IEEE Transactions on Electron Devices · 1988 · 155 citations · 6 references
SemiconductorsSemiconductor TechnologyElectrical EngineeringEngineeringPhysicsGamma -ValleyElectronic EngineeringApplied PhysicsCondensed Matter PhysicsQuantum MaterialsPossible Near-ballistic CollectionGamma -Valley FeatureElectron TransportModified Collector StructureCategoryiii-v SemiconductorSemiconductor DeviceAlgaas/gaas Hbt
An AlGaAs/GaAs heterojunction bipolar transistor (HBT) structure with an n-p/sup +//sub 1/-i-p/sup +//sub 2/-n/sup +/ doping profile that enables electron collection in the Gamma -valley of GaAs is presented. In fabricated HBTs operating at low collector current density, f/sub T/ reaches its peak value when the potential variation in the i collector layer is around 0.4 V, which indicates that the electron transport is dominated by the Gamma -valley feature in GaAs. A high f/sub T/ value of 105 GHz obtained at a collector current density of 5*10/sup 4/ A/cm/sup 2/ also demonstrates the significance of the proposed near-ballistic collection structure.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
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