Tribology Online (Apr 2008)
Selective Growth of Homo-Epitaxial Ag-Nano-Layer on Tribo-Assisted-Reorientation
Abstract
The growth process and orientational degree of incremental-Ag films with a thickness of 5, 50 and 500 nm, respectively, on reoriented Ag (111) surface were studied by in-situ reflection high-energy electron diffraction (RHEED). The orientation of Ag grains for each incremental-Ag-film was also analyzed by synchrotron-orbital-radiated X-ray diffraction (SOR-XRD) to clarify the correlation between the film orientation and the incremental thickness by additional Ag deposition. RHEED observations showed that the incremental-Ag-film grows epitaxially on the reoriented-Ag (111) surface up to 500 nm in thickness. The Ag film, which grew on initial polycrystalline-Ag film, still showed a polycrystalline structure up to 50 nm in thickness, and the Ag (111) orientation is dominant at a thickness of 500 nm. The results of SOR-XRD analysis agreed well with those of RHEED. SOR-XRD analysis showed that the growth rate of Ag {111} grains in the polycrystalline film was also superior to that of other Ag {hkl} grains as the thickness increases. The degree of incremental film orientation increased as the incremental thickness increased, and the advantage in the high orientational degree of the incremental film on the reoriented Ag (111) surface was enhanced when the incremental thickness was within the nanometric range. A new method for selective growth of the epitaxial Ag layer using tribo-assisted reorientation was presented.
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