Plan-view microstructures of Co/Ru bilayers

Abstract

Plan-view microstructures of two Co/Ru bilayers with a composition of [COI2ARU45A]2 and [CO4OARU35A]2 have been studied by conventional and high resolution electron microscopy. Large differences in electron diffraction and image contrast between the two bilayers were observed, which are recognized as the microstructural variations during the relaxation of large coherent planar strains when the Co layers wet coherently or semicoherently the Ru layers. For the [CO12ARU45A]2 bilayer, the Co layers are unrelaxed from the Ru layers; only one set of electron diffraction patterns was observed, and the image consists of three types of contrasts which are closely related with either the generation and movement of misfit dislocations or large coherent strains. For the [CO4OARU35A]2 bilayer, the Co layers are relaxed basically from the Ru layers; two sets of electron diffraction patterns with double diffraction spots were observed, and the image consists of small irregular areas with moire fringe dots.

Structural properties of molecular beam epitaxy grown Ni/Pt superlattices

“…The microstructure of these Ni-Pt multilayers displays a columnar morphology as observed in most of the MBE or sputter-deposited multilayered systems (Co͞Ru, 14 Co͞Pd and Co͞Au, 6,7 and Co͞Pt 15 ). Such a columnar morphology may have various origins, depending on many factors that can be related either to the growth mode, i.e., to the interfacial wetting, or to a geometrical shadowing effect, or still to structural defects as interfacial defects: steps, dislocations, or weakly misoriented grain boundaries.…”