Incident flux angle induced crystal texture transformation in nanostructured molybdenum films

Molybdenum films were observed to undergo a dramatic change in crystal texture orientation when the incident flux angle was varied in an oblique angle sputter deposition on amorphous substrates. Reflection high-energy electron diffraction pole figure and scanning electron microscopy were used to analyze in detail the texture orientation of the films. The normal incident deposition resulted in a fiber texture film with the minimum energy (110) crystal plane parallel to the substrate surface. A (110)[1 (1) over bar0] biaxial texture was observed for the samples grown with low incident angles of less than 45 degrees, with respect to the surface normal. On the other hand, for an oblique angle deposition of larger than 60 degrees, a (111)[11 (2) over bar] biaxial texture was observed and appeared to be consistent with a zone T structure where the geometrically fastest growth [001] direction of a crystal plays a dominant role in defining the texture. We argue that a structural transition had occurred when the incident flux was varied from near normal incidence to a large angle. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4737403]