- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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Gate Conduction Mechanisms and Lifetime Modeling of p-Gate AlGaN/GaN High-Electron-Mobility Transistors
摘要： The gate conduction mechanisms in p-gallium nitride (GaN)/AlGaN/GaN enhancement mode transistors are investigated using temperature-dependent dc gate current measurements. In each of the different gate voltage regions, a physical model is proposed and compared to experiment. At negative gate bias, Poole–Frenkel emission (PFE) occurs within the passivation dielectric from gate to source. At positive gate bias, the p-GaN/AlGaN/GaN “p-i-n” diode is in forward operation mode, and the gate current is limited by hole supply at the Schottky contact. At low gate voltages, the current is governed by thermionic emission with Schottky barrier lowering in dislocation lines. Increasing the gate voltage and temperature results in thermally assisted tunneling (TAT) across the same barrier. An improved gate process reduces the gate current in the positive gate bias region and eliminates the onset of TAT. However, at high positive gate bias, a sharp increase in current is observed originating from PFE at the metal/p-GaN interface. Using the extracted conduction mechanisms for both devices, accurate lifetime models are constructed. The device fabricated with the novel gate process exhibits a maximum gate voltage of 7.2 V at t1% = 10 years.
关键词： time-dependent breakdown (TDB),p-GaN gate,high-electron-mobility transistor (HEMT),enhancement mode,gallium nitride (GaN),Conduction mechanism
更新于2025-09-23 15:21:21
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Design of a Compact GaN MMIC Doherty Power Amplifier and System Level Analysis With X-Parameters for 5G Communications
摘要： This paper presents a monolithic microwave integrated circuit Doherty power amplifier (DPA) operating at sub-6 GHz for 5G communication applications by a 0.25-μm gallium nitride high-electron mobility transistor process. A compact impedance inverter and output matching of the DPA are achieved using a transmission line network and shunt capacitors. Also, the size ratio of power cells in the main and auxiliary amplifiers is optimized for a high efficiency at output power backoff (OPBO). The measured peak output power (Pout) and the 1-dB compression point (P1 dB) are 38.7 and 32.1 dBm, respectively, at 5.9 GHz. The power-added efficiency at 6-dB OPBO is up to 49.5%. Without digital predistortion (DPD), the DPA can deliver an average Pout of 23.5 dBm with error vector magnitude (EVM) <?28 dB and 21.5 dBm with EVM <?32 dB for 64-quadrature amplitude modulation (QAM) and 256-QAM signals, respectively. The measured X-parameters are employed to further investigate the DPA nonlinear characteristics and verify the accuracy of conventionally used power amplifier characterization/measurement methods for system-level design and testing applications. The simulated results based on the X-parameters also indicate that the average output power can be enhanced up to 25.7 dBm with DPD for 256-QAM.
关键词： 5G communication,monolithic microwave integrated circuit (MMIC),X-parameters,power-added efficiency (PAE),power amplifier (PA),Doherty,gallium nitride (GaN)
更新于2025-09-23 15:21:21
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Designing Beveled Edge Termination in GaN Vertical p-i-n Diode-Bevel Angle, Doping, and Passivation
摘要： A series of electric field profile simulations in gallium nitride (GaN) p-i-n vertical diodes with negative bevel termination is carried out to optimize the bevel design. The bevel angles are varied from 90? to 0.1? with reasonably small increments to study the impact of the bevel angle on the electric field profile. The doping densities are also varied to study a more generalized trend; a new parameter defined as transition angle θt is proposed to characterize the effectivity of a beveled edge termination. Considering the potential dry etch damage on the bevel side-wall during device fabrication, the fixed surface charge from the dangling bonds and commonly used dielectric passivation are also added separately to investigate their influence. This article presents a comprehensive simulation study of GaN p-i-n diode with negative beveled edge termination, making it a useful guide for designing a simple and effective beveled edge termination, which eventually helps to enable the routine avalanche in GaN p-i-n diodes.
关键词： beveled edge termination,surface charge,simulation,gallium nitride (GaN),transition angle,silvaco,passivation,p-i-n diode,Avalanche,TCAD
更新于2025-09-23 15:21:01
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92.5% Average Power Efficiency Fully Integrated Floating Buck Quasi-Resonant LED Drivers Using GaN FETs
摘要： LEDs are highly energy ef?cient and have substantially longer lifetimes compared to other existing lighting technologies. In order to facilitate the new generation of LED devices, approaches to improve power ef?ciency with increased integration level for lighting device should be analysed. This paper proposes a fully on-chip integrated LED driver design implemented using heterogeneous integration of gallium nitride (GaN) devices atop BCD circuits. The performance of the proposed design is then compared with the conventional fully on-board integration of power devices with the LED driver integrated circuit (IC). The experimental results con?rm that the fully on-chip integrated LED driver achieves a consistently higher power ef?ciency value compared with the fully on-board design within the input voltage range of 4.5–5.5 V. The maximal percentage improvement in the ef?ciency of the on-chip solution compared with the on-board solution is 18%.
