Effect of sputtering methods on the magnetic properties and microstructure of FePt:Ag magnetic granular thin films

Co-sputtering and multilayer-sputtering methods were employed to prepare FePt:Ag granular thin films. The magnetic properties, magnetic domain patterns and microstructure of thin films were measured or investigated by VSM, MFM and TEM, respectively. It was found that FePt phase transition started at a lower annealing temperature in the multilayer-sputtered FePt:Ag granular films. However, co-sputtering method produced granular films with higher coercivity, as well as smaller and more uniform grain size and discrete magnetic domain patterns according to the TEM and MFM observations.