Kinetically Limited Molecular Beam Epitaxy of BxGa1–xAs Alloys
journal contributionposted on 28.09.2021, 18:03 by Kyle M. McNicholas, Rasha H. El-Jaroudi, Seth R. Bank
The small lattice constants of the boron pnictides present exciting new opportunities for strain engineering and lattice-matching of III–V semiconductor heterostructures. However, the challenging synthesis of boron-containing III–V alloys has limited the achievable B concentrations to only dilute amounts, hindering both the ultimate application of these materials and experimental investigations of their electronic and optical properties. Using BxGa1–xAs on GaAs and GaP substrates as prototype, we demonstrate a highly kinetically limited molecular beam epitaxy growth regime capable of achieving high substitutional incorporation of boron. By combining the effects of low growth temperature and surfactant-mediated epitaxy with the high boron fluxes accessible with electron-beam evaporation, we achieved substitutional boron incorporation up to a 15% mole fraction, nearly double that of previous reports.