Fabrication and characterization of L10 FePt nanoparticles

Discontinuous FePt films with thicknesses raging from 0.25 nm to 2 nm were prepared by co-sputtering using high vacuum dc magnetron sputtering. Ex-situ anneals in one atmosphere of a flowing reducing gas, argon with 3% hydrogen, were used to stabilize the isolated cluster morphology and to induce ordering. Composition ratios were confirmed with RBS and extensive characterization of the nanoparticles was done with transmission electron microscopy (TEM). The particle was found to depend on the annealing temperature and thickness. For 0.25 nm deposition, the typical particle size increases from 2.5 nm to 5 nm with annealing temperature increasing from 500°C to 800°C For the thickest films of 2 nm deposition, particle size increased from 5.5 nm to 10 nm with increasing annealing temperature.