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[en] In this research Pt thin film deposited on Au substrate by electrodeposition method in various current density (correspond to rate of deposition) to find its effect on layers surface topography. Layers thickness controlled to be 500 nm. The root mean square of roughness (w) and the roughness exponent (a) are determined. The results show that increasing the current density leads to increase both w and a as well. This result also shows the surface height fluctuation increases but height changes rather slowly. Consequently by increasing the current density the film surfaces become rough.

[en] The room-temperature magnetoresistance (MR) and magnetization characteristics were investigated for electrodeposited Ni-Co-Cu(3 nm)/Cu(d_Cu) multilayers with d_Cu=1 and 2 nm as a function of the ratio of Co to Ni in the magnetic layer. The maximum giant magnetoresistance (GMR) was obtained when the Co- and Ni-contents of the magnetic layer were approximately equal for d_Cu=1 nm, whereas a significantly smaller GMR with no systematic dependence on Co-content was observed for d_Cu=2 nm. Concurrent increase of the coercive field (H_c) and the MR peak position (H_p) with Co-content was observed for d_Cu=1 nm up to a Co:Ni ratio of 1:1, beyond which H_p increased faster than H_c, with H_p∼2H_c when the ratio reached ∼4:1. For films containing approximately equal quantities of Co and Ni, the MR vs. H curves could be successfully fitted by a Langevin function. This was interpreted by ascribing the magnetization contribution for magnetic fields above about 2H_c to superparamagnetic (SPM) regions which form due to the electrochemical deposition conditions between the non-magnetic Cu layer and the ferromagnetic (FM) Ni-Co-Cu layer. The formation of such intermixed interfaces is a general phenomenon in electrodeposited multilayers, leading to a strongly reduced antiferromagnetic coupling of the magnetizations of the neighbouring FM layers. In such cases, the observed GMR curves exhibit a typical concave shape and arise due to the slowly saturating SPM behaviour at the intermixed interfaces

[en] :The Boltzmann equation is a semiclassical approach to the calculation of the electrical conductivity. In this work we will first introduce a simple model for calculation of thin film resistivity and show that in an appropriate condition the resistivity of thin films depends on the electron mean free path, so that studying and measurement of thin films resistivity as a function of film thickness would lead to calculation of the electron mean free path in the films. Ni single layers and Ni/Cu multilayers were grown using electrodeposition technique in potentiostatic mode. The films also characterized using x-ray diffraction technique and the results show at least in the growth direction, the films were grown epitaxially and follow their substrate textures

[en] In this work the magnetic properties of Ni_100-xCu_x alloy films of arbitrary composition, which are grown by electrodeposition method onto (111) n-type silicon, has been studied. The surface of samples has been analyzed by Scanning Electron Microscopy. An Alternating Gradient Force Magnetometry device was used to prepare hysteresis loops of Ni_100-xCu_x thin films electrodeposited on Si and their magnetic properties were studied as a function of composition and concentration of Ni. Good control over the average composition of a Ni_100-xCu_x alloy film has been achieved by using Energy-Dispersive X-Ray Spectroscopy where the nominal compositions and the compositions measured for films consisting of different quantities of Cu and Ni deposited in alternation were compared.

[en] Silver thin films were electrodeposited at various thicknesses and current densities, and their surface morphology was studied with scaling analysis based on atomic force microscopy. The Ag thin films show intrinsic anomalous dynamic scaling that was evaluated with a set of local exponents ${\mathrm{\alpha <!--\; ??\; -->}}_{\mathrm{l}\mathrm{o}\mathrm{c}}=0.88$ and ${\mathrm{\beta <!--\; ??\; -->}}_{\mathrm{l}\mathrm{o}\mathrm{c}}=$ 0.61, and global ones, $\mathrm{\alpha <!--\; ??\; -->}=$ 1.75 and $\mathrm{\beta <!--\; ??\; -->}=$ 1.21. Local slope scales with time as $\mathrm{\rho <!--\; ??\; -->}=t^{0.58}$. High-order local roughness exponents decrease with q indicating the existence of multi-scaling of the system (and hence anomalous scaling). All the experimental data collapse into one curve of the anomalous dynamic scaling.

