Ll0 FePt thin films were deposited on an Fe-O underlayer prepared by RF bias sputtering in an oxygen atmosphere for different oxidization time. Very good (001) texture and perfect perpendicular magnetization were obtained in the FePt film on 1-nm-thick Fe-O underlayer after high temperature annealing. The (001) texture evolution was accompanied by fcc-to-fct phase transformation, and both were driven by a recrystallization process. The Fe-O underlayer not only acts as a template, but also provides a stress to help the atom migration during annealing.
Bibliographical noteFunding Information:
The work was supported by the NSF of China under Grants 60490290, 60678008, 10604016, 50771032, and 50771033, the National Basic Research Program of China under Grant 2009CB929201, and the Innovation Program of Shanghai Municipal Education Commission under Grant 09ZZ03. One author, B. Ma, would like to thank Dr. B. Lu in Seagate for help discussions, and Prof. S. Zhou in the Department of Physics for VSM measurements.