Solid State Science and Technology, Vol. 15, No 1 (2007) 217-222
Corresponding Author: firstname.lastname@example.org
ANNEALING EFFECT ON GIANT MAGNETORESISTANCE OF CoCu/Cu
K.P.Lim, S.A.Halim, Y. Noorhana, H.A.A. Sidek, Z. Abbas,
O. J. Lee, A. Huda and C. E. Lim
Superconductor and thin film laboratory
Department of physics, Faculty of Sciences
43400 Universiti Putra Malaysia
The discovery of giant magnetoresistance (GMR) in multilayer and granular system has stimulated world wide research activities, due to its fundamental significance and potential application. Cu/Cu-Co multilayers were prepared by RF sputtering deposition technique. The as-deposited and annealed (300oC, 15 minutes) samples were characterised by X-ray diffraction and Atomic Force Microscope. The resistances were measured using a four-point probe method to calculate the GMR effect. The microstructure analysis shows that the formation of <111> FCC Cu texture is dominant and small grain size was formed. X-ray diffraction indicated that the reduction of the correlation length is caused by grain coarsening due to growth of crystallites and grain boundaries after heat treatment. The magnetoresistance of Cu/Cu-Co multilayer has been measured as a function of the stacking layers before and after annealing. The MR ratio increase after the annealing process is carried out, but the MR value change within a small range as the number of the stacking layers increase. This shows that the number of stacking layer doesn’t affect the GMR value. The highest GMR value observed is for sample with five stacking layers where 0.61% for as-deposited sample and 0.92% for annealed sample.
. Tae Hyo Lee, Young-woo Lee, CheolGi Kim, Chong-Oh Kim, D.Y. Kim,
Yong Choi, “Free-layer thickness dependence of GMR in
Co/Permalloy/Co/Cu/Co multilayers”, Physica B 328 (2003) 291-294.
. F. Prokert, J.Noetzel, N. Schell, E. Wieser, A. Gorbunov, “Effect of annealing
on the interface structure of cross-beam pulsed laser deposited Co/Cu
multilayers”, Thin Solid Films 416 (2002) 114-121.
. Baibich, M. N., Broto, J. M., Fert, A., Nguyen Van Dau, F., Petroff, F.,
Eitenne, P., Creuzet, G., Friederich, A. and Chazeles, J. (1988). Giant
Magnetoresistance of (001)Fe/(001)Cr Magnetic Superlattices, Physical
Review Letters, 61, pg.2472.
. M. Doi, T. Miyazaki, “Structural changes during annealing of multilayer films
of Cu-Co and Ag-Cu systems”, Journal of Magnetism and Magnetic Materials
126 (1993) 146-148.
. M. Hecker, W. Pitschke, D. Tietjen, C.M. Schneider, “X-ray diffraction
investigations of structural changes in Co/Cu multilayers at elevated
temperatures”, Thin Solid Films 411 (2002) 234-239.