Dark Current Analysis of Vertical p-i-n Photodetectors on a Germanium-on-Insulator Platform

Dark current of vertical p-i-n photodetectors on a germanium-on-insulator platform was analyzed. The activation energy was found to be from 0.15 to 0.36 eV under reserve bias. The dark current generation was interpreted by Shockley-Read-Hall and trap-assisted-tunneling effects. This work provides the interpretation on germanium-on-insulator photodetectors and suggests the alternative to suppress the dark current generation for Si-based Ge photodetectors.