Modification of the structural and magnetic properties of granular FePt films by seed layer conditioning

Journal Article · Wed Jan 07 00:00:00 EST 2015 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.4905422· OSTI ID:22399202

Neu, V.; Schultz, L.; Mehta, V.; Jain, S.; Reiner, J.; Mosendz, O.; Hellwig, O.; Weller, D. ^[1]

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1. HGST-A Western Digital Company, 3403 Yerba Buena Rd, San Jose, California 95135 (United States)

The steadily increasing amount of digital information necessitates the availability of reliable high capacity magnetic data storage. Here, future hard disk drives with extended areal storage densities beyond 1.0 Tb/in{sup 2} are envisioned by using high anisotropy granular and chemically L1{sub 0}-ordered FePt (002) perpendicular media within a heat-assisted magnetic recording scheme. Perpendicular texturing of the [001] easy axes of the individual grains can be achieved by using MgO seed layers. It is therefore investigated, if and how an Ar{sup +} ion irradiation of the MgO seed layer prior to the deposition of the magnetic material influences the MgO surface properties and hereby the FePt [001] texture. Structural investigations reveal a flattening of the seed layer surface accompanied by a change in the morphology of the FePt grains. Moreover, the fraction of small second layer particles and the degree of coalescence of the primarily deposited FePt grains strongly increases. As for the magnetic performance, this results in a reduced coercivity along the magnetic easy axis (out of plane) and in enhanced hard axis (in-plane) remanence values. The irradiation induced changes in the magnetic properties of the granular FePt-C films are traced back to the accordingly modified atomic structure of the FePt-MgO interface region.

• OSTI ID: 22399202
• Journal Information: Journal of Applied Physics, Vol. 117, Issue 1; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ANISOTROPY
ARGON IONS
COALESCENCE
COERCIVE FORCE
GRANULAR MATERIALS
INTERFACES
INTERMETALLIC COMPOUNDS
IRON
IRRADIATION
LAYERS
MAGNESIUM OXIDES
MAGNETIC DISKS
MAGNETIC MATERIALS
MAGNETIC PROPERTIES
MORPHOLOGY
PHYSICAL RADIATION EFFECTS
PLATINUM
SURFACE PROPERTIES
TEXTURE
THIN FILMS