The morphology and texture of Cu nanorod films grown by controlling the directional flux in physical vapor deposition

We report the creation of unusual biaxial textures in Cu nanorod films, through the control of the incident vapor flux during oblique angle deposition. High-density twin boundaries were formed using a periodic azimuthal swing rotation of the substrate while the incident angle of the Cu flux was fixed at 85° with respect to the surface normal. In contrast, depositions on stationary substrates resulted in nanorod films with a much lower density of twinned crystals. From transmission electron microscopy and x-ray pole figure analysis, the nanorod axis was shown to coincide approximately with the [Formula: see text] crystallographic directions. We also observed the branching of these nanostructures into 'nanotrees'. This branching was attributed to the creation of edge dislocations during the deposition and was particularly prevalent for the case of swing rotation. The mechanisms for the development of texture, twinning, and branching in these nanostructures are discussed.