Si-based photodetectors are currently studied for providing cheap solution to long haul and short distance communication and optical interconnects. Tensile strained Ge layers grown with suitable barriers show direct gap type I band alignment. We have worked on resonant cavity enhanced (RCE) photodetectors using Ge/SiGe type I structure. Performance of photodetectors using strong Quntum Confined Stark Effect, and Franz-Keldysh Effect and properties related to photodetection paper.