Surface structures induced by the growth of Cr on Cu(111) at room temperature were studied with scanning tunnelling microscopy. At sub-monolayer Cr coverage, islands and vacancy islands with lateral sizes of about 10nm in length were observed. The islands showed one- or two-monolayer heights with irregular shapes, while vacancy islands have one-monolayer depth and hexagonal shapes with openings. Atomic structures inside and near the vacancy islands were the same as those of bare Cu(111), implying that Cu atoms detach from the vacancy islands and attach to other step edges and islands.

Two-Dimensional Vacancy Islands Induced by the Growth of Cr on Cu(111). J.K.Yoon, G.E.Jung, H.Kim, K.H.Chung, S.J.Kahng: Thin Solid Films, 2010, 519[4], 1375-9