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The use of differential scanning calorimetry in conjunction with x-ray and electron diffraction, to investigate the Al to L1(sub 0) ordering transformation inbinary FePt films with compositions in the range of 47.5-54.4 at. percentage Fe is done. The lattice parameter of the A1 phase and the c/a ratio of the L1(sub 0) phase decrease with the increase in Fe content.

Research was conducted to study the microstructure and the room-temperature hysteretic magnetic characteristics of sputtered, 10 nm thin films of equiatomic binary alloys of CoPt and FePt using transmission electron microscopy (TEM) and a superconducting quantum interference device magnetometer. Dark-field TEM images were digitally analyzed to characterize transformation from an atomically disordered, face-centered-cubic structure to the L1(sub 0) ordered structure. It has been concluded that a direct relationship exists between the ordered volume fraction and the coercivity, with the maximum value of the coercivity coinciding with the fully ordered structure.

Surface accumulation of Co/Cu and Co/Cr thin films are measured by X-ray photoelectron spectroscopy to study the kinetics of grain boundary diffusion. Annealing facilitates the accumulation of underlayer materials on the film's free surface by diffusion. Activation energies coefficients are measured and correlated with magnetometer measurements at different annealing conditions. Co grain boundary stuffing with Cu and Cr atoms reduces the intergranular exchange and magnetostatics.

Amorphous CoSi2 is studied to determine the effect of ion beam irradiation on crystalline kinetics of amorphous CoSi2. Three dimensional growth of existing nuclei influences the crystallization kinetics of as-deposited CoSi2. The existing nuclei is amorphized by ion beam irradiation of as-deposited CoSi2. Direct amorphization is caused by heavy-ion irradiation. Variation in the growth mode from three-dimensional to two-dimensional decreases the density of preexisting nuclei.

The correlation between the deposition conditions, the beta to alpha phase transformation and stress relaxation in tantalum thin films was investigated. The results showed that phase transition resulted in a significant decrease in the electrical resistance of tantalum thin films. In addition, phase transformation also caused complete stress relaxation in the material. For tantalum films with intrinsic compressive stresses, the main stress relief mechanism was phase transition. However, phase transition had a lesser effect on intrinsically tensile films.

A study was done on the crystallization of coevaporated amorphous Co-Si alloys with different compositions using heat-flux differential scanning calorimetry, transmission electron microscopy as well as in situ stress and resistance measurements. It was shown that structural relaxation of the amorphous alloys preceded crystallization. In addition, alloys resembling disilicides exhibit a one-step crystallization process with an activation energy of 1.3 eV and an Avrami exponent of three.

The phase formation kinetics of niobium/aluminum multilayers was investigated using scanning calorimetry, x-ray diffraction and cross-sectional transmission electron microscopy. The results showed that annealing of the Nb/Al structure initially produced an NbAl3 intermetallic. The formation of the NbAl3 was characterized by a two-phase process. An Al5 superconducting phase followed.

The A1 to L1(sub 0) ordering transformation in binary FePt films with compositions in the range of 47.5 to 55 at. percentage Fe and in ternary alloys of FePt with Cu, Co, Ag and Au is examined. The kinetic ordering temperature is increased by the ternary additions of Co (28 at. %), Ag (11 at.%) and Au (7 and 12 at.%).

Research into model bilayers of fully ordered L1(sub O) CoPt with thicknesses of 25, 50 or 100 nm is presented. There was strong evidence that annealing the bilayer L1(sub O)-type CoPt/Co film system gives rise to thermally driven grain growth and raised epitaxial intergranular registry.

The thermodynamic and kinetic parameters of the A1 to L[1.sub.0] transformation is investigated and compared for FePt, FeNiPt and FeCuPt using nonisothermal differential scanning calorimetry. It is revealed that each ternary alloy shows potential for heat assisted magnetic recording applications.

The kinetics of the A1 to L[I.sub.0] are provided in the form of time-temperature-transformation diagrams, which are calculated using the data for 1 [micro]m thick FePt and FeCuPt thin films and three variations of the Johnson-Mehl-Avrami-Kolmogorov kinetic theory. The transformation in nanoparticles is found to be highly dependent on the nucleation of the L[1.sub.0] phase.

Time-temperature-transformation diagrams describing the A1 to [L1.sub.0] transformation in 1 mum thick FePt and FeCuPt alloy films are constructed from data obtained using nonisothermal differential scanning calorimetry in conjunction with a limited number of isothermal anneals. The results are extended to 10 nm thick films using geometric corrections, which are found to transform approximately five times more slowly than thicker films.

Two series of epitaxial CoPt and FePt films, with nominal thicknesses of 42 or 50 nm, were prepared by sputtering onto single-crystal MgO(001) substrates in order to investigate the chemical ordering and the resultant magnetic properties as a function of alloy composition. Conclusion reveals that nonstoichiometric L1(sub 0) CoPt and FePt, with a slight excess of Co or Fe, are preferable for applications requiring the highest anisotropies.

The impact of 11 alloying elements like Mg, In, Al, Ag,Ti, Sn, Co, Nb and B on the resistivity and grain structure of copper is analyzed. The results show that the control of the Cu microstructure via codeposition and subsequent annealing is not seen as a suitable procedure for copper interconnects.

Ferromagnetic bilayer thin film samples of the well characterized CoPt/Co bilayer exchange-spring system is discussed to supply experimental and theoretical estimates of the exchange field supporting the interfacial exchange coupling across the interphase interface. The surface roughness of the films as measured by atomic force microscopy of the CoPt layer is approximately 1.4 nm.

A study was conducted, by combining in situ synchrotron x-ray diffraction (XRD) with ex situ electron diffraction and differential scanning calorimetry (DSC), to investigate the sequence and kinetics of metastaable and equilibrium phase formation in sputter deposited multiplayer thin films. The result shows the sequence of phases for the reaction of Ti/3Al multiplayer films to begin with the formation of metastaable, cubic Ll2-TiAl3 and to result in the formation of equilibrium DO22-TiAl3.

A new study aims to provide a classification scheme for the dissociation behavior of dilute, immiscible Cu-alloy thin films.

A general methodology that combines conventional and newly developed image processing algorithms to extract and combine information from multiple, optimized transmission electron microscopy (TEM) micrographs is introduced. Systematic analysis of microstructures of thin films obtained from TEM micrographs and comparison with the results from a conventional, manual approach has validated the technique. Data from structural analysis show a good agreement between the two methods.