HIGH QUANTUM EFFICIENCY AND NARROW ABSORPTION BANDWIDTH OF THE WAFER-FUSED RESONANT IN0.53GA0.47AS PHOTODETECTORS

We demonstrate greater than 90% quantum efficiency in an In0.53Ga0.47A s photodetector with a thin (900 angstrom) absorbing layer. This was a chieved by inserting the In0.53Ga0.47As/InP epitaxial layer into a mic rocavity composed of a GaAs/AlAs quarter-wavelength stack (QWS) and a Si/SiO2 dielectric mirror. The 900-angstrom-thick In0.53Ga0.47As layer was wafer fused to a GaAs/AlAs mirror, having nearly 100% power refle ctivity. A Si/SiO2 dielectric mirror was subsequently deposited onto t he wafer-fused photodiode to form an asymmetric Fabry-Perot cavity. Th e external quantum efficiency and absorption bandwidth for the wafer-f used RCE photodiodes were measured to be 94 +/- 3% and 14 nm, respecti vely. To our knowledge, these wafer-fused RCE photodetectors have the highest external quantum efficiency and narrowest absorption bandwidth ever reported on the long-wavelength resonant-cavity-enhanced photode tectors.