Ring oscillators with optical and electrical readoutbased on hybridGaAs MQW modulators bonded to 0.8 µm silicon VLSI circuits

Loaded and unloaded ring-oscillator circuits with an electrical and surface-normal 850 nm optical readout are fabricated using a hybrid 0.8 µm silicon-CMOS/GaAs-AlGaAs MQW process. Measurements of the oscillation frequency of these circuits show total capacitance associated with the flip-chip-bonded optical MQW modulators as low as 52 fF.