The Coupled Magnetic Field Effects on the Microstructure Evolution and Magnetic Properties of As-Deposited and Post- Annealed Nano-Scaled Co-Based Films — Part I

Abstract

Superimposed external magnetic fields during electrodeposition process offers the possibility to tailor microstructure and properties of the obtained films in a very efficient, contactless, and easily controllable way, what is caused by so-called magnetohydrodynamic MHD effect. On the other hand, the nonequilibrium state of aselectrodeposited nanocrystalline films provides a strong thermodynamic potential for microstructural transformation. This means that the benefit effect of magneto-electrodeposition on a nanocrystalline film can be completely consumed by a thermal exposure at relatively low temperature. Magnetic field annealing has been confirmed to be useful for tailoring the microstructure of as-deposited nanocrystalline films for their widespread uses.The particular interest of this book Chapter Growth of Co-based magnetic thin films by magnetic fields MF assisted electrodeposition and heat treatment is the finding that the microstructure and magnetic properties of nanocrystalline Co-based alloys and oxides like CoX X= Cu, Ni, NiP, FeO are improved by imposition of MF during elaboration process or post-annealing process. "ccording to the previous study, the targeted scientific activities pay more attention to develop alloys and oxides in nanoscale using pulsed electrodeposition assisted by high magnetic field HMF . Note Since the instantaneous current density during pulse electrodeposition is higher than that during direct current plating, the microstructure of the nano-scale electrodeposits can be more easily controlled by perturbing the desorption/adsorption processes occurring in the pulse electrodeposition process .During the experiment, high magnetic field is an in-situ method for the control of electrodeposition process. The obtained material is then annealed or oxidized after

Tailoring the Morphology, Structure and Magnetic Properties of Electrodeposited CoFe Films onto Si(100) by In-Situ Uniform and Gradient High Magnetic Fields

“…9 In recent years, magnetoelectrodeposition, 10 as an emerging interdisciplinary field, has received broad attention from a number of research groups. 11 It is known that magnetic field has remarkable influences on the movement of electroactive species, increasing the limiting current density 12 and causing the changes of the morphology 13-15 and composition 16 of the deposited films. The major effects of magnetic field on the electrodeposition process can be explained with magnetohydrodynamic (MHD) effect induced by Lorentz force ( F L = j × B, where j is thr current density in A m −2 , B is the applied field in tesla), 17 which acts on electroactive species and affects the mass transport process toward the electrode.…”