At temperatures above ~ 470K, BeO grows epitaxially on the Be{0001} surface, as evidenced by the appearance of the p(1 x 1) low-energy electron diffraction pattern of BeO{0001}. When the oxide grows to thicknesses of the order of 6 or 7 monolayers, the low-energy electron diffraction pattern changes to p(2 x 2)-BeO, which implies the occurrence of a surface reconstruction. This reconstruction was believed to be due to the ordering of a surface ionic charge with total charge equal to ¼ of the net charge per (00•1) atomic plane in BeO. The presence of this surface charge could be explained by considering the electrostatic stability of a wurtzite crystal, such as BeO, growing in the <00•1> direction.

Surface Reconstruction of BeO{0001} during Be Oxidation. D.E.Fowler, J.M.Blakely: Surface Science, 1984, 148[2-3], 283-91