cicCartuja Centro de Investigaciones Científicas de la cartuja
Título: Nanostructures – Preparation and Applications
Conferenciante: Prof. Bernd Rauschenbach del Leibniz Institute of Surface Modification (IOM), Leipzig, Germany
Fecha: jueves 18 de enero de 2018
Horario: 11:30 h
Lugar: Salón de Grados cicCartuja 2
Abstract: Nanostructures with a three dimensional tailored shapes are promising candidates for a variety of applications. Sputter technology, oblique angle deposition and glancing angle deposition are sophisticated methods to create nanostructures with custom-made structure geometries. Selected results of these three methods to prepare nano- and micro-structures are presented.
(1.) Low-energy ion beam sputtering, i.e. the removal of atoms from a surface due to the impact of energetic ions or atoms, is an inherent part of numerous surface processing techniques. Two prominent examples are the spontaneous formation of well-ordered ripple or dot pattern and the realization of experimental conditions where surface relaxation dominates and smooth surfaces are emerging. Both special cases are of high interest for many potential applications in nanotechnology.
(2.) Combining ion sputter deposition or electron beam evaporation and oblique angle deposition represents an elegant and powerful technique to sculpture manifold surface morphologies on the nanometer scale. Besides different examples of films prepared by oblique deposition a model describing the growth of nanostructures for the full angle of incidence range (0° - 90°) is proposed. Predictions of this model for tilt angles and porosities are shown and compared to an off-lattice computer simulation as well as to deposited films of different materials.
(3.) A constant or periodically interrupted substrate rotation during deposition is used to tailor structures like chevrons, posts, circular and quadratic spirals or zig-zags. The growth of these nanostructures on non-patterned substrates, regularly arranged Si nanostructures and the growth conditions are discussed. Regular arrays of nanostructures are grown on several substrates by patterning with Au dots using self-assembled mono- and double layers of polystyrene nano-spheres as evaporation mask or electron beam lithography. Finally, examples are given for the applications of sculptured thin films in the field of chemical and biosensors.
