The mechanism for the high-quality single-phase growth of MnSi films on Si(111) in the presence of Sb flux

The microstructures of high-quality single-phase MnSi layers grown on Si (1 11) by Mn deposition and reaction with Si in the presence of Sb flux are ch aracterized by Z-contrast imaging. It is found that there is a transition l ayer consisting of two Sb monolayers sandwiching a Mn layer in between the Si substrate and the single-phase MnSi film. This Sb-Mn-Sb sandwich layer e ffectively prevents deposited Mn atoms from direct reaction with Si atoms i n the substrate to form Mn silicides. This explains why high-quality single -phase MnSi layers can be grown with remarkably smooth interface on Si (111 ) substrates. (C) 1999 American Institute of Physics. [S0003-6951(99)01645- 9].