Uncooled InAsSb Photoconductors with Long Wavelength

High-sensitivity uncooled InAsSb photoconductors with long wavelength were successfully fabricated. The detectors are based on InAsSb epilayers with the thickness of 100 µm grown on InAs substrates by melt epitaxy (ME). Si optical lenses were set on the photoconductors without any antireflective coatings. At room temperature, the peak detectivity Dλp* (6.5 µm, 1200) reaches 5.3 ×109 cm Hz1/2 W-1 for InAsSb immersion photoconductors. The detectivity D* at the wavelength of 8 µm is 1.5 ×108 cm Hz1/2 W-1, and that at 9 µm is 1.0 ×107 cm Hz1/2 W-1. The excellent performance of the detectors indicates the potential applications for infrared (IR) detection and imaging at room temperature.