Heterostructures including the members of the 6.1{\AA} semiconductor family (AlSb, GaSb, and InAs) are used in infrared optoelectronic devices as well as a variety of other applications. Short-period superlattices of these materials are also of interest for creating composite materials with designer infrared dielectric functions. The conditions needed to create sharp InAs/GaSb and InAs/AlSb interfaces are well known, but the AlSb/GaSb interface is much less well-understood. In this article, we test a variety of interventions designed to improve interface sharpness in AlSb/GaSb short-period superlattices. These interventions include substrate temperature, III:Sb flux ratio, and the use of a bismuth surfactant. Superlattices are characterized by high-resolution x-ray diffraction and infrared spectroscopy. We find that AlSb/GaSb short-period superlattices have a wide growth window over which sharp interfaces can be obtained.
Cite
@article{arxiv.2109.08082,
title = {Interface quality in GaSb/AlSb short period superlattices},
author = {Md Nazmul Alam and Joseph R. Matson and Patrick Sohr and Joshua D. Caldwell and Stephanie Law},
journal= {arXiv preprint arXiv:2109.08082},
year = {2021}
}