X-ray diffraction data for 400 nm films of Cu, Cu-Ni, and Ni, deposited without seed layer, after annealing at and 270 Pa (2 Torr). (a) curves, plotted on a logarithmic intensity scale, show that all films are exclusively (111) textured. (b) Rocking curves with Gaussian fits yielding full-width-at-half-maximum of 0.334° for Cu, 0.533° for Cu-Ni, and 0.393° for Ni. (c)–(e) (111) pole figures plotted on a logarithmic color scale. The six innermost spots come from the substrate and the other spots come from the metal film. The six outer spots of roughly equal intensity indicate each film contains two families of (111) grains differing by an in-plane rotation of .
Optical and atomic force microscopy images showing the morphology of the same films as in Fig. 1. Top row ((a)–(c)) shows optical images ( scale bar, shown in (c)) and bottom row ((d)–(f)) shows AFM images ( scale bar, shown in (f)) Dark spots in the optical images indicate areas of dewetting. The Cu surface becomes rough, while the Ni surface remains much smoother.
Electron backscatter diffraction data for the same films as in Fig. 1 and for a polycrystalline Ni foil. (a)–(c) Orientation maps using a color scale that represents in-plane direction only: blue and green regions differ by . The scale bar shown in (c) is . (e)–(g) (111) pole figures with a logarithmic color scale. The Cu film shows equal amounts of each orientation, while the Cu-Ni and Ni films show a majority of one orientation in the regions shown. (d) Orientation map for a polycrystalline Ni foil after annealing to . Wedge color scale represents out-of-plane orientation. Scale bar is . (h) (111) pole figure for the polycrystalline Ni foil.
Crystallinity and morphology of 400 nm Ni film deposited with seed layer, after annealing at and 270 Pa (2 Torr). Optical image in (a) and EBSD map in (b) ( scale bars) show fewer grains than the corresponding images for Ni without the seed layer (Figs. 2(c) and 3(c), respectively). AFM image in (c) shows an ordered surface and shallower trenches between grains than in Fig. 2(f) ( scale bar). XRD (111) pole figure in (d), plotted on a logarithmic intensity scale, shows a single in-plane orientation over 97% of the film. Line profile in (e), taken along the black line in (c), shows steps wide and high.
Cross-sectional transmission electron microscopy of Ni on . (a, b) Without seed layer. (c, d, e) With seed layer. In (a), a twin boundary in the Ni is seen at the edge of an extra (0003) lattice fringe that may indicate a dislocation or step at the surface. The focused probe diffraction pattern corresponding to the region of the Ni twin boundary is shown in (b), where the subscript “T” labels spots from one of the twin grains. In (c), the lattice fringes of the film with the seed layer are continuous and smooth, indicating the surface was not damaged by the resputtering process. Selected area diffraction patterns are shown for the Ni in (d) and for the in (e).
SEM images of multilayer graphene grown on Ni films. ((a), (c), (e)) 400 nm epitaxial Ni(111) on . ((b), (d)) 400 nm polycrystalline Ni on . Scale bars are for (a) and (b), for (c) and (d), and for (e). (f) Raman spectroscopy indicates there is at least a monolayer of graphene at all points. Darker regions correspond to thicker growth.
RMS roughness of metal films on under different annealing conditions. Annealing time was 15 min in all cases. All roughness values were measured from a AFM image.
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