Electrodeposition of Ru onto Ru and Au Seed Layers from Solutions of Ruthenium Nitrosyl Sulfate and Ruthenium Chloride

The electrodeposition of Ru was investigated from solutions of ruthenium(III) nitrosyl sulfate and ruthenium(III) chloride onto seed layers of epitaxial and polycrystalline Ru and epitaxial Au. Using both galvanostatic and potentiostatic deposition modes, metallic Ru was found to electrodeposit as a porous layer comprised of (0001) oriented Ru crystallites, the presence of which was discovered and confirmed by X-ray and scanning transmission and transmission electron microscope (S/TEM) analyses. This finding was independent of the Ru salt and seed layer used. Using X-ray reflectivity (XRR), the average film density$ρeff$of the porous electrodeposited Ru layer was measured as less than the density of bulk Ru$ρRu,bulk$(14.414 g cm−3). Increasing the magnitude of the applied current density from −100μA cm−2to −10 mA cm−2in solutions of Ru nitrosyl sulfate increased the$ρeff$from 7.4 g cm−3to 9.7 g cm−2while the current efficiency decreased from 9.4% to 4.3%.

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Publication Date:
NSF-PAR ID:
10361798
Journal Name:
Journal of The Electrochemical Society
Volume:
168
Issue:
5
Page Range or eLocation-ID:
Article No. 052504
ISSN:
0013-4651
Publisher:
The Electrochemical Society
National Science Foundation
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