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A novel process for the electrochemical atomic layer etching (e-ALE) of ruthenium (Ru) is described. In this process, the surface Ru is electrochemically oxidized to form a monolayer of ruthenium (III) hydroxide—Ru(OH)3. The Ru(OH)3monolayer is then selectively etched in an electrolyte containing chloride (Cl–) species. This etching process is selective towards Ru(OH)3and does not attack the underlying Ru metal. Adsorbed Cl–on the Ru electrode is then cathodically desorbed before the sequence of Ru oxidation and Ru(OH)3etching is repeated. This e-ALE sequence is shown to etch Ru at approximately 0.5 monolayer per cycle while practically avoiding any surface roughness amplification. The proposed Ru e-ALE process uses a single electrolyte which eliminates the need for electrode transfer or electrolyte switching between process steps. In this report, we employ electrochemical, microscopic and spectroscopic techniques to gain insights into the various characteristics of the Ru e-ALE process.
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This content will become publicly available on June 1, 2026
Low temperature XPS of (η4-cyclooctatetraene)Ru(CO)3
X-ray photoelectron spectroscopy was used to analyze an authentic sample of (η4-cyclooctatetraene)Ru(CO)3 held at 173 K to prevent sublimation of the compound during measurement. This precursor has previously shown utility for photoassisted chemical vapor deposition of Ru species onto alkanethiolate self-assembled monolayers. Herein, we report that the Ru signals for the Ru(0) complex are at a higher binding energy than those of pure Ru metal.
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- PAR ID:
- 10630165
- Publisher / Repository:
- AVS
- Date Published:
- Journal Name:
- Surface Science Spectra
- Volume:
- 32
- Issue:
- 1
- ISSN:
- 1055-5269
- Page Range / eLocation ID:
- 014008
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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