Initial growth mode of ultrathin Ag films on an Al(111) surface - art. no.085414

The initial growth mode of ultrathin Ag films grown on an Al(111) surface w as studied using Auger electron spectroscopy, low-energy electron diffracti on (LEED) and x-ray photoelectron spectroscopy. Although Al and Ag have the same fcc bulk structure with nearly the same lattice parameters and a simi lar homoepitaxial growth mode, the initial growth mode of Ag on an Al(111) surface showed quite an unexpected behavior. As silver was deposited on an Al(111) surface at room temperature, the intensities of LEED spots diminish ed exponentially up to about 2 monolayer (ML), and the LEED pattern complet ely disappeared between 2 to 4 ML coverage. After 4 ML thick deposition, (1 x1) LEED pattern started to reappear. To explain these experimental results , we propose a growth model of Ag film on the Al(111) surface that incorpor ates stacking faults induced by an interface alloy formation as observed in our spectroscopic work.