- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
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
-
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
-
[IEEE 2018 IEEE 5G World Forum (5GWF) - Silicon Valley, CA, USA (2018.7.9-2018.7.11)] 2018 IEEE 5G World Forum (5GWF) - Packaged High Power Frond-End Module for Broadband 24GHz & 28GHz 5G solutions
摘要： This paper presents realization and characteristics of broadband plastic low cost packaged 5G High Power Frond-End (HPFE) operating in 24-31GHz bandwidth. This demonstrator includes a Transmit and Receive paths realized on mixed technologies: 150nm Gallium Nitride on Silicon Carbide (AlGaN/GaN on SiC) and 150nm Gallium Arsenide (GaAs). Continuous Wave (CW) measured power results of the Transmit path (Tx) demonstrates a maximum output power (POUT,Tx) higher than 2W (33.5dBm) with 25% drain efficiency (DE), 24% power added efficiency (PAE), and 36dB of insertion gain (GI,Tx) in the 24-31GHz bandwidth. The receiver path (Rx) presents an maximum output power (POUT,Rx) of 30mW (15.5dBm) and an average Noise Figure (NF) of 3.6dB with an associated Insertion Gain (GI,Rx) of 20dB in the same bandwidth. The HPFE/Tx linearity has been investigated with several M-QAM modulation signals with 25/50 and 100MHz channel spacing and using Digital Pre-Distortion (DPD) leading to 48dBc Adjacent Channel Leakage Ratio (ACLR) and 40dB Mean Squared Error (MSE) for average output powers ranging from linearity performances have been 17dBm to 25dBm. The compared to the ones obtained with two other linear GaAs amplifiers to point telecommunications application: the HPFE presents similar linearity performances associated to a higher efficiency. Thanks to the mixed technologies approach, an optimized trade-off in terms of integration, electrical performances and cost has been demonstrated.
关键词： MMIC,PHEMT,Gallium Arsenide,Plastic packaging,Transmit/Receive path,Low Noise Amplifier,Gallium Nitride,Power Amplifier,Switch
更新于2025-09-23 15:21:01
-
Coupled thermoa??electrical analysis of highly scaled GaN micro-LEDs with meshed hybrid conductors
摘要： Display technology with ultrafine pixels for near-eye application is a rapidly growing field due to the recent emergence of augmented/mixed reality. With the constant demand for high energy efficiency, long lifetime, and high luminosity, micro-LED displays based on compound semiconductors are promising candidates for such applications. However, miniaturizing LEDs results in significant drawbacks in terms of their quantum efficiency, current injection efficiency, and heat extraction. With relatively low device resistance compared to that of liquid crystals or organic LEDs, micro-LEDs are also more susceptible to the effects of parasitic resistance. In this study, gallium nitride based micro-LED displays with very small pixels (5 μm pixel, 10 μm pitch) are fabricated to study the thermal–electrical effect of meshed hybrid conductors on the optical emission efficiency. In situ thermographic imaging with I–V measurement confirms a significant trade-off among heat transfer, electrical conductivity, and light extraction efficiency. An increase of 37.9 % in the emission efficiency (2,540 PPI, 5 μm pixels, 1 mm2 display, at 49.2 ℃) is achieved by optimizing the thermal and electrical conduction paths. This study experimentally confirms the importance of thermal management and multi-physics analysis in designing ultra-small-pixel micro-LEDs with high energy efficiency.
关键词： hybrid transparent conductor,Thermo–electrical analysis,gallium nitride,micro-LED
更新于2025-09-23 15:21:01
-
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
-
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
-
[IEEE 2018 XIII International Conference on Electrical Machines (ICEM) - Alexandroupoli, Greece (2018.9.3-2018.9.6)] 2018 XIII International Conference on Electrical Machines (ICEM) - Design of a GaN Based Integrated Modular Motor Drive
摘要： In this study, design procedure of an Integrated Modular Motor Drive (IMMD) is presented focusing on high power density. The design is based on a permanent magnet synchronous motor (PMSM) and GaN FETs. Fractional slot concentrated windings are used on the stator. Slot/pole combination and winding configuration is selected based on having low cogging torque and high winding factor. An extended motor drive inverter topology is proposed where 2-level voltage source inverters are connected both in series and parallel. Optimum selection of number of modules is discussed and power semiconductor devices are selected based on loss characterization. Optimum DC link capacitor bank is determined and the effect of interleaving is investigated. The performance of the motor is validated with ANSYS/Maxwell simulations. Motor drive performance is obtained with MATLAB/Simulink simulations. The efficiency of the motor drive is enhanced by 2% compared to a conventional motor drive. An overall system power density over 1 kW/lt has been achieved with the proposed series/parallel motor drive configuration having GaN FETs.
