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Research was conducted to examine the sputtered multilayers of carbon and alumina. The samples were prepared by rf or rf magnetron sputtering in a high vacuum chamber while the Raman spectra were recorded at room temperature with an Ar-ion laser in a 180 degree scattering geometry. Results showed that interdiffusion does not happen below 700 degrees. They also indicated that abnormal-incidence reflectivity of more than 40% can be achieved with a sample characterized by 1.2 nm carbon and 0.9 nm aluminum with an interface roughness of 0.3 nm.

Researchers used x-ray diffraction to investigate the thermal behavior of molybdenum Al2O3 multilayers. Multilayer stacks of alternating materials have numerous applications but the type of metal used determines the stability limit of the multilayer stack. The use of sputtered molybdenum created a multilayer stack which was stable up to 900 degrees centigrade, but temperatures of 1000 degrees centigrade cause the creation of large molybdenum crystallites and the complete destruction of the layered structure.

Sputtered metal/Al2O3 multilayers were studied with respect to their applicability as x-ray mirrors in high temperature environments. The rf-sputtering method produces layered structures with interface roughness of only 0.2 nm. In situ resistance measurements characterize the percolation process and indicate the lower thickness limits for the selected materials which produce minimum modulation periods of about 2 nm.

Co/Al2O3 multilayers prepared by radio-frequency sputtering techniques on sapphire (1120) substrates exhibit CO percolation thresholds between 15 and 2.5 nanometers. When the multilayers are more than 3 nanometers thick they exhibit continuous metallic layers. The growth of the Co/Al2O3 occurs in a polycrystalline manner.

The structural phase stability of epitaxial FeCo alloy films sputtered on MgO(001) substrates is determined by X-ray scattering and magneto-optical Kerr effect. The structural phase stability is stimulated by the MgO(001) substrates. A body centered cubic (001) growth is exhibited by alloy films which are thicker than 20 nanometers. When pure Co is used, a face centered cubic (001) structure is obtained. The Co(100) axis is parallel to the MgO(110) axis.

An analysis of the spin polarized neutron reflectivity data on a Co/Cu(111) superlattice, shows that not only the magnitude but also the orientation of the average magnetic moment of each layer can be extracted by studying the polarization of the reflected beam. Detailed conclusions about the exchange coupling of magnetic layers across nonmagnetic interlayers and information on the magnetic in-plane anisotropy in such systems is obtained by this method. The macroscopic magnetic properties measured by the magneto optic Kerr effect, coincides with the spin polarized neutron reflectivity results, indicating a newly discovered uniaxial anisotropy in this system.

Ferromagnetic resonance studies of the influence of MgO and Al2O3 substrates on the magnetic properties of Fe and Co thin films reveal that the substrate and films interact and that the film anisotropy magnetocrystalline constants depend on the thickness of the substrates. Co films on MgO substrates display a four-fold in-plane anisotropy while Co films on Al2O3 substrates display uniaxial in-plane anisotropy, indicating that substrate materials determine the type of anisotropy. The temperature of the substrates also contribute to the thickness effect on anisotropy.