Low-voltage high-speed thin-film-Ge surface PIN photodetectors integrated on Si waveguide

摘要

In this article, we demonstrate the thin-film-Ge surface PIN photodetectors. With thin Ge layer (~120nm including buffer layers), the devices couple well with the incoming Si waveguide and achieve high responsivity due to the surface layout of the highly-doped p++ region. By shrinking the p++ spacing of the device, the device exhibits high speed of ~20 GHz at the bias of -1V.