InAsSb/GaSb heterostructure based mid-wavelength-infrared detector for high temperature operation

The properties of a midinfrared photodetector, based on a lattice matched n-N InAs0.91Sb0.09/GaSb type-II heterostructure, were investigated. The relatively simple two layer structure shows very promising characteristics for sensitive and dual color infrared detection. I-V characteristics and spectral response were measured at the temperature range of 10-300 K. High zero-bias resistance area product R(0)A of 2.5 Omega cm(2) was obtained at room temperature. The measured background limited infrared photodetection temperature was 180 K corresponding to 4.1 mu m cutoff. Shot and Johnson noise limited detectivities corresponding to InAsSb absorption were measured to be 1.3x10(10) and 4.9x10(9) cm Hz(1/2) W-1 at 180 and 300 K, respectively. An enhanced optical response with gain larger than unity was observed below 120 K. Bias tunable dual color detection was demonstrated at all measured temperatures. (c) 2007 American Institute of Physics.