Short wavelength infrared pBn GaSb/AlAsSb/InPSb photodetector

A pBn GaSb/AlAsSb/InPSb detector, with a photoluminescence peak at 2.9 µm, for the short wave infrared range was fabricated and characterized. At −0.5 V the dark current at 300 and 200 K was 1.5 × 10−1 and 3.5 × 10−3 A/cm2 and the detectivity was above 109 and 1010 cm-Hz1/2/Watt respectively. The quantum efficiency at λ = 2.2 µm and −0.5 V, for 300 K and 200 K, is 39% and 48% respectively. A simulation implies that a potential barrier for generated holes degrades the optical performances at zero bias. Electrical characteristics at different temperatures and details of the process flow are also described.