InGaAsSb/AlGaAsSb heterojunction photodetectors for wavelength 1.8-2.4 μm grown by LPE

The paper reports on progress in the technology of GaSb-based mid-infrared photodetectors. Photodiode structures were made by LPE and fabricate as mesa-type diodes by RIE etching in CCl/sub 4//H2 plasma. Mesa passivation was carried out in (NH/sub 4/)/sub 2/S water solution. Analysis of PD performance through the measurements of current-voltage and spectral responsivity characteristics have shown that (NH/sub 4/)/sub 2/S passivated photodiode structures are characterized by dark current I/sub d//spl les/13 /spl mu/A at 1 V reverse bias, and quantum efficiency of 0.5/spl divide/0.7 at /spl lambda/=2.3 /spl mu/m and T=300 K.