CoPt/Ag nanocomposites for high density recording media

Nanocomposite CoPt/Ag films have been successfully fabricated and their mic rostructural and magnetic properties have been investigated for potential a pplications in magnetic recording media. This was done by first making sput tered CoPt/Ag multilayers with the face-centered cubic (fcc) structure whic h is magnetically soft and then annealing the multilayers to transform the fcc phase to the highly anisotropic face-centered tetragonal phase (fct) wh ich is magnetically hard. The final nanocomposite structure consists of CoP t nanoparticles with the hard fct phase embedded in a fcc Ag matrix. Large values of coercivity in the range of 1-17 kOe were achieved with grain size s in the range of 7-100 nm, respectively. (C) 1998 American Institute of Ph ysics. [S0003-6951(98)01549-6].