Structural and Magnetic Characterization of Rare Earth and Transition Metal Films Grown on Epitaxial Buffer Films on Semiconductor

Abstract

ABSTRACTStructural and magnetic data are presented and discussed for epitaxial films of rare earth metals ( Dy, Ho, Er) on LaF3 films on the GaAs(TTT) surface and Fe on Ag films on the GaAs(001) surface. Both systems exhibit unusual structural characteristics which influence the magnetic properties of the metal films. In the case of rare earth epitaxy on LaF3 we present evidence for epitaxy across an incommensurate or discommensurate interface. Coherency strain is not transmitted into the metal which behaves much like bulk crystals of the rare earths. In the case of Fe films , tilted epitaxy and long-range coherency strain are confirmed by X-ray diffractometry. Methods of controlling some of these structural effects by modifying the epitaxial structures are presented.