First-principles study on shape of intrinsic hBN island nucleated during CVD initial growth on Cu(111)

Using the first-principles calculation, the shape of the hexagonal boron nitride (hBN) islands was investigated, with a focus on the edge of the small monolayer hBN islands on Cu(111) and intrinsic nucleation during the CVD initial growth. Several key observations were made. First, desorption does not play a decisive role in shaping the islands. Second, for small islands, there is no chemical potential range where the armchair edge is stable. Third, the bonds between Cu atoms on the surface and N atoms at the edge are strong, whereas the bonds between Cu atoms on the surface and B atoms at the edge are comparatively weaker. Finally, triangular islands with N edge tend to grow more spontaneously than those with B edge because the critical size is smaller for those with N edge across a wide chemical potential range.