InAs/GaSb superlattice based long-wavelength infrared detectors: Growth, processing, and characterization

We report growth, processing, and characterization of antimonide superlattice long-wavelength infrared photodetectors based on the complementary barrier infrared detector (CBIRD) design. We used photoluminescence measurements for evaluating detector material and studied the influence of the material quality on the intensity of the photoluminescence. We performed direct noise measurements of the superlattice detectors and demonstrated that while intrinsic 1/f noise is absent in superlattice heterodiode, side-wall leakage current can become a source of strong frequency-dependent noise. We developed an effective dry etching process for these complex antimonide-based superlattices that enabled us to fabricate single pixel devices as well as large format focal plane arrays.

Research highlights
► Photoluminescence measurements were used to evaluate the detector material quality.
► Direct noise measurements of the superlattice detectors were performed.
► It was shown that intrinsic 1/f noise is absent in superlattice heterodiodes.
► Side-wall leakage current was found to be a source of strong frequency-dependent noise.
► An effective dry etching process for complex antimonide-based superlattices was developed.