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arXiv · 2109.08082

Interface quality in GaSb/AlSb short period superlattices

Md Nazmul Alam·Joseph R. Matson·Patrick Sohr·Joshua D. Caldwell·Stephanie Law
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Abstract

Heterostructures including the members of the 6.1Å 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.

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Md Nazmul Alam, Joseph R. Matson, Patrick Sohr, Joshua D. Caldwell, Stephanie Law. 2021-09-16. Interface quality in GaSb/AlSb short period superlattices. https://doi.org/10.1116/6.0001290

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