  We demonstrate single crystal growth of wafer-scale hexagonal boron nitride
(hBN), an insulating atomic thin monolayer, on high-symmetry index surface
plane Cu(111). The unidirectional epitaxial growth is guaranteed by large
binding energy difference, ~0.23 eV, between A- and B-steps edges on Cu(111)
docking with B6N7 clusters, confirmed by density functional theory
calculations.
