment applications. Channel carrier mobility is acritical factor to reduceRON, but a lack of studies on channel mobility in beta-Ga2O3 MOSFETs hinders understandingthe electrical characteristics. We study carrier mobility inthe channels with various doping concentrations using MOS-gated Hall measurements. Our MOSFET achieves arecord-high peak channel mobility (mu peak) of 143 cm2/Vs,to the best of our knowledge. Moreover, we suggest that further improvements can be made by enhancing Coulombscattering-limited mobility (mu C)

关键词： Silicon carbide   MOSFET   Thermal resistance   Degradation   Immune system   Temperature measurement   Thermal degradation   Double-side cooling   high-temperature   power cycling test (PCT)   SiC MOSFET  

摘要： Due to the excellent performance of the silicon carbide (SiC) chip, it will increasingly be used in electric vehicle power conversion systems. Among different packaging options, the double-side cooling (DSC) package is considered a superior choice for packing SiC chips due to its exceptional cooling capacity and low parasitic inductance of DSC modules. As DSC modules have multiple interconnections, each interconnection is under different stresses during the power cycling test (PCT). Hence, the degradation of overall thermal resistance and local thermal resistance needs to be evaluated separately during the PCT. In this study, a double-sided cooling (DSC) SiC MOSFET module was fabricated, and its excellent electrical performance was characterized at a high temperature of 175 degrees C. The SiC MOSFET body diode forward voltage of the DSC module was only increased by less than 1.5%, although the local area-accounted thermal resistance and overall thermal resistance increased by 26.03% and 20.51%, respectively. The increase rate of the local thermal resistance is greater than that of the overall thermal resistance due to the different thermo-mechanical strains in each interconnection. Therefore, for the DSC SiC MOSFET modules, it is critical to pay more attention to the local thermal resistance degradation than the overall one.

关键词： Junctionless and Junction-based MOSFETs   Macaroni MOSFETs   Short Channel Effects (SCEs)   Threshold voltage modeling   High-k gate stack  

摘要： This paper presents explicit threshold voltage modeling based comparative threshold voltage exploration of Junctionless (JL) and Junction-based (JB) High-K gate stack (HKGS) Dual-Material (DM) Cylindrical Gate-allaround (CGAA) Macaroni (Mac.) MOSFET. Based on Young's popular Parabolic Potential Approximation (PPA), device features like inner potential has been formulated. Based on the expression of inner potential, threshold voltage has been extracted. Other major short channel effects like Drain-induced barrier lowering (DIBL) and subthreshold swing (SS) have also been analyzed. Device parameters such as inner, outer radii, channel lengths, type of high-k gate oxide, source/drain doping for JB device, etc. have also been varied to examine their effects on device parameters. Finally mathematical outputs have been corroborated with simulation outputs from Atlas.

关键词： Dual -doped source/drain   RFET   MOSFET   TFET   Schottky barrier  

摘要： -In this paper, a reconfigurable field-effect transistor (RFET) with dual-doped nanosheet architecture and triple independent gates is proposed and studied with the numerical simulations. The proposed RFET can behave as either an n/p-type MOSFET or an n/p-type tunneling-FET (TFET) according to different program biases. A comprehensive study is carried out on the device mechanism and the influence of key device parameters. Various metrics, such as the on-state current (ION), off-state current (IOFF), ION/IOFF, threshold voltage (VT) and subthreshold swing (SS), are used to evaluate the proposed RFET. This RFET combining the advantages of the conventional MOSFETs (High ION and operation speed) and the new emerging TFETs (Low IOFF, sub-threshold swing and power dissipation) could make the circuit design more flexible and high efficiency, and improve the circuit performance.

关键词： Fault currents   Prototypes   High-temperature superconductors   Capacitors   Circuit breakers   MOSFET   Aircraft   Cryogenic   DC circuit breaker   sub-cooled liquid nitrogen   superconducting fault current limiter  

摘要： Large-scale electric aircraft are a promising technology that could revolutionise air travel to reduce the environmental impact. Fault current limitation and interruption technology is crucial to realise the safety and reliability of the electric aircraft, in particular for large-scale electric aircraft using a DC distribution network. This article proposes to integrate a resistive superconducting fault current limiter (SFCL) with a cryogenic DC solid-state circuit breaker (SSCB) so that the SFCL limits the fault current to acceptable levels in DC networks allowing the SSCB to operate quickly and reliably. A sub-cooled liquid nitrogen cryostat, which can be controlled from 65 K to 77 K, is designed and built for the integration of SFCL and DC SSCB. An SFCL and SSCB prototype is designed and experimentally tested at cryogenic temperatures, which successfully demonstrates the ability to limit and interrupt currents at cryogenic environment.

关键词： SiC MOSFET   fin-channel   gate shielding effect   dynamic threshold voltage  

摘要： A SiC fin-channel MOSFET structure (Fin-MOS) is proposed for an enhanced gate shielding effect. The gates are placed on each side of the narrow fin-channel region, while grounded p-shield regions below the gates provide a strong shielding effect. The device is investigated using Sentaurus TCAD. For a narrow fin-channel region, there is difficulty in forming an Ohmic contact to the p-base;a floating p-base might potentially store negative charges upon high drain voltage, and, thus, causes threshold voltage instabilities. The simulation reveals that, for a fin-width of 0.2 mu m, the p-shield regions provide a stringent shielding effect against high drain voltage, and the dynamic threshold voltage shift (triangle Vth) is negligible. Compared to conventional trench MOSFET (Trench-MOS) and asymmetric trench MOSFET (Asym-MOS), the proposed Fin-MOS boasts the lowest OFF-state oxide field and reverse transfer capacitance (Crss), while maintaining a similar low ON-resistance.

