IEEE Transactions on Microwave Theory and Techniques · 2003 · 47 citations · 16 references
EngineeringElectrical EngineeringMaterials ScienceMicroelectronicsSemiconductor DevicesSemiconductor MaterialsDevice CharacterizationHigh-frequency Semiconductor DevicesMicrowave Semiconductor DevicesWide Band Gap SemiconductorsWide-bandgap Semiconductor DevicesWide-bandgap SemiconductorsDevice BiasingGallium Nitride (Gan) MaterialsHigh-electron-mobility TransistorsLoad-pull AnalysisMicrowave DevicesPower Added EfficiencyPower OutputSaturated Output Power
Dynamic loadline analysis illustrating the microwave performance limits of state-of-the-art AlGaN/GaN high electron-mobility transistors (HEMTs) under pulsed RF biasing and drive conditions are presented. Calculation of dynamic loadlines concurrent with load-pull measurements show the increase of the device RF knee voltage with increasing drain voltage as the cause of reduced output power-added efficiency (PAE) at high drain biases. In this study, an 8-GHz saturated output power of 14.1 W (9.4 W/mm) is achieved on a 1500 /spl times/ 0.25 /spl times/ /spl mu/m/sup 2/ AlGaN/GaN HEMT at a pulsed drain bias of V/sub D/=40 V. The pulsed-bias conditions considered here preclude device self-heating as a mechanism responsible for the lower than expected output power and decrease in PAE with increasing drain bias. These data suggest electron trapping associated with the surface of the device between the gate and drain as the mechanism that limits the ultimate power, PAE, and linearity of AlGaN/GaN HEMTs.
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Transient electron transport in wurtzite GaN, InN, and AlN
B. E. Foutz, Stephen K. O’Leary, M. S. Shur et al. · Journal of Applied Physics · 1999 · 558 citations
Very-high power density AlGaN/GaN HEMTs
Yifeng Wu, D. Kapolnek, J. P. Ibbetson et al. · IEEE Transactions on Electron Devices · 2001 · 558 citations