MAGNETORESISTANCE EFFECTS IN NI-FE-CO CU/CO-PT TRILAYERS/

Magnetoresistance effects in Ni-Fe-Co/Cu/Co-Pt trilayers have been inv estigated with various thicknesses of each layer. The Co-Pt layers exh ibited high coercivities when deposited directly on Si substrates to a thickness of more than 3.2 nm. An antiparallel alignment of the magne tizations in the Ni-Fe-Co and the Co-Pt layers with each other occurre d under low magnetic fields because the Co-Pt layer had a higher coerc ivity than the Ni-Fe-Co layer; thus the trilayers have magnetoresistan ce ratios higher than 4.0% for Cu layer thicknesses between 1.5 nm and 3.0 nm. The thermal stability of these trilayers was also investigate d. These trilayers maintained high magnetoresistance ratios after anne aling up to 300 degrees C.