OPTICAL CONTROL OF 14 GHZ MMIC OSCILLATORS BASED ON INALAS INGAAS HBTS WITH MONOLITHICALLY INTEGRATED OPTICAL WAVE-GUIDES/

An In(0.52)AI(0.48)As/In0.53Ga0.47As heterojunction bipolar transistor (HBT) with an novel integrated optical waveguide for light input has been developed. Detailed modeling is used to validate the design and s imulate the coupling of light from the waveguide into the device. Fabr icated waveguide-HBT devices exhibited cutoff frequencies of f(T) = 32 GHz and f(max) = 48 GHz with 56% of the guided light being converted to photocurrent. Fabricated MMIC oscillators operating at 13.9 GHz exh ibited direct optical controllability in the form of optical tuning an d injection locking, This is the highest reported frequency for direct optical injection locking in an HBT-based oscillator.