Structural, optical and electrical characterizations of midwave infrared Ga-Free Type-II InAs/InAsSb superlattice barrier photodetector

Abstract

In this paper, a full set of structural, optical and electrical characterizations performed on midwave infrared barrier detectors based on a Ga-free InAs/InAsSb type-II superlattice, grown by molecular beam epitaxy (MBE) on a GaSb substrate, are reported and analyzed. a Minority carrier lifetime value equal to 1 μs at 80 K, carried out on dedicated structure showing photoluminescence peak position at 4.9 μm, is extracted from a time resolved photoluminescence measurement. Dark current density as low as 3.2 × 10-5 A/cm2 at 150 K is reported on the corresponding device exhibiting a 50% cut-off wavelength around 5 μm. A performance analysis through normalized spectral response and dark current density-voltage characteristics was performed to determine both the operating bias and the different dark current regimes.