Compositional Control of the Mixed Anion Alloys in Gallium-Free InAs/InAsSb Superlattice Materials for Infrared Sensing (Postprint)
Abstract
Gallium (Ga)-free InAs/InAsSb superlattices (SLs) are being actively explored for infrared detector applications due to the long minority carrier lifetimes observed in this material system. However, compositional and dimensional changes through antimony (Sb) segregation during InAsSb growth can significantly alter the detector properties from the original design. At the same time, precise compositional control of this mixed-anion alloy system is the most challenging aspect of Ga-free SL growth. In this study, the authors establish epitaxial conditions that can minimize Sb surface segregation during growth in order to achieve high-quality InAs/InAsSb SL materials. A nominal SL structure of 77 InAs/35 InAs0.7Sb0.3 that is tailored for an approximately six-micron response at 150 K was used to optimize the epitaxial parameters. Since the growth of mixed-anion alloys is complicated by the potential reaction of As2 with Sb surfaces, the authors varied the deposition temperature (Tg) under a variety of Asx flux conditions in order to control the As2 surface reaction on a Sb surface.
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 28, 2015
- Accession Number
- AD1027822
Entities
People
- Frank Szmulowicz
- G. J. Brown
- H. J. Haugan
- Joseph Peoples
- K. Mahalingam
- S. L. Bowers
Organizations
- Air Force Research Laboratory