共查询到20条相似文献,搜索用时 0 毫秒
1.
《Electron Device Letters, IEEE》2009,30(11):1122-1124
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在SiC衬底上制备了栅长为110 nm、漏源间距为2μm的W波段AlGaN/GaN高电子迁移率场效应晶体管(HEMT),分析了SiN钝化对器件直流和射频特性的影响.研究发现:100 nm SiN钝化可显著提升器件的漏源饱和电流及峰值跨导,漏源饱和电流从1.27 A/mm增加至1.45 A/mm (Vgs=1 V),器件峰值跨导从300 mS/mm提升至370 mS/mm,这是由于SiN钝化显著提高了AlGaN/GaN异质结材料沟道电子浓度.此外,SiN钝化可有效抑制器件电流崩塌,显著改善器件直流回扫特性.然而,由于沟道电子浓度增大,钝化后器件中短沟效应增强,器件夹断特性变差.此外,SiN钝化后W波段AlGaN/GaN HEMTs的射频特性得到显著改善,器件的电流增益截止频率从钝化前的33 GHz提升至107 GHz,最高振荡频率从钝化前的65 GHz提升至156 GHz. 相似文献
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研究了蓝宝石衬底AlGaN/GaN共栅共源器件的特性。该器件包括栅长0.8μm共源器件与栅长1μm的共栅器件。研究表明,共栅共源器件的第二栅压对的器件饱和电流与跨导有明显的调制作用,容易实现功率增益控制。与共源器件相比,共栅共源器件在微波特性上fT大约9GHz,比共源器件稍小,但是具有较低的反馈,显著增加的功率资用增益及较高的端口阻抗,与共源器件相比,稳定性更好,可以避免振荡的产生,结合GaN的高功率特性GaN共栅共源器件非常适合微波频段宽频大功率领域的应用。 相似文献
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提出一种新的钝化技术--采用盐酸和氢氟酸混合预处理溶液(HF:HCI:H2O=1:4:20)对AIGaN/GaNHEMTs进行表面预处理后冉淀积Si3N4钝化,研究了新型钝化技术对AlGaN/GaN HEMTs性能的影响并分析其机理.与用常规方法钝化的器件相比,经过表面顶处理再钝化,成功地抑制了 AIGaN/GaN HEMTs肖特基特性的恶化,有效地增强抑制电流崩塌效应的能力,将GaN基HEMTs的输出功率密度提高到5.2W/mm,并展现良好的电学可靠性.通过X射线光电子谱(XPS)检测预处理前后的AIGaN表面,观察到经过预处理后的AIGaN表面氧元素的含量大幅度下降.表面氧元素的含量下降,能有效地降低表面态密度和表面电荷陷阱密度,被认为是提高AIGaN/GaN HEMTs性能的主要原因. 相似文献
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《Electron Device Letters, IEEE》2009,30(8):808-810
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研究了SiN钝化前利用感应耦合等离子体(ICP)对AlGaN/GaN HEMT表面进行NF3等离子体处理对器件性能的影响. 结果表明,运用低能量的NF3等离子体处理钝化前的AlGaN/GaN HEMT表面能有效抑制器件电流崩塌,而器件直流及微波小信号特性则未受影响. 微波功率测试表明,经过6min NF3等离子体处理的AlGaN/GaN HEMT在2GHz, 30V工作电压下达到6.15W/mm的输出功率密度,而未经过处理的器件只达到1.82W/mm的输出功率密度. 相似文献
7.
Das J. Oprins H. Ji H. Sarua A. Ruythooren W. Derluyn J. Kuball M. Germain M. Borghs G. 《Electron Devices, IEEE Transactions on》2006,53(11):2696-2702
AlGaN/GaN high electron mobility transistors (HEMT) on sapphire substrates have been studied for their potential application in RF power applications; however, the low thermal conductivity of the sapphire substrate is a major drawback. Aiming at RF system-in-a-package, the authors propose a flip-chip-integration approach, where the generated heat is dissipated to an AlN carrier substrate. Different flip-chip-bump designs are compared, using thermal simulations, electrical measurements, micro-Raman spectroscopy, and infrared thermography. The authors show that a novel bump design, where bumps are placed directly onto both source and drain ohmic contacts, improves the thermal performance of the HEMT 相似文献
8.
