Title :
Characterization of a Nano-Oxide Layer in a Pseudo Spin Valve by Complex Magneto-Impedance Spectroscopy
Author :
Chien, W.C. ; Peng, T.Y. ; Hsieh, L.C. ; Lo, C.K. ; Yao, Y.D.
Author_Institution :
Dept. of Phys., Nat. Chung Cheng Univ., Chia-Yi
Abstract :
The ac properties of a pseudo spin valve (PSV) consisting of NOL top/Co/Cu/Co/Ni80Fe20/NOLbottom with a top and bottom nano-oxide layer (NOL) were studied as functions of NOL and thickness, d, by magneto impedance spectroscopy. The NOLs were formed by natural oxidizing the top and bottom ferromagnetic or Ta layers in situ. The increase in the thickness of NOL resulting in the increment of effective capacitance caused the shift of roll-off frequency from low to high. The frequency dependence behavior of this NOLtop/PSV/NOLbottom system can be modeled by equivalent circuit theory. PSV with a different NOL structure can be checked by such a nondestructive analysis method
Keywords :
cobalt alloys; copper alloys; iron compounds; magnetoresistance; nanotechnology; nickel compounds; spin valves; Co-Cu-Co-Ni80Fe20; equivalent circuit theory; magneto-capacitance; magneto-impedance spectroscopy; nano-oxide layer characterization; natural oxidation; nondestructive analysis method; pseudo spin valve; roll-off frequency; Capacitance; Electrochemical impedance spectroscopy; Equivalent circuits; Frequency; Iron; Magnetic analysis; Magnetic films; Magnetic tunneling; Physics; Spin valves; Magneto-capacitance; magneto-impedance; nano-oxide layer; pseudo spin valve; roll-off frequency;
Journal_Title :
Magnetics, IEEE Transactions on
DOI :
10.1109/TMAG.2006.879730
