Characterization of magnetic CoMnP thin films synthesized by electrodeposition technique

Abstract

The ever-increasing performance requirements for the magnetic micro electro mechanical systems (MEMS) such as microactuators, sensors, micromotors and frictionless microgears have motivated the use of new thin film layered microstructures and materials. The most commonly used materials in MEMS are hard magnetic materials, such as cobalt based alloys. In this thesis the properties of hard magnetic CoMnP films electrodeposited in presence of various phosphorous sources such as sodium hypophosphite (NaH2PO2) in presence of the additives such as Urea, Thiourea and Saccharin was studied. Electrodeposited films were subjected to magnetic studies and surface characterization. The increase in magnetic properties of CoMnP films by the effect of various concentration of organic additives such as Urea, Thiourea and Saccharin with various phosphorous sources were studied with respect to thickness of the film. Films were electrodeposited by optimizing solution composition in various current densities and at different time in order to get different thickness and uniform deposit. Elemental composition of the films studied using Energy Dispersive X ray spectrometer (EDS) showed phosphorous content in various percentages with respect to the magnetic properties. All the films were subjected to vibrating sample magnetometer (VSM) studies and were found that organic additive has notable effect on the magnetic properties of these films. Surface structural analysis was carried out using x-ray diffractometer (XRD) and scanning electron microscope (SEM). Reason for change in magnetic properties and structural characteristics were discussed. Hardness and adhesion of the film were also studied. This thesis gives the optimized conditions of electrodeposition and the resultant properties of magnetic films with varying solution composition in presence of organic additives. From the studies it was found that the magnetic properties of the thin films synthesized from chloride bath shows high hard magnetic properties for various concentrations