Mesa-type InGaAs pin PDs with InP-Passivation Structure Monolithically Integrated with Resistors and Capacitors with Large Capacitance

We have successfully fabricated mesa-type InGaAs pin PDs with InP-passivation structure monolithically integrated with resistors and capacitors. As for the PD characteristics, the capacitance of 0.19 pF and the dark current of 0.2 nA at a reverse bias voltage of 5 V are obtained. By using the MIM/MIS stacked structure in the capacitors, a large capacitance of 91 pF is obtained on a chip area of 440 mum². Although the capacitor is very large, it shows a good reliability and the estimated life time is 60 years at a bias voltage of 10 V and an ambient temperature of 125degC. The results promise the cost reduction and miniaturization of modules and systems for fiber optic communications.