Study On Magnetoresistance Coercivity And Aging For [Feni/Cu/Co/Cu](N) Spin Valve Multilayered Films

Spin valve [FeNi/Cu/Co/Cu](N) multilayers were prepared using the electron beam method. The influence of the thickness of magnetic and nonmagnetic layers, preparation process, and coercive force H-c on the magnetoresistance (MR) were studied. Using fairly optimum preparing technology, we prepared many samples with low center held H-0 in the range of 10-20 Oe, the MR merit is larger than 0.2%/Oe, where H-0 is the center magnetic field of the linear region in the MR-H curve. The variation of MR in this linear region is reversible during repeated magnetizing. The change of MR is smaller than 1% for several samples after aging for one year in a dry air chamber at room temperature. Moreover, the MR value decreases greatly when Cr or Cu is added into the Co layer, or Co layers are replaced by SmCO5 magnetic layers. (C) 1997 American Institute of Physics.