关键词： fully on-chip,gallium nitride (GaN),?oating buck converter,complementary-metal-oxide-semiconductor (CMOS),quasi resonance,integrated LED driver,heterogeneous integration
更新于2025-09-23 15:21:01
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Exploring optical properties of Gd doped zincblende GaN for novel optoelectronic applications (A DFT+U study)
摘要： In current research, we investigate optical properties of Gd doped zincblende GaN using Wien2K code, by employing DFT+U. We consider pure GaN and we dope various Gd concentrations 3.12%, 6.25% and 12.5% into the host GaN lattice while supercell size is kept fixed (1×2×2) for all cases. We elaborate and present a detailed comparison among optical and electronic properties of pure GaN with various Gd concentrations. Interaction of Gd and N atoms and localization of d and f states of dopant are remarked near Fermi level or maxima of valence band. In comparison to pure GaN, absorption spectra for 3.12% Gd concentration shows redshift but for highest Gd concentration (6.25% 12.5%), a blueshift in absorption spectrum is noted. Absorption is pronounced and enhanced in the UV region. Study of optical spectra for various optical properties suggest that Gd:GaN system is mostly suitable for UV optoelectronics. Results for optical properties have great similarity with the existing literature works. Our unprecedented and first ever reported results on optical properties of Gd:GaN system, direct future path of this material for its potential uses in UV optoelectronic, photonic, LEDs, UV sterilization application, photosensors, thermochromic solar cells and biochemical sensing industries.
关键词： optical properties,density of states,DFT calculations,gallium nitride (GaN),Gd doping
更新于2025-09-23 15:19:57
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[IEEE 2019 5th International Conference on Advances in Electrical Engineering (ICAEE) - Dhaka, Bangladesh (2019.9.26-2019.9.28)] 2019 5th International Conference on Advances in Electrical Engineering (ICAEE) - Comparative Study of Different Transformer-less Inverter Topologies for Grid-tied Photovoltaic System
摘要： An inductively coupled contactless dc connector has been proposed for the next-generation 380-V dc distribution system in data centers. A LLC resonant dc–dc converter topology with gallium nitride (GaN) power transistors has been applied to realize the short-distance highly ef?cient contactless power transfer. A prototype of a 1.2-kW 384- to 192-V connector has been fabricated and the conversion ef?ciency of over 95% with the power density of 8.1 W/cm3 has been con?rmed experimentally under 1000-kHz operation. The design consideration has been carried out and the potential to achieve 10.0 W/cm3 has been also shown taking the feature of the GaN power device and the characteristics of the magnetic core material for the transformer into account. The contactless dc connector integrates the functioning of an isolated dc–dc converter into a connector for space saving, and the dc current can be cut off without arc because of the inductive coupling. The proposed connector contributes to realizing a highly ef?cient, space saving, and reliable future 380-V dc distribution system.
关键词： Contactless power supply,dc–dc power converters,dc power distribution,gallium nitride (GaN)
更新于2025-09-19 17:13:59
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[IEEE 2017 IEEE 44th Photovoltaic Specialists Conference (PVSC) - Washington, DC (2017.6.25-2017.6.30)] 2017 IEEE 44th Photovoltaic Specialist Conference (PVSC) - Characterization and redesign of perovskite/silicon tandem cells
摘要： An inductively coupled contactless dc connector has been proposed for the next-generation 380-V dc distribution system in data centers. A LLC resonant dc–dc converter topology with gallium nitride (GaN) power transistors has been applied to realize the short-distance highly ef?cient contactless power transfer. A prototype of a 1.2-kW 384- to 192-V connector has been fabricated and the conversion ef?ciency of over 95% with the power density of 8.1 W/cm3 has been con?rmed experimentally under 1000-kHz operation. The design consideration has been carried out and the potential to achieve 10.0 W/cm3 has been also shown taking the feature of the GaN power device and the characteristics of the magnetic core material for the transformer into account. The contactless dc connector integrates the functioning of an isolated dc–dc converter into a connector for space saving, and the dc current can be cut off without arc because of the inductive coupling. The proposed connector contributes to realizing a highly ef?cient, space saving, and reliable future 380-V dc distribution system.
