Effect of Au cap layer on the magnetic properties and the microstructure for FePt thin films

Journal Article · Mon Oct 11 04:00:00 EDT 2004 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.1800285· OSTI ID:20634355

Yuan, F T; Chen, S K; Chang, W C; Horng, Lance ^[1]

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1. Department of Material Science and Engineering, Feng Chia University, Taichung 407, Taiwan (China)

We have investigated the effect of interfacial diffusion on the magnetic properties of Au/Fe{sub 51}Pt{sub 49} bilayer thin films. The samples were prepared in two stages. First, an ordered Fe{sub 51}Pt{sub 49} continuous thin film was sputtered on a quartz substrate. Then an aurum cap layer was deposited onto the Fe{sub 51}Pt{sub 49} film at room temperature, followed by a postannealing at 300-800 deg. C to promote the interfacial diffusion. A high coercivity of 23.5 kOe was achieved in the isotropic polycrystalline FePt-based film. Transmission electron micrographs indicate that the bilayer sample exhibits Ll{sub 0} ordered FePt grains with a diameter of about 20 nm, which were partially isolated by Au phase. We consider that the isolation of FePt Ll{sub 0} grains and the grain refining effect can be two contributory factors for the enhanced coercivity.

• OSTI ID: 20634355
• Journal Information: Applied Physics Letters, Journal Name: Applied Physics Letters Journal Issue: 15 Vol. 85; ISSN APPLAB; ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ANNEALING
BINARY ALLOY SYSTEMS
COERCIVE FORCE
DIFFUSION
FERROMAGNETIC MATERIALS
GOLD
GRAIN REFINEMENT
GRAIN SIZE
HYSTERESIS
IRON ALLOYS
MAGNETIC PROPERTIES
PLATINUM ALLOYS
POLYCRYSTALS
QUARTZ
SUBSTRATES
TEMPERATURE RANGE 0273-0400 K
THIN FILMS
TRANSMISSION ELECTRON MICROSCOPY