Medium-energy ions scattering studies of ultrathin metallic films on the face-centred cubic (111) surface

An experimental investigation of ultrathin metallic films on face centred cubic(111) surfaces using medium energy ion scattering as a primary experimental technique is reported. A suite of custom software written for data-processing, calibration and analysis has also been described. The specific experimental systems investigated are 0.25 ML to 3.89 ML of palladium on copper(111) and 0.23 ML to 3.74 ML of silver on aluminium(111). The Pd CU(111) system was shown to exhibit 42% twinning at 0.25 ML through 4.74 ML. At 0.25 ML coverage it has been shown that the Pd migrates into the top three layers of the substrate. The Pd was shown to be distributed 27% ± 3%, 67% ± 3% and 6% ± 3% in the 1st, 2nd and 3rd layers. The first and second interlayer spacings we also found to contract by 4% and expand by 4% respectively for the 0.25 ML coverage. [Continues.]