关键词： dc power distribution,Contactless power supply,dc–dc power converters,gallium nitride (GaN)
更新于2025-09-19 17:13:59
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Local atomic structure of the GaN-side of the Al2O3/GaN interface revealed by X-ray absorption spectroscopy
摘要： The interface between a gate insulator (Al2O3) and a semiconductor (GaN) was investigated via surface-sensitive Ga K-edge extended X-ray absorption fine structure spectroscopy, achieved by detecting the Ga LMM Auger electrons originated from the Ga K-shell absorption. This GaN-side interface study was conducted on Al2O3 thin films formed via atomic layer deposition. The determined atomic structures revealed GaN crystalline changes and the formation of Ga–O bonds due to nitrogen annealing.
关键词： Aluminum oxide (Al2O3),Interface,Post-deposition annealing (PDA),Gallium nitride (GaN),Extended X-ray absorption fine structure (EXAFS),Atomic layer deposition (ALD)
更新于2025-09-19 17:13:59
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[IEEE 2018 IEEE 7th World Conference on Photovoltaic Energy Conversion (WCPEC) (A Joint Conference of 45th IEEE PVSC, 28th PVSEC & 34th EU PVSEC) - Waikoloa Village, HI (2018.6.10-2018.6.15)] 2018 IEEE 7th World Conference on Photovoltaic Energy Conversion (WCPEC) (A Joint Conference of 45th IEEE PVSC, 28th PVSEC & 34th EU PVSEC) - Opto-electrical Properties of GaN/Si Nanoheterostructure Array Device
摘要： A GaN/Si nanoheterostructure array was synthesized using the functional substrate of silicon nanoporous pillar array (Si-NPA) by CVD method. An n-GaN nanocolumnar/p-Si nanocrystalline nanoheterojuction array solar cell was fabricated and the GaN nanocolumnar grew along the [0001] direction. The device has an average integrated reflection of ~4.79% at the range of 300-1200 nm. The solar cell showed a Voc of 0.82 V, a Jsc of 23.21 mA, a FF of 38.3% and a maximum power conversion efficiency of 7.29%. The results provide a new conception of mass-nanoheterojuctions for photovoltaic filed.
关键词： Solar cells,Gallium nitride (GaN),Nanoheterostructure array,Silicon nanoporous pillar array (Si-NPA)
更新于2025-09-11 14:15:04
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Hot-Electron Trapping and Hole-Induced Detrapping in GaN-Based GITs and HD-GITs
摘要： This paper investigates the trapping mechanisms in gate-injection transistors (GITs) without and with a pdrain electrode, referred to as GITs and Hybrid-Drain-embedded GITs (HD-GITs), respectively, used to inject holes and reduce charge trapping effects. We compare the two sets of devices under both the OFF-state and semi-ON state, to investigate the role of hot electrons in favoring the charge trapping. The analysis is based on combined pulsed characterization, transient measurements, and electroluminescence (EL) characterization. We demonstrate the following relevant results: 1) GITs and HD-GITs have comparable and negligible dynamic RON when trapping is induced in the OFF-state; under semi-ON state conditions, GITs suffer from significant dynamic RON, while HD-GITs show no additional trapping with respect to OFF-state; 2) EL characterization carried out until VDS = 500 V in semi-ON conditions shows comparable features, suggesting that the electric field and hot-carrier density are similar in GITs and HD-GITs. This result indicates that the hot-electron trapping rate is identical for the two sets of samples, so the difference observed in dynamic RON must be ascribed to a different detrapping rate; 3) transient RON measurements indicate that the traps filled in the OFF-state conditions are the same as those filled by hot electrons in semi-ON, with Ea = 0.8 eV (possibly CN); and 4) EL analysis under constant bias indicates that in GITs there is a time-dependent increase in the luminescence signal at the drain terminal, when the devices are biased with VDS = 300 V. Such effect, indicative of hot-electron trapping, is not observed in HD-GITs. Based on the experimental evidence collected within this paper, we conclude that—in the semi-ON state—the main difference between GITs and HD-GITs consists in a faster detrapping rate of hot electrons, achieved through hole injection from the pdrain terminal.
关键词： gate-injection transistors (GITs),Electroluminescence (EL),gallium nitride (GaN) HEMT,trapping,hot electron
更新于2025-09-10 09:29:36