Effects of AG on structural and magnetic properties of FePt thin films

In order to improve structural and magnetic performance, Ag was added into perpendicular FePt thin films by cosputtering and sequential sputtering. Cosputtered with Ag, FePt grain size and magnetic exchange coupling were reduced with increasing Ag content. A study on alloying of FePt-Ag indicated that most Ag atoms formed a separate phase from FePt. The coercivity enhancement was associated with the pinning effect of Ag and improvement in ordering.In FePt/Ag/FePt sequential deposition, Ag diffused throughout the FePt film with predominant segregation to the film surface. As a result, media noise was reduced and SNR was improved.Ag could be used as underlayer to promote FePt ordering. Film structure and magnetic properties closely depended on deposition conditions and the thickness of Ag layer. Ag may be a promising candidate for heat sink layer in FePt HAMR system because of its close lattice mismatch with FePt and good thermal conductivity.

Author dc:creator

• ZHOU YONGZHONG

• FePt, Perpendicular Magnetic Recording, High Anisotropy, Thin Film, Ordering, Texture