关键词： Permanent magnet synchronous motor,Modular motor,Power density,Gallium nitride,Integrated motor drive
更新于2025-09-23 15:21:01
-
Near-ultraviolet Raman and micro-Raman analysis of electronic materials
摘要： Raman and micro-Raman analysis methods have been extensively investigated for the study of materials used in electronic and photonic devices. Raman studies are used to understand fundamental phonon properties, along with effects related to the crystal structure, disorder, doping, and external factors such as temperature and stress. Micro-Raman extends these investigations to the micron scale. This article reviews diverse benefits of Raman measurements when carried out using laser excitation in the near-ultraviolet wavelength range, nominally 400 to 325 nm. Micro-Raman methods in the near ultraviolet exploit the key advantage of reduced focal spot size, achievable at shorter wavelengths when using diffraction-limited optics, for mapping with high spatial resolution. There are distinct advantages common to Raman and micro-Raman spectroscopy in the near ultraviolet when compared to the widely used visible excitation. One advantage exploits the shallower optical penetration depth in select materials for probing near-surface regions or interfaces. A second advantage is related to tuning of the excitation photon energy relative to the electronic levels of a material for investigating resonance effects. Finally, the application of Raman scattering to materials which exhibit strong fluorescence requires tuning to a wavelength range away from the potentially obscuring emission. This article overviews several examples of these key advantages to study diverse applied physics problems in electronic and photonic materials. Topics covered include stress mapping in silicon and related materials, stress and thermal effects in gallium nitride and other group-III-nitride semiconductors, and carbon materials ranging from graphite and graphene to diamond grown using chemical vapor deposition. The fundamental effects of stress- and temperature-induced shifts in phonon energies and their application to study epitaxy and device-related effects are also briefly reviewed.
关键词： near-ultraviolet,stress mapping,carbon materials,chemical vapor deposition,phonon properties,Raman spectroscopy,electronic materials,micro-Raman,gallium nitride
更新于2025-09-23 15:21:01
-
Quantum dots power polarizing light source
摘要： A new way of generating linearly polarized photons using quantum dots has been developed by an international team of researchers. The novel source of polarized light could be used to develop energy-saving computers and mobile-phone screens, as well as secure communications. Researchers have long studied quantum dots and their many possible applications, but getting them to emit photons that have a predefined polarization has proved difficult and this is an essential requirement for many applications.
关键词： quantum dots,polarized light,InGaN,gallium-nitride pyramids,indium gallium nitride
更新于2025-09-23 15:19:57
-
[IEEE 2019 International Conference on Electrical, Electronics and Computer Engineering (UPCON) - ALIGARH, India (2019.11.8-2019.11.10)] 2019 International Conference on Electrical, Electronics and Computer Engineering (UPCON) - A Study on the Influence of Open Circuit Voltage (Voc) and Short Circuit Current (Isc) on Maximum Power Generated in a Photovoltaic Module/Array
摘要： A technique is described, to efficiently evaluate the reliability of an RF semiconductor device when several different mechanisms contribute simultaneously to its wearout. This is of interest for present-day GaN HEMT devices because symptoms of several simultaneous degradation mechanisms have been reported widely. The technique involves first finding DC parameters that are “signatures” of each mechanism. Then, separate DC-stress lifetests are performed to find the degradation rates for the signature parameters, at several temperatures, and the corresponding Arrhenius curves. Next, an RF-stress lifetest (with only one stress condition) is performed, while monitoring all of the signature parameters and the RF performance. This is utilized to determine the “scaling factors” between the rates of change in the DC lifetests and the rates of change in the RF application. Applying these scaling factors to the original Arrhenius curves gives an “overall” Arrhenius plot for the RF application with several different lines, for the different degradation mechanisms. The technique can be extended to further degradation mechanisms, by conducting further DC and RF lifetests while monitoring appropriate signature parameters.
关键词： semiconductor device reliability,lifetesting,gallium nitride,HEMTs,Failure analysis
更新于2025-09-23 15:19:57