Malek Gassoumi Hana Mosbahi Ali Soltani Vanessa Sbrugnera-Avramovic Mohamed Ali Zaidi Christophe Gaquiere Houcine Mejri Hassen Maaref 《Materials Science in Semiconductor Processing》2013,16(6):1775-1778
AlGaN/GaN/Si high electron mobility transistors (HEMTs) grown by molecular beam epitaxy are investigated using direct-current and radio-frequency measurements. As has been found, the maximum of drain current achieves 881 mA/mm with an extrinsic current gain cutoff frequency of 37 GHz for a 0.25 µm gate length. Pulsed characteristics also showed a reduction of trapping centers that improves the quality of the epilayers. 相似文献
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The advent of fully integrated GaN PA-LNA circuits makes it meaningful to investigate the noise performance under high drain bias. However, noise performance of AlGaN/GaN HEMTs under high bias has not received worldwide attention in theoretical studies due to its complicated mechanisms. The noise value is moderately higher and its rate of increase is fast with increasing high voltage. In this paper, several possible mechanisms are proposed to be responsible for it. Impact ionization under high electric field incurs great fluctuation of carrier density, which increases the drain diffusion noise. Besides, higher gate leakage current related shot noise and a more severe self-heating effect are also contributors to the noise increase at high bias. Analysis from macroscopic and microscopic perspectives can help us to design new device structures to improve noise performance of AlGaN/GaN HEMTs under high bias. 相似文献
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rom macroscopic and microscopic perspectives can help us to design new device structures to improve noise performance of AlGaN/GaN HEMTs under high bias. 相似文献
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14.
提出一种新的钝化技术--采用盐酸和氢氟酸混合预处理溶液(HF:HCI:H2O=1:4:20)对AIGaN/GaNHEMTs进行表面预处理后冉淀积Si3N4钝化,研究了新型钝化技术对AlGaN/GaN HEMTs性能的影响并分析其机理.与用常规方法钝化的器件相比,经过表面顶处理再钝化,成功地抑制了 AIGaN/GaN HEMTs肖特基特性的恶化,有效地增强抑制电流崩塌效应的能力,将GaN基HEMTs的输出功率密度提高到5.2W/mm,并展现良好的电学可靠性.通过X射线光电子谱(XPS)检测预处理前后的AIGaN表面,观察到经过预处理后的AIGaN表面氧元素的含量大幅度下降.表面氧元素的含量下降,能有效地降低表面态密度和表面电荷陷阱密度,被认为是提高AIGaN/GaN HEMTs性能的主要原因. 相似文献
15.
Cordier Y. Semond F. Massies J. Dessertene B. Cassette S. Surrugue M. Adam D. Delage S.L. 《Electronics letters》2002,38(2):91-92
Al0.3Ga0.7N/GaN high electron mobility transistor (HEMT) structures have been grown on resistive Si(111) substrate by molecular beam epitaxy (MBE) using ammonia (NH3). The use of an AlN/GaN intermediate layer allows a resistive buffer layer to be obtained. High sheet carrier density and high electron mobility arc obtained in the channel. A device with 0.5 μm gate length has been realised exhibiting a maximum extrinsic transconductance of 160 mS/mm and drain-source current exceeding 600 mA/mm. Small-signal measurements show ft of 17 GHz and fmax of 40 GHz 相似文献
16.
