Optical Characterization of Indium Arsenide Antimonide Semiconductors Grown by Molecular Beam Epitaxy
Abstract
The material parameters and crystalline quality of undoped, MBE-grown InAs(1-x)Sb(x) nearly lattice-matched to (100) GaSb (-0.617% less than or equal delta a/a less than or equal +0.708%) similar to material used for mid-infrared semiconductor lasers were determined by optical characterization. Absorption measurements at temperatures between 6-295 K determined the energy gap and wavelength-dependent absorption coefficient for each sample. The compositional dependence of the energy gap was anomalous when compared to previously reported data, suggesting phase separation existed in the material. The samples were also studied by temperature- and excitation-dependent photoluminescence (PL), which, for the majority of cases, showed only a single band-edge peak, identified by comparison with the absorption data. PL linewidths as narrow as 4.3 meV and LO-phonon replicas indicated high material quality, but the shift of the PL peak to higher energies with increased excitation was greater than expected from band filling alone, and underscored the likelihood of phase separation. Extrinsic PL peaks were also observed from one undoped sample, and identified a F-B transition at 4-7 meV and a DAP transition at 10-14 meV below the band edge. Characterization of InAs(1-x)Sb(x):Be identified the Be acceptor energy as >30 meV above the valence band. jg p263
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 01, 1995
- Accession Number
- ADA305925
Entities
People
- Michael A Marciniak
Organizations
- Air Force Institute of Technology