tailieunhanh - Electrodeposition of Co thin Film onto n-Si(111)/Au substrate

Electrodeposition kinetics of Co thin film were investigated and magnetic coercivity of the deposited films were studied using potentiostatic technique and magnetic hyteresis loop measurements. Results showed that the nucleation mechanism of the electrodeposition process changed from instantaneous mode to progressive mode when potential was changed from – V to – V. The magnetic coercivity Hc increases with deposition time and the film with Hc < 15 Oe can be obtained with deposition time t < 5 s. | Journal of Chemistry Vol. 44 6 P. 762 - 765 2006 ELECTRODEPOSITION OF co THIN FILM ONTO n-Si 111 Au SUBSTRATE Received 27 May 2005 MAI THANH TUNG1 CHU VAN THUAN2 NGUyEN HOANG NGHI3 1Faculty of Chemical Technology Hanoi University of Technology international Training Institute for Material Science ITIMS 3Lab. of Amophours Material and Nanocrystalline- Hanoi University of Technology SUMMARY Electrodeposition kinetics of Co thin film were investigated and magnetic coercivity of the deposited films were studied using potentiostatic technique and magnetic hyteresis loop measurements. Results showed that the nucleation mechanism of the electrodeposition process changed from instantaneous mode to progressive mode when potential was changed from V to V. The magnetic coercivity Hc increases with deposition time and the film with Hc 15 Oe can be obtained with deposition time t 5 s. I - INTRODUCTION Magnetic thin films are intensively studied during the last decades due to their various applications in electronics sensor and actuator technology ect. 1 - 5 . Usually the materials for those applications are soft and hard magnetic thin films. Recently new type of films with the so-called Giant Magnetoresistance GMR or Giant Magnetoimpedance GMI effects have been focused due to their very high sensitivity to magnetic field. Among the methods for fabrication of the magnetic thin films electrodeposition technique is one of the most widely used process 1 - 5 . In the previous works we have shown that the multilayer Co Cu with GMR effect can be electrodeposited from a single bath by potential pulse method 2 3 . The magnetic properties of the electrodeposited layer are clearly influenced by the kinetics of the process nucleation and growth particularly the depostion of Co which is the magnetic component of the multilayer 4 . However the kinetics of the Co deposition and the relation between kinetics and morphology magnetic properties are still not well understood. In this .