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Room-temperature x-ray diffraction and Mössbauer effect techniques have been used to characterize the structural features and local atomic environments of sputtered Fe[sub 51]Pt[sub 49] thin films following various isothermal treatments. Both techniques show that no significant changes occur in the chemically ordered L1[sub 0] tetragonal phase after it has formed. In contrast, changes in the disordered face-centered-cubic (fcc) phase are observed prior to the transformation into the ordered tetragonal phase. Mössbauer measurements indicate the development of increasing short-range order in the disordered fcc phase with increasing annealing temperature. Asymmetries in the fcc x-ray diffraction profiles also suggest the presence of lattice distortions caused by atomic size differences commonly found in the quenched disordered fcc phase of materials that form ordered structures. Quasi-real-time kinetic measurements of the disorder→order transformation in sputtered Fe[sub 51]Pt[sub 49] thin films within the temperature range 300 °C≤T≤400 °C have also been conducted using high-temperature x-ray diffraction techniques. Significant differences are observed between the kinetic parameters determined in this study and those of previous reports. It is proposed that these differences arise from the lower temperature range investigated in the present work, where the gradual changes occurring in the fcc phase can influence the rate of the ordering transformation. Furthermore, because the initial state of disorder in Fe[sub ∼50]Pt[sub ∼50] films can be influenced by the deposition conditions, variability in the low-temperature ordering kinetics should be expected among Fe[sub ∼50]Pt[sub ∼50] films prepared under different conditions. © 2003 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Examines the magnetic and structural properties of sputtered copper iron (CoFe) films. Correlation between coercivity and microstructure of CoFe films; Formation of complex, fixed patterns in the domain walls of hard CoFe film; Structural origins for the wide variation in coercivity obtained with different substrates, deposition temperature and thickness.

Provides information on a study of the preparation of tunnel junctions comprised of two magnetic metal layers separated by a thin insulating oxide layer. Methodology used to conduct the study; Identification on HfO2, a candidate material for tunneling junctions; Cross-sectional images of HfO2 tunnel junctions; Results of the study.

Studies spin-polarized electron tunneling by growing MOM junctions where M is a magnetic transition metal and O a reactively sputtered oxide. Range of oxide thickness; Structural, magnetic, and transport properties of tunnel junctions.

Studies the tunneling properties of sputtered oxide barriers in lead (Pb)/oxide/ferromagnet junctions. Making the initial oxide/ferromagnet bilayer without breaking vacuum; Exposition of the bilayer to the atmosphere before the deposition of a Pb counterelectrode in a separate vacuum chamber.