Abstract
We design a High efficiency-bandwidth product(EBP) PIN Germanium photodector and use critical coupling theory to analysis our structure . It can lock all incident light in this photodector so significantly enhance Quantum efficiency result in only several hundreds of nanometer thickness but Quantum efficiency can exceed 90%.Because of a very thin depletion region, carrier spend a few transit time, and bandwidth can exceed 50GHz . Some disadvantage like linewidth is too narrow so if light source wavelength shift let Quantum efficiency drop significantly, To overcome this problem, we use anomalous dispersion mirror to compensate cavity total phase and realize flat-top Quantum efficiency.