Invited Paper SS1-ThA6
Epitaxial Thin Films and Multilayers: Growth Mode, Microstructure and Physical Property Correlations

Thursday, November 12, 2009, 3:40 pm, Room M

The nucleation and growth mode of thin films determines their microstructure and also many of their physical properties, as for example the magnetic anisotropy in the case of epitaxial magnetic thin films. It is also possible to make artificial multilayers via deposition of subsequent layers of different materials and the microstructure and morphology of the intervening layers and interfaces determines many of the final structure properties.

Artificial metallic superlattices are multilayered thin films prepared by alternately depositing two or more elements epitaxially using ultra-high vacuum deposition or sputtering techniques. The concept of the superlattice was originally developed by physicists Leo Esaki and Raphael Tsu, who were both working at the IBM T. J. Watson Research Center in the 1960s.

Since then a wide spectrum of elements and compounds have been found suitable for deposition into multilayers and superlattice structures. The range of properties displayed by the resulting structures is greatly dependent upon the properties of both individual lattices as well as the interaction between them. For example, multilayers composed of magnetic and non-magnetic materials behave differently than the bulk materials and demonstrate a multiplicity of couplings between the magnetic layers. These couplings can be manipulated by choosing different layer materials and modifying their thicknesses. In fact the Giant Magneto Resistance (GMR) effect was found through such combinations and its discovery led to a Nobel Price in Physics.

In this talk I will present our studies on nucleation and growth of metallic and magnetic layers and the correlation observed between their microstructure and some of their unique physical properties.