Thickness Effect on the Solid-State Reaction of a Ni/GaAs System.

Ni thin films with different thicknesses were grown on a GaAs substrate using the magnetron sputtering technique followed by in situ X-ray diffraction (XRD) annealing in order to study the solid-state reaction between Ni and GaAs substrate. The thickness dependence on the formation of the intermetallic phases was investigated using in situ and ex situ XRD, pole figures, and atom probe tomography (APT). The results indicate that the 20 nm-thick Ni film exhibits an epitaxial relation with the GaAs substrate, which is (001) Ni//(001) GaAs and [111] Ni//[110] GaAs after deposition.

Direct Observations of the Structural Properties of Semiconducting Polymer: Fullerene Blends under Tensile Stretching.

We describe the impact of tensile strains on the structural properties of thin films composed of PffBT4T-2OD π-conjugated polymer and PCBM fullerenes coated on a stretchable substrate, based on a novel approach using in situ studies of flexible organic thin films. In situ grazing incidence X-ray diffraction (GIXD) measurements were carried out to probe the ordering of polymers and to measure the strain of the polymer chains under uniaxial tensile tests. A maximum 10% tensile stretching was applied (i.