Share Email Print
cover

Proceedings Paper

Molecular Beam Epitaxial Growth Of InAsSb Superlattices For IR Applications
Author(s): L.Ralph Dawson
Format Member Price Non-Member Price
PDF $14.40 $18.00

Paper Abstract

The use of tensile strain parallel to (100) interfaces in InAs xSb1-x strained-layer superlattices (SLSs) is a promising . technique for realizing III-V materials structures with small enough energy gap to achieve cutoff wavelength in excess of 12pm at 77K. These SLS materials have been grown by MBE using Sb2 and As, sources at substrate temperature of 425-450°C on InSb substrates with suitable intervening buffer layers. The entire epitaxial structure (buffer layers plus SLS) is in tension with respect to the thick InSb substrate, leading to extensive cracking of the material when conventional buffer layers are used. The cracking problem has been overcome by the initial growth of a severely mismatched buffer layer directly onto the InSb substrate. The resulting high level of strain induces the nucleation of enough dislocations to relieve much of the strain in the ensuing epitaxial layer, avoiding the accumulation of strain energy sufficient to form cracks. Subsequent grading layers are in compression and cracking does not occur. InAs 1Sb 9/InAs 3Sb7 SLSs grown on such buffers are crack-free and' 3shoc4 substantiai reduction in dislocation density relative to that in the buffer layers. FTIR measurements show substantial absorption at wavelengths beyond the cutoff wavelength for bulk InAsSb alloys.

Paper Details

Date Published: 15 August 1988
PDF: 1 pages
Proc. SPIE 0944, Growth of Compound Semiconductor Structures II, (15 August 1988); doi: 10.1117/12.947371
Show Author Affiliations
L.Ralph Dawson, Sandia National Laboratories (United States)


Published in SPIE Proceedings Vol. 0944:
Growth of Compound Semiconductor Structures II
Anupam Madhukar, Editor(s)

© SPIE. Terms of Use
Back to Top