Si-based photodetectors in optical communication

Si-based photodetectors play key role in the performance of Si-photonic Devices. Design of high performance Si-detectors for optical communication system is a challenging task. Drawbacks arising from low absorption efficiency due to indirect nature of the band-gap in Si, strain in Ge/Si heterointerfaces, etc are to be overcome with suitable structure/design of the detectors. In this paper, a brief review is given on Si-detectors, such as Si-CMOS, SiGe and Ge-on-Si photodetectors including their fabrication techniques, performance trend with some aspects of modeling.