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(Co, Zn)O compound has been obtained by a non-expensive synthesis route. ZnTe thin films were obtained by isothermal close space sublimation on the Co thin layer previously sputtered on silicon substrates. After the annealing process in humid ambient cobalt atoms diffusion and Zn oxidation were obtained besides partial Te evaporation. The detailed characterization of the samples by using XRD, RBS, AFM, XPS, VSM and MFM techniques point to the formation of room temperature ferromagnetic Co xZn(1− x)O phase ( x<0.15). This ferromagnetic behavior is mainly attributed to Co atoms substituting Zn atoms in the ZnO network. [ABSTRACT FROM AUTHOR]

Systematic study of magnetic nanowire arrays grown in anodic alumina membranes (AAM) has been done by means of Rutherford backscattering spectroscopy (RBS). The AAM used as templates were morphologically characterized by using high resolution scanning electron microscopy (HRSEM), fast Fourier transform (FFT) and atomic force microscopy (AFM). The highly ordered templates with a mean pore diameter size of 30 nanometers, a mean inter-pore spacing of 100 nm and lengths ranging from 4 to 180 microns were obtained through two-steps anodization process, and the Ni and Co nanowire arrays were grown by electrodeposition techniques. The main attention is addressed to Ni nanowire arrays. RBS results allowed us to determine the real depth profile of atomic composition of the obtained nanowire arrays. In addition, the RBS spectra fitting showed that the porosity increased from the top to the bottom of the samples. Two phenomenological models are proposed to understand the apparition of that secondary porosity and a linear relation between the total amount of electrodeposited Ni and the electrodeposition time was obtained. As an example, it is also reported the relation between RBS results and magnetic properties, such as coercive field and remanence/saturation magnetization ratio of the samples. Particularly, for Ni nanowires arrays obtained by using voltage pulses, it is demonstrated that the larger the nanowires, the higher the definition for easy axis parallel to the nanowire length is possible. [ABSTRACT FROM AUTHOR]