Silicon-contacted waveguide integrated Ge/Si avalanche photodiode with 32 GHz bandwidth and multiplication gain > 8

We report a waveguide integrated Ge/Si avalanche photodiode with primary responsivity of 0.78 A/W, multiplication gain >8 and a bandwidth of 32 GHz at −12 V. Wide-open eye diagrams are obtained at 8.5 multiplication gain for 25, 40 and 50 Gbps NRZ-OOK data rates.