Interface composition between Fe{sub 3}O{sub 4} nanoparticles and GaAs for spintronic applications

Journal Article · Thu Aug 28 00:00:00 EDT 2014 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.4893958· OSTI ID:22314353

Hihath, Sahar ^[1]; Kiehl, Richard A. ^[2]

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1. Department of Chemical Engineering and Materials Science, University of California, Davis, California 95695 (United States)
2. Department of Electrical and Computer Engineering, University of California, Davis, California 95695 (United States)

Recent interest in spintronic applications has necessitated the study of magnetic materials in contact with semiconductor substrates; importantly, the structure and composition of these interfaces can influence both device functionality and the magnetic properties. Nanoscale ferromagnet/semiconductor structures are of particular interest. In this study, the interface structure between a monolayer of ferromagnetic magnetite (Fe{sub 3}O{sub 4}) nanoparticles and a GaAs substrate was studied using cross-sectional transmission electron microscopy techniques. It was found that a continuous amorphous oxide interface layer separates the nanoparticles from the GaAs substrate, and that iron diffused into the interface layer forming a compositional gradient. Electron energy-loss near-edge fine structures of the O K absorption edge revealed that the amorphous oxide is composed of γ-Fe{sub 2}O{sub 3} directly underneath the Fe{sub 3}O{sub 4} nanoparticles, followed by a solid solution of Ga{sub 2}O{sub 3} and FeO and mostly Ga{sub 2}O{sub 3} when approaching the buckled oxide/substrate interface. Real-space density functional theory calculations of the dynamical form factor confirmed the experimental observations. The implication of the findings on the optimization of these structures for spin injection is discussed.

• OSTI ID: 22314353
• Journal Information: Journal of Applied Physics, Vol. 116, Issue 8; Other Information: (c) 2014 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
ENERGY LOSSES
FERRITES
FINE STRUCTURE
FORM FACTORS
GALLIUM ARSENIDES
GALLIUM OXIDES
INTERFACES
IRON
IRON OXIDES
K ABSORPTION
LAYERS
MAGNETIC PROPERTIES
NANOPARTICLES
NANOSTRUCTURES
SOLID SOLUTIONS
SPIN
SUBSTRATES
TRANSMISSION ELECTRON MICROSCOPY