LAUSR

Abstract This paper reports on the influence of growth angle on morphology and uniaxial magnetic anisotropy of 60 nm-thick sputter-deposited cobalt films on patterned-Ge substrates (having nanowire-like morphology with extreme regularity) prepared by keV-ion bombardment at room temperature. Morphological studies reveal that grain size in Co films increases with increasing growth angle, albeit lateral spacing among the ridges of conformally grown Co films (under growth angles in the range of 0–70°) on patterned-Ge substrates match quite well with that of a patterned-Ge substrate. While an increase in the Co grain size is expected to cause higher coercive fields, in the presence of magnetic pinning and slopes between ridges and grooves of nanowire-like patterned Co morphology, we observe an inverse trend. In other words, an increase in the grain size in conjunction with respective evolution of microstructures in Co films, at higher growth angles, lead to a decrease in the coercive field. Magnetic force microscopy is employed to probe the out-of-plane domains in ferromagnetic Co films. Tailored design of these novel nanostructured Co layers will be of interest for fabrication of high-density magnetic data storage devices, magneto-transport phenomena, and magneto-plasmonics.