Patents Assigned to Fox-Tek
  • Single-waveguide integrated wavelength demux photodetector and method of making it
    Patent number: 6731850
    Abstract: A photodetector has a spatially varying absorption spectrum formed in a monolithic InGaAsP structure whose quantum well active structure has modified effective bandgap properties. A waveguide couples light to the quantum well active structure. The spatially varying absorption spectrum allows wavelength-division demultiplexing. The effective bandgap properties can be modified by rapid thermal annealing to cause the diffusion of defects from one or two InP defect layers into the quantum well active structure.
    Type: Grant
    Filed: November 16, 2001
    Date of Patent: May 4, 2004
    Assignee: Fox-Tek
    Inventor: Edward H. Sargent