Das, Arpita (2010) Prodding Magnetic Properties of Electrodeposited Co/Cu
and Ni/Cu alloy Films by Scanning Probes. MTech thesis.
Magnetic thinfilms, either granular or multilayed, are essential components for the design of magnetic devices. In order to design magnetic material for specific application, it is necessary to understand the influence of preparation process and preparation materials on the resulting parameter such as grain size and magnetic structure. Magnetic domain structure is responsible for the magnetic behavior of ferromagnetic material. Magnetic domains are the regions having uniform magnetization. There are different energies acting in a magnetic system. Domain structure always has its origin in the possibility of lowering the energy of the system by going from a saturated configuration with magnetic energy to a domain configuration with a lower energy. Magnetic force microscope technique provides the internal structure of domain walls and the spin distributions within domains as well as the general feature of the domain structure.During MFM measurement, there are two forces acting on the tip: magnetic and Vander waal’s forces. Hence in MFM, the signal contains both information of surface topography and surface magnetic property generated by Vander Waal’s and magnetic forces respectively. MFM can image domain structure in various recording media, materials, and superconductor or,increasingly, small particles, all with sub 100 nm special resolutions. In this work we prepare the Cu, Co and Ni thin films with Co-Cu alloy and Ni-Cu alloy thin film by electrodeposition method at different deposition potential and concentration of electrolyte at 25°C Films are characterized by XRD, SEM, and MFM. Scahifker and Hills model was used for study of nucleation and growth phenomena for electrochemically deposited thin film by cyclic voltammetry and chronoamperometry.Different deposition potentials were selected for the deposition for all the films. To set the deposition potential in all the systems Cyclic Voltammetry is done. The thickness of films lies in the range of 300-400 nm. The phases of the deposits are confirmed by the XRD analysis. As the deposition potential increases the crystallite size of the deposits decreases which is also confirmed by the morphological analysis by SEM. Magnetic domain structure and topography is analyzed by MFM. The topographic figure indicates the presence of aggregates of different sizes on the electrode surface. The films contain two distinct areas, one plane and the other with random fluctuations. The plane regions are assumed to have no contribution to the phase shift of the tip, remarked as non-magnetic phase. As Cu concentration decreases in the alloy solution, the domains are larger in size.
|Item Type:||Thesis (MTech)|
|Subjects:||Engineering and Technology > Metallurgical and Materials Science > Coatings|
|Divisions:||Engineering and Technology > Department of Metallurgical and Materials Engineering|
|Deposited By:||Ms Arpita Das|
|Deposited On:||29 Jun 2010 14:48|
|Last Modified:||29 Jun 2010 14:49|
|Supervisor(s):||Mallik, A and Ray, B C|
Repository Staff Only: item control page