1/f Noise and Dark Current Correlation in Midwave InAs/GaSb Type-II Superlattice IR Detectors

Abstract

Herein, results from noise and dark current density studies on InAs/GaSb type-II superlattice IR detectors are presented. The activation energy of the dark current density is used to identify the dominating dark current mechanisms (generation–recombination (GR), tunneling, or diffusion dark current) as a function of temperature and bias. The bias evolution of the power spectral density (PSD) is measured in dark conditions for several temperatures. At the operating bias of the detectors, the arrays show a white noise–dominated spectrum up to 100 K with a minor 1/f contribution (corner frequency around 10 Hz), while for higher temperatures the spectra are 1/f dominated. The 1/f noise component is compared to the dominating dark current mechanism in the same temperature and bias regimes. A strong correlation between the 1/f noise component and the dominating dark current (I) is found, with the PSD proportional to I for tunneling currents and I2 for GR and diffusion currents. Very low noise coefficients of αGR = 4.8 × 10−9 Hz−1, αdiff = 1.9 × 10−10 Hz−1, and αtun = 2.1 × 10−16 A Hz−1 are observed for these detectors.