Digital alloy growth in mixed As/Sb heterostructures

• Published in: Journal of crystal growth 2003-04, Vol.251 (1), p.515-520
• Main Authors: Kaspi, Ron, Donati, Giovanni P.
• Format: Article
• Language: English
• Subjects: A3. InAs/GaSb superlattice; B1. Digital alloying; B1. Mixed As/Sb alloys; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; Exact sciences and technology; Low-dimensional structures (superlattices, quantum well structures, multilayers): structure, and nonelectronic properties; Materials science; Methods of deposition of films and coatings; film growth and epitaxy; Molecular, atomic, ion, and chemical beam epitaxy; Optical properties and condensed-matter spectroscopy and other interactions of matter with particles and radiation; Optical properties of low-dimensional, mesoscopic, and nanoscale materials and structures; Physics; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties)
• ISSN: 0022-0248; 1873-5002
• DOI: 10.1016/S0022-0248(02)02185-1

We consider the digital alloy growth of mixed As/Sb layers by molecular beam epitaxy. Using the (InAs) n (GaSb) 3 n superlattice as an example, we determine an acceptable upper limit to the modulation period before significant deviation from the In 0.25Ga 0.75As 0.25Sb 0.75 bandgap occurs. We then consider the digital alloy growth of In 0.2Ga 0.8As y Sb 1− y layers on GaSb, and find that the digital alloying technique provides protection against compositional drift in the growth direction due to reduced sensitivity to variations in arsenic-flux and substrate temperature.