Short noteImproved performance of InAs0.07Sb0.93 photoconductors operating at room temperature

In this study, the improvement of detectivities D* at the wavelength of 8 and 9 μm of InAs0.07Sb0.93 photoconductors are provided. InAs0.07Sb0.93, InAs0.05Sb0.95 and InAs0.03Sb0.97 thick epilayers were grown on InAs substrates by melt epitaxy (ME). The photoconductors were fabricated based on the epilayers. Ge immersion lenses were set on the devices. At room temperature, the photoresponse wavelength range was 2-10 μm. The peak detectivities Dλp* (6.5 μm, 800) were larger than 1.0 × 109 cm Hz1/2 W−1. The detectivities D* at 8 and 9 μm of InAs0.07Sb0.93 detectors were raised to 5.01 × 108 cm Hz1/2 W−1 and 2.92 × 108 cm Hz1/2 W−1 respectively, which are higher than that of InAs0.05Sb0.95 and InAs0.03Sb0.97 detectors. It benefits from arsenic composition increasing in the epilayers.