Nanocrystallization and amorphization induced by reactive nitrogen sputtering in iron and permalloy

Journal Article · Fri Jul 01 04:00:00 EDT 2005 · Physical Review. B, Condensed Matter and Materials Physics

DOI:https://doi.org/10.1103/PhysRevB.72.024202· OSTI ID:20719124

Gupta, Rachana; Gupta, Mukul ^[1]

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1. Laboratory for Neutron Scattering, ETHZ and PSI, Paul Scherrer Institut, Villigen, CH-5232 (Switzerland)

Thin films of iron and permalloy (Ni{sub 80}Fe{sub 20}) were prepared using an Ar+N{sub 2} mixture with a magnetron sputtering technique at ambient temperature. The nitrogen partial pressure during the sputtering process was varied in the range of 0{<=}R{sub N{sub 2}}{<=}100%, keeping the total gas flow at constant. At lower nitrogen pressures (R{sub N{sub 2}}{<=}33%), both Fe and NiFe first form a nanocrystalline structure, and an increase in R{sub N{sub 2}} results in the formation of an amorphous structure. At intermediate nitrogen partial pressures, nitrides of Fe and NiFe were obtained, while at even higher nitrogen partial pressures, nitrides themselves became nanocrystalline or amorphous. The surface, structural, and magnetic properties of the deposited films were studied using x-ray reflection and diffraction, transmission electron microscopy, polarized neutron reflectivity, and using a dc extraction magnetometer. The growth behavior for amorphous film was found to be different as compared with poly or nanocrystalline films. The soft-magnetic properties of FeN were improved on nanocrystallization, while those of NiFeN were degraded. A mechanism inducing nanocrystallization and amorphization in Fe and NiFe due to reactive nitrogen sputtering is discussed in the present article.

• OSTI ID: 20719124
• Journal Information: Physical Review. B, Condensed Matter and Materials Physics, Journal Name: Physical Review. B, Condensed Matter and Materials Physics Journal Issue: 2 Vol. 72; ISSN 1098-0121
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
AMORPHOUS STATE
CRYSTALLIZATION
CRYSTALS
DEPOSITION
FERROMAGNETIC MATERIALS
IRON
MAGNETIC PROPERTIES
NANOSTRUCTURES
NEUTRONS
NITRIDES
NITROGEN
PARTIAL PRESSURE
PERMALLOY
REFLECTIVITY
SPUTTERING
THIN FILMS
TRANSMISSION ELECTRON MICROSCOPY
X RADIATION
X-RAY DIFFRACTION