Orientationally textured thin films of WOx deposited by pulsed laser deposition
journal contributionposted on 2014-12-09, 15:26 authored by Andrew Caruana, Michael Cropper
Pulsed laser deposition from a compound target in an oxygen atmosphere has been used to produce sub-stoichiometric WOx films of 30 nm thickness on Si(100) and SrTiO3(100) substrates. The growth temperature was 500 °C and the pressure of the O2 background was 2.5 × 10−2 mbar. The films have been assessed using x-ray photoelectron spectroscopy, x-ray reflectivity (XRR), x-ray diffraction (XRD) and scanning electron microscopy. The chemical shift of the tungsten 4f states showed that the tungsten was close to fully oxidized. XRR measurements and scanning electron micrographs showed the films on SrTiO3(100) to be much smoother than those on Si(100) which were granular. XRD in the Bragg–Brentano geometry combined with texture analysis showed that the films were textured with the , ,  directions normal to the surface. The films on SrTiO3(100) were found to be biaxially textured with the film directions aligning with those in the substrate. The nature of the texture was sensitive to the laser fluence used. Higher fluence promoted  texture whereas lower fluence promoted  and . Intermediate fluences produced smooth, highly ordered films with biaxial texture. Investigations using the laser repetition rate indicate that the mechanism for the difference is the overall deposition rate, which is affected by fluence. On Si(100) the films were rougher and exhibited only uniaxial texture.
Published inMaterials Research Express
Pages? - ? (18)
CitationCARUANA, A.J. and CROPPER, M.D., 2014. Orientationally textured thin films of WOx deposited by pulsed laser deposition. Materials Research Express, 1 (4), 046408.
Publisher© Institute of Physics
- AM (Accepted Manuscript)
Publisher statementThis work is made available according to the conditions of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0) licence. Full details of this licence are available at: https://creativecommons.org/licenses/by-nc-nd/4.0/
NotesThis article was published in the journal, Materials Research Express [© Institute of Physics] and the definitive version is available at: http://dx.doi.org/10.1088/2053-1591/1/4/046408