Monolithic GaInAs/InP photodetector arrays for high-density wavelength division multiplexing (HDWDM) applications

Monolithic arrays of interdigitated GaInAs/InP photodetectors have been fabricated for high density wavelength division multiplexing (HDWDM) applications. The detectors typically exhibit a reverse leakage current of 400 nA, capacitance of less than 70 fF and a responsivity of 0.5 A/W at −5 V bias. An optical crosstalk of −33.4 dB has been measured between adjacent detectors in an experimental grating demultiplexer system. Preliminary electrical crosstalk measurements in the frequency range of 1–500 MHz indicate signal isolation of the order of 46 dB.