Progress toward competitive Ge/Si photodetectors

Abstract

Research and development on silicon-based optoelectronic devices is increasing as the need for integrated optical devices is becoming more apparent. One component which has seen rapid performance improvement over the last five years has been a Ge-on-Si photodetector which can operate between 850 and 1600 nm with high quantum efficiencies and bandwidths. We have reported on three types of these detectors; normal incident illuminated p-i-n detectors, waveguide p-i-n detectors, and avalanche photodetectors (APDs). The former has achieved -14.5 dBm sensitivity at 10 Gb/s and 850 nm, which is comparable to similarly commercially packaged GaAs devices. Waveguide photodetectors have achieved bandwidths of approximately 30 GHz at 1550 nm with internal quantum efficiencies of 90%. Normal incident avalanche photodetectors operating at 1310 nm have achieved a primary responsivity of 0.54 A/W with a 3-dB bandwidth of 9GHz at a gain of 17.