Communication—Electrochemical Atomic Layer Etching of Copper. Issue 7 (9th May 2018)

• Record Type: Journal Article
• Authors: Gong, Yukun; Venkatraman, Kailash; Akolkar, Rohan
• Is Part Of: Journal of the Electrochemical Society. Volume 165:Issue 7(2018)
• Page Start: D282
• Page End: D284
• Publication Date: 2018-05-09
• Subjects: atomic layer etching -- selective etching -- sulfidization; Electrochemistry -- Periodicals; 541.3705
• DOI: 10.1149/2.0901807jes
• Languages: English
• ISSNs: 0013-4651

Abstract

Abstract : A novel process for the electrochemical atomic layer etching (e–ALE) of copper (Cu) is presented. In this process, Cu first undergoes surface-limited sulfidization to form a monolayer of copper sulfide (Cu2 S). The Cu2 S layer is then selectively etched in hydrochloric acid without etching the underlying Cu. The steps of surface-limited sulfidization of Cu and selective etching of the resulting Cu2 S are repeated sequentially to achieve a net etch rate of close to one Cu monolayer etched per e–ALE cycle. Surface-limited etching is shown to minimize roughness amplification thereby preserving the near-atomic flatness of the original Cu electrode.