Morphology of Pd multilayers on Cu(110)

The growth of Pd films deposited on a Cu(110) single crystal surface and the resulting morphology of the film structure has been followed by STM for deposition at 310 K. For similar to 1 hit films an ordered (2 x 1) surface alloy is formed which is also visible in LEED. The surface morphology is, however, not flat but has roughened step edges, raised islands and smaller trenches. For increased coverages of Pd the growth shifts to the formation of rectangular multilayered Pd islands. Upon annealing, AES shows a preferential segregation of Cu to the surface region that accompanies a flattening of the surface morphology in STM. Annealing thick films (>4 ML) to 603 K produces a surface morphology with larger flat terraces and small islands that have rough, non-crystallographically aligned step edges. With further annealing to 723 K these surfaces also display large-scale 'banding' in the STM images that we attribute to stress relaxation between the CuPd alloy and Cu. (C) 1999 Elsevier Science B.V. All rights reserved.