Fast Ge-on-Si Photodetectors for the Near Infrared

We report on the state of the art of near infrared photodetectors based on germanium on silicon. After a brief review on material and devices, we describe our approach to the fabrication of fast Ge/Si p-i-n detectors based on a simple process with reduced thermal budget for compatibility with standard silicon technology. The diodes, fabricated by chemical vapor deposition at 600oC, exhibit responsivities of 0.4 and 0.2A/W at 1.3μm and 1.55μm, respectively, and operation at 10Gbit/s.