Résumé
The Ga-free InAs/InAsSb type 2 superlattice (T2SL) is now considered as a suitable quantum structure for a high-performance photodetector operating at 150 K in the midwave infrared (MWIR) spectral region. In this chapter, we describe how to select a strain-balanced MWIR Ga-free T2SL structure on GaSb substrate and the molecular beam epitaxy (MBE) growth conditions, through structural and optical characterizations, to achieve a high-quality structure in terms of both absorption coefficient and minority carrier lifetime. A focus is made on transmission electron microscopy (TEM) measurements which reveal a strong segregation of antimony (Sb) at T2SL interfaces, thus disrupting the initial schematic representation of abrupt quantum potentials.