Front End Opto-Electronics for Future Radio Communications

The innovation in the proposed program is the development of a unique process technology that will enable the realization of a high current InP based photodetector with improved current response and reliability performance. The process technology is an epitaxial lift-off (ELO) process where the epitaxial material is completely removed from the substrate. The InP substrate is left intact and can be reused for additional growths, which provides a pathway to a lower cost solution. The ELO process can provide significant improvements in the thermal impedance of the high current photodetector since the substrate is completely eliminated and the remaining photodetector active material can be bonded onto a high thermal conductivity material or other flexible plastic material to provide further integration with a patch antenna. The thermal impedance of the high current photodetector will be the combination of the InGaAs absorber and the thermal sink. The frequency bandwidth of the photodetector will be up to 20 GHz with a goal towards achieving a high output power of 5 W. The wavelength of interest is 1.55 μm, which is lattice matched InGaAs on InP.