Epitaxial Integration of III–V Membrane Photodetectors With Lateral p–i–n Junctions on the Silicon‐On‐Insulator Waveguide Platform

ABSTRACT Membrane III‐V integration has shown great promise for advancing silicon (Si) photonics. In this work, we present lateral p–i–n InP/InGaAs membrane photodetectors (PDs) epitaxially grown on Si in a vertical configuration that mirrors the geometry used in heterogeneous bonding. The membrane PDs are realized in a single epitaxial step via in‐plane, in situ doping. The devices show sub‐200 nA dark current (10 µm length), a small‐signal 3‐dB bandwidth of 24 GHz, and clear non‐return‐to‐zero on–off keying (NRZ‐OOK) eye diagrams at 50 Gb/s, with eyes still measurable at 60 Gb/s. By reproducing the bonded vertical III–V/Si stack by epitaxy, the approach demonstrated here for PDs can also be extended to future hybrid Si‐cavity device implementations, such as hybrid III–V/Si lasers, within a monolithic epitaxial III–V/Si platform.