Initial stage of Schottky barrier formation of ferromagnetic MnSb 0001/films on GaAs 111/B

We have, for the first time, observed the interface chemistry and Schottky barrier formation at the very initial stage of heteroepitaxial growth of ferromagnetic MnSb 0001.films on GaAs 111.B substrates by means of synchrotron radiation photoelectron spectroscopy. We also successfully correlated layer-by-layer growth and Schottky barrier height SBH.with the Ga surface segregation phenomenon, which is a kind of ‘surfactant epitaxy’. From the As 3d core-level shift due to MnSb growth, the SBH was determined to be 0.93 eV. This can be explained by the defect model based on AsGa antisite defects probably generated by the remaining As atoms at the MnSbrGaAs interface. Observation, using cross-sectional transmission electron microscopy, reveals that a good-quality MnSb 0001.film can be grown on MnSb 111.B with an almost abrupt interface. q1998 Elsevier Science B.V. All rights reserved.