METHOD FOR PRODUCING FePt NANOPARTICLE, AND METHOD FOR PRODUCING MAGNETIC RECORDING MEDIUM HAVING FePt MAGNETIC NANOPARTICLE ARRAY

摘要

PROBLEM TO BE SOLVED: To provide FePt nanoparticles having a uniform shape, a uniform particle size and uniform magnetic properties; particularly FePt magnetic nanoparticles having a face centered tetragonal (fct) structure; further an FePt magnetic nanoparticle array in which the particles are arranged on a substrate so that the directions of the axes along which the particles are easily magnetized are uniformly vertical; and an ultrahigh-density magnetic recording system by applying such FePt magnetic nanoparticles and the array thereof to a magnetic recording medium.;SOLUTION: The method for producing the FePt nanoparticles with an average particle diameter of 3 to 20 nm comprises the steps of: producing nuclear particles of metallic Pt from a solvent solution containing a Pt compound, a reducing agent and a first agent for dispersing particles, through a reduction reaction; adding an Fe compound and a second agent for dispersing particles to the solvent solution to precipitate metallic Fe on the nuclear particles of Pt and form nanoparticles containing Fe and Pt; and subsequently aging the nanoparticles at 185 to 320°C to make the Pt atom and the Fe atom mutually diffused and form an alloy.;COPYRIGHT: (C)2009,JPO&INPIT