Long wavelength In/sub 0.53/Ga/sub 0.47/As photodetectors on GaAs with a thin super lattice buffer

In/sub 0.53/Ga/sub 0.47/As-based, high speed long wavelength photodetectors have been demonstrated on GaAs substrates with a thin In/sub 0.52/Al/sub 0.48/As/AlAs super lattice buffer of 500 /spl Aring/. The photodetector epitaxial material was grown selectively by solid-source Molecular Beam Epitaxy and fabricated by conventional GaAs MMIC processing. Photoresponsivity of over 0.3 A/W has been achieved for strain relaxed In/sub 0.53/Ga/sub 0.47/As photodetectors fabricated on GaAs substrates, with frequency responses measured up to 50 GHz. The successful demonstration of long wavelength photodetectors with strain-relaxed In/sub 0.53/Ga/sub 0.47/As on GaAs substrates, allows long wavelength optoelectronics or OEICs to take full advantages of the well established GaAs MMIC technology. >