Temperature Dependence of Ag Film Roughening during Deposition on Quasicrystal and Approximant Surfaces

The temperature (T) dependence of roughening as assessed by scanning tunneling microscopy is compared for growth of Ag films on an 5-fold icosahedral Al-Pd-Mn quasicrystal surface and on an ξ'-approximant. Growth on the quasicrystal corresponds to a version of the Volmer-Weber growth, but modified by quantum size effects, and also by kinetic smoothening at low T and low coverages (θ). Growth on the approximant corresponds to a version of the Stranski-Krastanov growth modified by kinetic roughening at low T and low θ. For larger θ, i.e., for thicker films, distinct behavior is observed.