Improvement of mid-wavelength InAs/InAsSb nBn infrared detectors performance through interface control

We report our study to optimize the growth of mid-wavelength InAs/InAsSb nBn infrared detectors through interface control method with AlSb/AlAs superlattices as electron barrier. The dark current model was employed to investigate the dominant dark current mechanism at various operating temperatures. We extracted the minority carrier lifetime of InAs/InAsSb material grown by different interface growth methods. Electrical and optical characterizations indicated superior performance of the device grown by migration-enhanced epitaxy (MEE) with a 3 s As and Sb soak time. With −0.3 V applied bias and 150 K operating temperature, the optimal device shown a dark current density of 8.95 × 10⁻⁶ A/cm² and peak specific detectivity of 7.12 × 10¹¹ cm Hz^1/2/W at 3.8 µm.