Integrated Guided-Wave Photodiode Using Through-Absorber Quantum-Well-Intermixing

A high-speed, high-saturation power photodiode compatible with a relatively simple monolithic integration process is described. The detector is comprised of an intrinsic bulk absorption layer, an electron drift region, and a field termination layer, and is grown above a main waveguide core comprised of a number of quantum wells, which are used as the active region of a phase modulator. Through-absorber quantum-well-intermixing is used to blue-shift the bandedge of the underlying quantum wells, reducing the optical losses of that material. The detectors demonstrate quantum efficiency, input saturation power, and 3-dB bandwidth of 50 GHz.