Self‐organized nanotemplating on misfit dislocation networks investigated by scanning tunneling microscopy

Abstract

Self-ordering growth of nanoarrays on strained metallic interfaces is an attractive option for preparing highly ordered nanotemplates. The great potential of this natural templating approach is that symmetry, feature sizes, and density are predicted to depend on the interfacial stress in these strained layers, which can be adjusted by changing the substrate-thin film composition, temperature, and adlayer coverage. This bottom-up approach of growing nanostructured two-dimensional ordered arrays of clusters on the misfit dislocation networks of strained metallic thin films and surfaces requires a detailed understanding of the nucleation and film-adsorbate interaction processes. Here we show how high resolution, large scale, variable temperature scanning tunneling microscopy imaging can improve our understanding of these self-assembly processes.

Temperature-dependent formation and evolution of the interfacial dislocation network ofAg/Pt(111)

“…Self-organization provides a viable alternative to lithography-like processes, especially if a typical dimension of just a few tens of atoms is desired. The periodicity of such structures can be controlled with subnanometer accuracy using various parameters, such as chemical composition, growth temperature, and the thickness of the film [7].…”

Patterns in strained-layer heteroepitaxy: Beyond the Frenkel-Kontorova model

“…This strain can lead, for example, to the formation of quantum dots via the Stranski-Krastanov growth mode in lattice-mismatched semiconductor systems. [1][2][3][4] In metal heteroepitaxy, [5][6][7][8][9][10][11][12] as well as on some pure metal surfaces, [13][14][15][16] intricate dislocation patterns form as a consequence of interfacial strain. From a fundamental point of view, the patterns that form in strained epitaxial layers are often understood in terms of the classical Frenkel-Kontorova ͑FK͒ model, 17 where the adatom-adatom interaction potential dictates a different lattice constant than the periodic adatom-substrate potential.…”

Self-assembly of methanethiol on the reconstructed Au(111) surface

“…The dimerization mechanism and the bonding geometry are still extensively debated. [7][8][9][10][11][12] For the adsorption of the simplest thiol molecule, CH 3 SH on Au͑111͒ only very recent observational 9,[13][14][15][16] and theoretical 17,18 results are available. While desorption data seem still inconclusive, 9,13 initial scanning tunneling microscopy ͑STM͒ studies show the absence of self-assembly, 13 on-top adsorption at submonolayer ͑ML͒ exposures 14 without affecting the substrate reconstruction.…”