The microstructure of Bi2Se3 topological-insulator thin films grown by molecular beam epitaxy on InP(111)A and InP(111)B substrates that have different surface roughnesses has been studied in detail using X-ray diffraction, X-ray reflectivity, atomic force microscopy and probe-corrected scanning transmission electron microscopy. The use of a rough Fe-doped InP(111)B substrate results in complete suppression of twin formation in the Bi2Se3 thin films and a perfect interface between the films and their substrates. The only type of structural defects that persist in the "twin-free" films is an antiphase domain boundary, which is associated with variations in substrate height. It is also shown that the substrate surface termination determines which family of twin domains dominates.
@article{arxiv.1503.06498,
title = {Suppressing twin formation in Bi2Se3 thin films},
author = {N. V. Tarakina and S. Schreyeck and M. Luysberg and S. Grauer and C. Schumacher and G. Karczewski and K. Brunner and C. Gould and H. Buhmann and R. E. Dunin-Borkowski and L. W. Molenkamp},
journal= {arXiv preprint arXiv:1503.06498},
year = {2015}
}