Waveguide-integrated PIN photodiode on InP

An InGaAs PIN photodiode was vertically integrated with an inverted optical rib waveguide in InGaAsP. Guided light was transferred to and absorbed by the photodiode at a rate of 0.07 dB/ mu m. For detectors with sufficient length (>300 mu m) a responsivity of 0.81 A/W was achieved at 1.3 mu m wavelength.