GaInAsSb and InAsSbP photodetectors for mid-infrared wavelengths

Progress on mid-infrared photodetectors fabricated by the liquid phase epitaxial growth of GaInAsSb and InAsSbP on GaSb substrates is reported. Both p/n junction and avalanche photodiode (APD) structures were fabricated. Preliminary results indicate that these devices can have higher detectivity with lower cooling requirements than commercially available detectors in the same wavelength range. Room temperature detectivity (D*) of 1.85 x 10(8) cmHzW(1/2)/W was measured for GaInAsSb detectors, while room-temperature avalanche multiplication gain of 20 was measured on AlGaAsSb/GaInAsSb avalanche photodiodes. Infrared p/n junction detectors made from GaInAsSb and InAsSbP showed cut-off wavelengths of 2.3 mu m and 4.4 mu m respectively.