关键词： Resistance   MOSFET   Cryogenics   Voltage measurement   Logic gates   Electrical resistance measurement   Threshold voltage   Cryogenic characterization   power applications   power electronics   silicon  

摘要： To reduce fuel consumption and CO2 emissions, an effort has been made in aircraft industry to investigate a superconducting application requiring an on-board cryogenic system. In this investigation, the question of cryogenic power electronics arose in an effort to reduce losses. Switches are the core of power electronics converters, which means that reducing their losses is a key point for the whole converter. But cryogenic temperatures may alter their behavior due to material contractions and changes in charge carrier behavior. It is therefore important to determine the optimum temperature for the switches, or at least the range within which there is a compromise between reducing losses and ensuring that the switches behave correctly. The Si-MOSFET was initially chosen to better understand the behavior of a single material at cryogenic temperature. The main losses of the MOSFET come from the Drain-Source resistance R-DSON. In addition, to ensure the switch operates correctly, the evolution of the voltage threshold V-TH as a function of temperature must be determined. This paper presents new results on the study of R-DSON Drain-Source resistance at cryogenic temperatures. Results and discussions are also conducted on the V-TH voltage threshold and I-D(V-DS) curves of an industrial Si power MOSFET from 300 K down to 10 K.

关键词： overshoot   oscillation   active gate circuit adjustment   turn-on and turn-off detection  

摘要： Due to the influence of parasitic internal parameters and junction capacitance, the silicon carbide (SiC) power devices are frequently marred by significant overshoots in current and voltage, as well as high-frequency oscillations during the switching process. These phenomena can severely compromise the reliability of SiC-based power electronic converters during operation. This study delves into the switching transient of the SiC MOSFET with the goal of establishing a quantitative correlation between the gate driving current and the overshoot in both the drain-source voltage and the drain current. In light of these findings, the innovative active gate drive (AGD) circuit, which features an adjustable gate current, is introduced. Throughout the switching process, the AGD circuit employs a dynamic monitoring and feedback mechanism that is responsive to the gate voltage and rate of change in the drain-source voltage and drain current of the SiC MOSFET. This adjustment enables gate driving current to be actively modified, thereby effectively mitigating the occurrence of overshoots and oscillations. To empirically validate the efficacy of the proposed AGD circuit in curbing voltage and current overshoots and oscillations, a double-pulse experimental setup was meticulously constructed and tested.

关键词： trench MOSFET   power semiconductor devices   4H-SiC   high-K dielectric   breakdown voltage   specific on-resistance  

摘要： This paper proposes and investigates a novel 4H-SiC trench MOSFET (TMOS) with integrated high-K deep trench and gate dielectric (INHK-TMOS). The integrated high-K (INHK) consists of a high-K gate dielectric and an extended high-K deep trench dielectric in the drift region. Firstly, the high-K gate dielectric together with the metal-forming high-K metal gate structure, which increases the gate oxide capacitance (C-OX), reduces the threshold voltage (V-TH) and the specific on-resistance (R-on,R-sp). Secondly, the extended high-K deep trench dielectric not only modulates the electric field in the drift region by introducing a new electric field peak at the bottom of the high-K deep trench dielectric, thereby enhancing the breakdown voltage (BV), but also improves the doping concentration (N-D) of the drift region by the assist depletion effect of the high-K dielectric, further optimizing the forward conduction characteristics. Simulation results demonstrate that when compared to the conventional TMOS, the INHK-TMOS using HfO2 exhibits a 52.6% reduction in V-TH, a 52.1% reduction in R-on,R-sp, a 20.3% increasement in BV and a 202.3% improvement in figure of merit.

关键词： Current detection   overcurrent protection   silicon carbide (SiC) MOSFET   soft turn-OFF circuit  

摘要： This letter proposes a fast overcurrent protection integrated circuit (IC) for silicon carbide (SiC) mosfet based on current detection. With the proposed protection IC, the voltage between the Kelvin source and power source of SiC mosfet is sensed through an off-chip resistance. Thus, a detection voltage proportional to the drain current of SiC mosfet is obtained. Comparing the detection voltage to on-chip reference voltages, the proposed protection IC can provide both overload (OL) and short circuit (SC) protections for SiC mosfet. Moreover, a soft turn-off circuit is integrated into the protection IC. The proposed protection IC is implemented in a 0.5-mu m bipolar-CMOS-DMOS process and the die size is about 2 mm(2). With the 1200 V/80 m Omega SiC mosfet, the proposed protection IC is verified on our test bench. With the proposed protection IC, the response time of the SC protection is 24 ns and the SC duration time of the SiC mosfet is 43 ns. Owing to the soft turn-off circuit of the protection IC, the drain voltage overshoot of the SiC mosfet is lower than 90 V during the OL and SC protections.