Glancing angle EXAFS and x-ray reflectivity are used to study the interface reaction between nickel-chromium alloys and aluminum. the two metals are found to react independently with al, with the first reactions taking place at temperatures similar to those found for the pure metals. this means that ni reacts first with al to form nial3, leaving behind a cr-rich region at the interface. in this cr-rich region some of the ...
X-ray reflectivity has been used to determine the absolute metal density for both metals in bilayers of Al on top of Co, Cr, Cu, Mn, Ni, and Pd. A large variation in density is found with an observed range of 0.87-1.0 of bulk values. The results can be correlated with changes in the defect character as determined by variable-energy positron measurements. The size of the open volume defects systematically increases ...
Glancing angle x-ray reflectivity and exafs measurements have been made on a series of uhv prepared al/ni bilayers with varying amounts of oxygen impurities. these samples show an intrinsic reacted region prior to annealing, and for clean samples further reaction occurs at 250 c. oxygen is found to influence strongly the course of the reaction with an effect which depends on its location. a few percent of impurity within the ...
This paper presents a detailed study of the x-ray diffraction lattice parameters of molecular-beam epitaxy grown Hg(1-x)Cd(x)Te epilayers between 15 and 300 K. The epilayers were grown on (100) oriented CdTe substrates, and varied in thickness (6 to 11 microns) and composition (x=0-0.172). The (400) reflection was measured to determine the lattice parameter a(perpendicular) normal to the film. We also present lattice parameter measurements for a thin cap layer of ...
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