Optical characterization of AlxGa1-xSb/GaSb epitaxial layers

S. Di Lernia, M. Geddo, G. Guizzetti, M. Patrini, A. Bosacchi, S. Franchi, R. Magnanini

Research output: Contribution to journalConference article

4 Citations (Scopus)


Spectroscopic ellipsometry from 1.4 to 5 eV was used to systematically characterize epitaxial heterostructures AlxGa1-xSb/GaSb for different x concentrations (x≤0.5). The structures were grown by MBE at temperatures and beam equivalent pressure ratios which optimize their low-temperature photoluminescence properties. Complex dielectric functions qq(ω) of AlxGa1-xSb versus x were derived, for the first time, from the ellipsometric spectra after mathematically removing the oxide overlayer effects. The qq(ω) spectra were analyzed with their second energy-derivatives in term of standard analytical lineshapes: in particular the E1, E1+△1 and E2 critical point energies, broadening and amplitude parameters were derived as a function of x. On this basis we verified that the energy-shift model is appropriate to interpolate qq(ω) for any x≤0.5, thus allowing a nondestructive optical diagnostic of layer thickness and composition of epitaxial heterostructures based on AlxGa1-xSb.

Original languageEnglish
Pages (from-to)389-394
Number of pages6
JournalMaterials Research Society Symposium - Proceedings
Publication statusPublished - Jan 1 1996
EventProceedings of the 1995 MRS Fall Symposium - Boston, MA, USA
Duration: Nov 27 1995Nov 30 1995


ASJC Scopus subject areas

  • Materials Science(all)
  • Condensed Matter Physics
  • Mechanics of Materials
  • Mechanical Engineering

Cite this

Di Lernia, S., Geddo, M., Guizzetti, G., Patrini, M., Bosacchi, A., Franchi, S., & Magnanini, R. (1996). Optical characterization of AlxGa1-xSb/GaSb epitaxial layers. Materials Research Society Symposium - Proceedings, 406, 389-394.