High operating temperature 320x256 middle-wavelength infrared focal plane array imaging based on an InAs/InGaAs/InAlAs/InP quantum dot infrared photodetector

This letter reports a 320x256 middle-wavelength infrared focal plane array operating at temperatures up to 200 K based on an InAs quantum dot/InGaAs quantum well/InAlAs barrier detector grown on InP substrate by low pressure metal organic chemical vapor deposition. The device's low dark current density and the persistence of the photocurrent up to room temperature enabled the high temperature imaging. The focal plane array had a peak detection wavelength of 4 mu m, a responsivity of 34 mA/W, a conversion efficiency of 1.1%, and a noise equivalent temperature difference of 344 mK at an operating temperature of 120 K. (C) 2007 American Institute of Physics.