Nanoanalytical Characterization of Granular Ag-Fe Films with Giant Magnetoresistance
ABSTRACTDedicated scanning transmission electron microscopy and associated techniques were used to extract microstructural and compositional information about granular Ag-Fe magnetic films produced by sputtering. Nanometer-resolution compositional analysis by energy dispersive X-ray spectroscopy (EDS), showed that Ag-Fe granular films consist of two separate phases. It has been found that nanometer size Fe particles are separated by small as well as large Ag particles. Nanodiffraction patterns showed that a large proportion of small Ag particles have an icosahedral shape and that the Fe particles are highly disordered. The nanostructure of the Ag-Fe system and its relation to the giant magnetoresistance of granular films are discussed.