Design and fabrication of a p-i-n photodiode with high responsivity and large alignment tolerances for 40-gb/s applications

This letter demonstrates an evanescently coupled p-i-n photodiode combined with a multimode diluted waveguide using a simple all 2-in InP processing that includes on-wafer mirrors etching and antireflection coating. A high responsivity of 0.81 A/W at 1.55 mum with less than 0.4-dB polarization dependence and a large -1-dB vertical alignment tolerance of 2.70 mum were achieved simultaneously with a bandwidth of 47 GHz. Stable operation for over 1000 h was obtained under bias stress and temperature at 200degC