Dark current filtering in unipolar barrier infrared detectors

Control of dark current mechanisms is essential to improving the performance of infrared photodetectors and many other electronic devices. Unipolar barriers can readily be applied to practically and efficiently filter out multiple dark current components exhibited by infrared photodetectors. Via careful placement of unipolar barriers in a standard photodetector architecture, effective suppression of dark currents due to surface leakage, direct band-to-band tunneling, trap-assisted tunneling, and Shockley-Read-Hall generation is demonstrated. We present unipolar barrier photodiodes exhibiting six orders of magnitude improvement in R(o)A and near Auger-limited device performance. (C) 2011 American Institute of Physics. [doi:10.1063/1.3643515]