Silicon hybrid photodetector based on die-to-die bonding

摘要

A silicon hybrid photodetector was demonstrated based on die-to-die bonding technology. The vertically incident InGaAs/InP photodetector die was integrated on silicon-on-insulator (SOI) die by using divinyldisiloxane benzocyclobutene (DVS-BCB) as adhesive layer. A grating coupler was fabricated on SOI substrate to diffract the light out of the SOI waveguide into the detector. The measured coupling efficiency output at 1550 nm for the TE mode reached to 39.8%, which is equal to 8.2 dB fiber-to-fiber loss. After integrating, when the thickness of the BCB bonding layer was 380 nm, the optical loss reached to 13.8 dB with 30x30 urn2 device. The measured dark current, bandwidth and responsivity of the hybrid InGaAs/InP photodetector with light absorbing mesa of 10x10 urn2 were 37.7 nA, 30.9 GHz and 0.48 AAV respectively at -3 V DC bias.