High-responsivity InGaAs/InP photodetectors integrated on silicon-on-insulator waveguide circuits

This paper presents a high responsivity InGaAs / InP PIN photodetector bonded on silicon-on-insulator (SOI) waveguide circuit with a Si waveguide width of 2000 nm. Divinyltetramethyldisiloxane-benzocyclobutene (DVS-BCB) is used to integrate the InGaAs/InP film epitaxial layers onto the silicon waveguide wafer. A grating coupler is adopted to couple light from the fiber to the Si waveguide. Light in the Si photonic waveguide is evanescently coupled into the InP ridge waveguide and can finally be absorbed in the absorption layer. The simulation results show that the detection efficiency can reach 95%. The measured detector responsivity is 0.87 A/W (excluding the coupling loss between the fiber and the grating coupler and the silicon propagation loss) at a wavelength of 1550nm and a bias voltage of -3V.