InAs0.85Sb0.15 infrared photodiodes grown on GaAs and GaAs-coated Si by molecular beam epitaxy

Abstract

We report on the first InAs0.85Sb0.15 infrared photodiodes, grown on GaAs and GaAs-coated Si substrates by molecular beam epitaxy. Transmission electron microscopy images reveal a good structural quality. The electrical characteristics of the photodiodes were analyzed using current-voltage, current-temperature, and capacitance-voltage measurements. The spectral response and detector noise were measured at 77 K, resulting in a peak detectivity at 3.8 µm of 1.5×1011 cm Hz1/2/W for InAs0.85Sb0.15/GaAs and 5.0×1010 cm Hz1/2/W for InAs0.85Sb0.15/GaAs/Si.