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Articles you may be interested inThermoelectric properties of epitaxial ScN films deposited by reactive magnetron sputtering onto MgO(001) substrates J. Appl. Phys. 113, 153704 (2013); 10.1063/1.4801886Influence of working gas pressure on structure and properties of WO 3 films reactively deposited by rf magnetron sputtering J.Influence of the target-substrate distance on the properties of indium tin oxide films prepared by radio frequency reactive magnetron sputtering Microstructural evolution and Poisson ratio of epitaxial ScN grown on TiN(001)/MgO(001) by ultrahigh vacuum reactive magnetron sputter deposition ScN layers, 180 nm thick, were grown on MgO͑001͒ substrates at 750°C by ultra-high-vacuum reactive magnetron sputter deposition in pure N 2 discharges. N/Sc ratios, determined by Rutherford backscattering spectroscopy, were 0.98Ϯ0.02. X-ray diffraction -2 scans and pole figures combined with plan-view and cross-sectional transmission electron microscopy showed that the films are strongly textured, both in plane and along the growth direction, and have a columnar microstructure with an average column width near the film surface of 30Ϯ5 nm. During nucleation and the early stages of film growth, the layers consist of approximately equal volume fractions of 002-and 111-oriented grains. However, preferred orientation evolves toward a purely 111 texture within Ӎ40 nm as the 002 grains grow out of existence in a kinetically limited competitive growth mode. 002 grains exhibit local cube-on-cube epitaxy with an orientation relationship (001) ScN ʈ (001) MgO and ͓010͔ ScN ʈ ͓010͔ MgO while 111 grains have a complex fourfold 90°-rotated in-plane preferred orientation in which strained ScN triangular ͕111͖ surface unit cells exhibit local epitaxy with square MgO unit cells yielding the orientation relationship (111) ScN ʈ (001) MgO , ͓110͔ ScN ʈ ͓110͔ MgO , and ͓112͔ ScN ʈ ͓110͔ MgO . Room-temperature electrical resistivity is 1.2 ϫ10 4 ⍀ cm while d/dT was found to be negative, indicating semiconducting behavior, with varying from 1.6ϫ10 4 ⍀ cm at 80 K to 1.1ϫ10 4 ⍀ cm at 400 K. Optical absorption coefficients ranged from 1ϫ10 4 cm Ϫ1 at 1.5 eV to 2.6ϫ10 5 cm Ϫ1 at 3.5 eV with a well-defined edge corresponding to a direct transition at 2.37Ϯ0.05 eV.

CeO2 films with thicknesses ranging from 8.8 to 199 nm were grown on Al2O3 (1102) (R-cut) substrates by off-axis rf magnetron sputtering. X-ray diffraction showed an epitaxial relationship with the CeO2 (001) planes parallel to the Al2O3 (1102) planes for all film thicknesses. Atomic force microscopy (AFM) revealed a rough surface morphology consisting of crystallites with lateral dimensions of 10–90 nm. In the thinnest film, these crystallites were regularly shaped and uniformly distributed on the substrate, while they were rectangularly shaped and oriented mainly in two directions, orthogonal to each other, in the thicker films. The surface roughness of the films increased with increasing layer thickness. Characterization of the microstructure was done by cross-sectional transmission electron microscopy (XTEM) and showed a polycrystalline, highly oriented, columnar structure with a top layer terminated by (111)-facets. High-quality YBa2Cu3O7−δ (YBCO) thin films were deposited directly onto the CeO2 layers. XTEM, rather surprisingly, showed a smooth interface between the YBCO and CeO2 layer. Postdeposition ex situ annealing was carried out on two CeO2 films and evaluated by AFM. Upon annealing samples at 930 °C, a relatively smooth morphology without facets was obtained. Annealing films at 800 °C caused no appreciable change in surface morphology, whereas igniting a YBCO plasma during a similar anneal clearly altered the sample surface, giving facets that were rounded.