Epitaxial III-V-on-silicon waveguide butt-coupled photodetectors

Abstract

We report silicon waveguide butt-coupled p-i-n InGaAs photodetectors epitaxially grown on silicon-on-insulator substrates by metalorganic chemical vapor deposition. The InGaAs absorption layer that is lattice-matched to InP is selectively grown on patterned SOI substrates, employing metamorphic growth of GaAs and InP buffer layers. We measure a dark current of 2.5 μA and a responsivity of 0.17 A/W at 1550 nm wavelength upon -1 V bias voltage, with a 20 μm × 20 μm InGaAs photodetector area. This device exhibits a 3 dB bandwidth of 9 GHz upon -4 V bias voltage. We demonstrate an open-eye diagram at 10 Gb/s data rate upon -4 V bias voltage.