Electron effective mass and phonon modes in GaAs incorporating boron and indium

Authors

Tino Hofmann, University of Nebraska - LincolnFollow
Mathias Schubert, University of Nebraska - LincolnFollow
G. Leibiger, Freiberger Compound Materials GmbH, Am Junger Löwe Schacht 5, 09599 Freiberg, Germany
V. Gottschalch, Institute of Inorganic Chemistry, Faculty of Chemistry and Mineralogy, Universität Leipzig, Linnéstraße 3, 04103 Leipzig, Germany

Date of this Version

2007

Comments

Published in APPLIED PHYSICS LETTERS 90, 182110 (2007). Copyright © 2007 American Institute of Physics. Used by permission.

Abstract

The strain-free boron- and indium-containing GaAs compounds are promising candidates for III-V semiconductor solar cell absorber materials with lattice match to GaAs, for which experimental data of the electronic band structure are widely unknown. For nondegenerate, silicon-doped, n-type B_0.03In_0.06Ga_0.91As with band-gap energy of 1.36 eV, determined by near-infrared ellipsometry, a strong increase of the electron effective mass of 44% in B0.03In0.06Ga0.91As compared to In_0.06Ga_0.94As is obtained from far-infrared magneto-optic generalized ellipsometry studies. The authors thereby obtain the vibrational lattice mode behavior. For BAs, an experimentally obscure compound, the curvature of the Г-point conduction band thus extrapolates to the free electron mass.