QUASIDENDRITIC GROWTH OF CO-INDUCED BY LOCALIZED RECONSTRUCTION OF PT(111)

Co deposited on Pt(111) can form a surprising structure one monolayer high, having threefold symmetric dendritic islands 3-5 nm wide and up to 250 nm long. This new growth mode for anisotropic, ramified structures; is due to a Co-induced localized reconstruction of the Pt(111) surface. The driving force of this reconstruction is attributed to the strain induced by the growth of Co islands at substrate temperatures above 400 K. Locally reconstructed areas act as templates for the further growth of Co islands. Thus the origin of the anisotropy characterizing the Co structure is intimately connected with its growth. This mutual relationship inhibits the side branching characteristics of normal dendritic growth.