High-performance E-mode AlGaN/GaN HEMTs 总被引:1,自引:0,他引:1
Palacios T. Suh C.-S. Chakraborty A. Keller S. DenBaars S.P. Mishra U.K. 《Electron Device Letters, IEEE》2006,27(6):428-430
Enhancement-mode AlGaN/GaN high electron-mobility transistors have been fabricated with a gate length of 160 nm. The use of gate recess combined with a fluorine-based surface treatment under the gate produced devices with a threshold voltage of +0.1 V. The combination of very high transconductance (> 400 mS/mm) and low gate leakage allows unprecedented output current levels in excess of 1.2 A/mm. The small signal performance of these enhancement-mode devices shows a record current cutoff frequency (f/sub T/) of 85 GHz and a power gain cutoff frequency (f/sub max/) of 150 GHz. 相似文献
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Temperature-dependent nonlinearities of GaN/AlGaN HEMTs are reported. The large-signal device model of the transistor is obtained by using a physics-based analysis. The model parameters are obtained as functions of bias voltages and temperature. The analysis of the device has been carried out using a time-domain technique. fmax for a 0.23 μm×100 μm Al0.13Ga0.87N/GaN FET is calculated as 69 GHz at 300 K, while at 500 K, fmax decreases to 30 GHz, which are in agreement with the experimental data within 7% error. fmax as obtained from calculated unilateral gain, decreases monotonically with increasing temperature. For shorter gate lengths irrespective of the operating temperature fmax is less sensitive to bias voltage scaling. For longer gate length devices, fmax becomes less sensitive to the bias voltage scaling at elevated temperatures. 1-dB compression point (P1-dB ) at 4 GHz for a 1 μm×500 μm Al0.15Ga0.85N/GaN FET is 13 dBm at 300 K. At 500 K, P1-dB decreases to 2.5 dBm for the same operating frequency. Similar results for output referred third intercept point (OIP3) are reported for different gate length devices 相似文献
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Microwave Performance of AlGaN/GaN High-Electron-Mobility Transistors on Si/SiO2/Poly-SiC Substrates
T.J. Anderson F. Ren J. Kim J. Lin M. Hlad B.P. Gila L. Voss S.J. Pearton P. Bove H. Lahreche J. Thuret 《Journal of Electronic Materials》2008,37(4):384-387
The radiofrequency (RF) performance of AlGaN/GaN high-electron-mobility transistors (HEMTs) grown by molecular beam epitaxy
(MBE) on Si-on-poly-SiC (SopSiC) substrates formed by the Smart-CutTM process is reported. This provides a low-cost, high-thermal-conductivity substrate for power applications. HEMTs with a 0.5 μm gate length show cutoff frequencies (f
T) of 18 to 27 GHz for gate-to-drain distances of 3 to 32 μm and a maximum frequency of oscillation (f
max) of 43 to 47 GHz. The f
max values are slightly lower than comparable devices on sapphire, SiC or Si alone. This approach looks promising for applications
requiring cheap large-area substrates and better thermal management than provided by pure Si substrates alone. 相似文献
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Enhancement-mode AlGaN/GaN HEMTs on silicon substrate 总被引:3,自引:0,他引:3
Shuo Jia Yong Cai Deliang Wang Baoshun Zhang Lau K.M. Chen K.J. 《Electron Devices, IEEE Transactions on》2006,53(6):1474-1477
High-performance enhancement-mode AlGaN/GaN HEMTs (E-HEMTs) were demonstrated with samples grown on a low-cost silicon substrate for the first time. The fabrication process is based on a fluoride-based plasma treatment of the gate region and postgate annealing at 450 /spl deg/C. The fabricated E-HEMTs have nearly the same peak transconductance (G/sub m/) and cutoff frequencies as the conventional depletion-mode HEMTs fabricated on the same wafer, suggesting little mobility degradation caused by the plasma treatment. 相似文献
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研究了蓝宝石衬底AlGaN/GaN HEMT器件直流和微波性能随温度的变化。研究结果表明,器件直流性能随着温度升高逐渐下降,350°C时直流性能依然良好,从350°C冷却到室温后,器件直流特性除欧姆接触电阻改善外,其他都得到了恢复;微波测试表明,器件fT,fmax都随温度升高而下降,180°C时,fT从室温的11.6GHz下降为7.5GHz、fmax从24.6GHz下降为19GHz,通过外推得到350°C时的fT为3.5GHz,fmax为12GHz。证明了AlGaN/GaN HEMT具有良好的热稳定性,适合在高温下进行高频工作。 相似文献