Fe-Pt magnetic multilayers by electrochemical deposition

作者：Liang Defu; Zangari Giovanni^*

来源：Electrochimica Acta, 2011, 56(28): 10567-10574.

DOI：10.1016/j.electacta.2011.01.085

• L1(0) FePt magnetic alloys
• Multilayer
• Electrodeposition
• Magnetic hardening
• Exchange coupling

A series of magnetically soft/hard bilayers (BL) and multilayers with various sublayer thickness and configurations were prepared by electrodeposition from an alkaline solution using potential modulated waveforms and successive thermal annealing. In the as-deposited conditions the equiatomic layers grow with a face centered cubic FCC structure, and the Fe-rich ones with a body-centered cubic BCC structure. Annealing induces partial transformations of both structures to a L1(0) FCT phase. The coercivity of bilayers after annealing at or above 450 degrees C shows a maximum when the Fe-rich layer thickness is 10 nm; this configuration yields up to 45% increase in coercivity compared with single layers of 15 nm equiatomic Fe-Pt. Multilayer structures with fixed 5 or 10 nm Fe-rich layers show a coercivity enhancement similar to that of bilayers, suggesting that a bilayer structure is sufficient to facilitate magnetic hardening while minimizing the overall structure thickness. Either BLs or multilayers with 5 nm thick Fe-rich layers show a single phase magnetization behavior, behaving like a rigid magnet; those with 10 nm thick Fe-rich layers show instead a two stage magnetization switching, implying partial exchange decoupling.

• 出版日期2011-12-1