The results demonstrate that the film deposited with higher current density has higher surface roughness and grain size. Calculation of ${\mathrm{\alpha <!--\; ??\; -->}}_{\mathrm{l}\mathrm{o}\mathrm{c}}$ values indicates that they are not dependent on the current density. (paper)

[en] Full text: Magnetic multilayer thin films, consisting of alternating layer of a ferromagnetic and a non-magnetic metal were prepared using electrodeposition technique. Such films exhibit a variety of interesting Physical properties including giant magnetoresistance (GMR). We have successfully electrodeposited nanoscale Ni/Cu multilayers from a single electrolyte containing Ni⁺2,and Cu⁺2 ions. The nominal thickness (calculated from charge passed during growth assuming bulk density and 100% current efficiency) of magnetic and non-magnetic layers were varied between 1 and 5 nm. Both medium and low angle X-ray diffraction study of our films indicate that the electrodeposited Ni/Cu films have a multilayer structure. Two clear satellite peaks surrounding the main (200) peaks are the evidence of this result. The samples then annealed at the presence of Ar gas to prevent them from oxidation, for 1 hour and at temperature varying from 200 to 600 C. X-ray diffraction study then made of to samples after each annealing step. The results show that the satellite peaks were gradually disappeared, indicating the destruction of multilayer structure by annealing process. However some new peaks were appeared that could be attributed to formation of Ni-Cu alloy and nickel oxide or Cu oxide despite of annealing were apparently made at an oxygen free atmosphere. A further investigation of the effect of annealing on the Ni-Cu multilayers gives evidence a transition from multilayer to magnetic granular structure

[en] We fabricated Ni nano wires into arrays of pores on ion track-etched polycarbonate membrane, using electrodeposition technique. The pores which have cylindrical shapes with 6 micron depth and 30 nm width, filled by Ni atoms, fabricating arrays of Ni nano wires. The nano wires then characterized using scanning electron microscopy and transmission electron microscopy. Our results show that although the diameters of nano wires were not perfectly uniform along the length, but they are continue.

[en] Atomic force microscopy (AFM) is used to measure the surface roughness of crystalline Pt thin films as a function of film thickness and growth rate. Our films were electrodeposited on Au/Cr/glass substrates, under galvanostatic control (constant current density), from a single electrolyte containing Pt⁴⁺ ions. Crystalline structure of the films was confirmed by X-ray diffraction (XRD) technique. The effect of growth rate (deposition current density) and film thickness (deposition time) on the kinetic roughening of the films were studied using AFM and roughness calculation. The data is consistent with a rather complex behaviour known as 'anomalous scaling' where both local and large scale roughnesses show power law dependence on the film thickness.

[en] Nickel ferrite nanoparicles with various grain sizes are synthesized using annealing treatment followed by ball milling of its bulk component materials. Commercially available nickel and iron oxide powders are first mixed, and then annealed at 1100°C in an oxygen environment furnace and for 3h. The samples are then milled for different times in an SPEX mill. X-ray diffraction pattern indicates that in this stage the sample is single phase. The average grain size is estimated by scanning electron microscopy (SEM) and x-ray diffraction techniques. Magnetic behavior of the sample at room temperature is studied using a superconducting quantum interference device (SQUID). The Curie temperature of the powders is measured by an LCR—meter unit. The x-ray diffraction patterns clearly indicate that increasing the milling time leads to a decrease in the grain size and consequently leads to a decrease in the saturation magnetization as well as the Curie temperatures. This result is attributed to the spin-glass-like surface layer on the nanocrystalline nickel ferrite with a ferrimagnetically aligned core. (condensed matter: structure, mechanical and thermal properties)