| AVS 60th International Symposium and Exhibition | |
| Surface Science | Monday Sessions |
| Session SS+AS+NS-MoM |
| Session: | Nanostructures: Growth & Characterization |
| Presenter: | F. Wiame, Chimie ParisTech, France |
| Authors: | F. Wiame, Chimie ParisTech, France C. Poulain, Chimie ParisTech, France Z. Budinska, Chimie ParisTech, France V. Maurice, Chimie ParisTech, France P. Marcus, Chimie ParisTech, France |
| Correspondent: | Click to Email |
Self-organized nanostructured surfaces have been the object of much interest in recent years due to their potential applications as possible alternative to standard lithography techniques. Kern et al. [1] demonstrate that a submonolayer coverage of oxygen deposited on Cu(110) may form periodic stripes aligned along the [001] direction and that the periodicity of the system depends on the coverage. However, although this method appears very promising for the growth of nanostructured materials, the practical applications are limited due to the relatively small domains of periodicity and size as defined by the Marchenko-Vanderbilt (MV) model [2]. For oxygen coverage θO ranging from 0.1 < θO < 0.4 (the full coverage corresponds to θO = 0.5), the periodicity only varies from 6.5 nm to 11 nm and the oxide band width from 2 nm to 9 nm. We will show that these ranges can be significantly increased by the co-adsorption of small amounts of sulphur at the surface.
The new preparation method presented here, which consists in the partial coverage of the surface by sulphur before annealing of the oxidized surface, enables us to significantly enlarge the domain of accessible periodic structures. Periodicity up to 200 nm and oxide band width up to 30 nm can be reached in a straightforward, reproducible and controlled way. The band width and periodicity dispersions are not modified by the sulphur adsorption. Moreover, while the structure of the O/Cu(110)-(2×1) is fully determined by the surface coverage, our method allows us to define the periodicity independently of the oxygen coverage by adjusting the sulphur amount at the surface. A new model has been proposed in order to take into account the effect of the sulphur on the elastic constant of the system. This model allows a reinterpretation of results from the literature [3].
This new system may be used as a template for the growth of nanostructures as well as more fundamental purposes. Indeed, the use of such a versatile structure should enable to gain information e.g. on the elastic and electrostatic properties that are responsible for the nanostructuration of the surface or on the effect of quantum confinement by quasi-one-dimensional structure and how it is influenced by structural modification at the nanometer scale. Moreover, it may be seen as an ideal playground to test the change in the reactivity of a surface as a function of its structure.
[1] K. Kern, H. Niehus, A. Schatz, P. Zeppenfeld, J. Goerge, G. Comsa, Phys. Rev. Lett. 67, 855 (1991).
[2] V. I. Marchenko, JETP Lett 55, 73 (1992) ; D. Vanderbilt, Surf. Sci. 268, L300 (1992).
[3] K Bobrov, L. Guillemot, Surf. Sci. 604, 1894 (2010).