| Pacific Rim Symposium on Surfaces, Coatings and Interfaces (PacSurf 2016) | |
| Nanomaterials | Wednesday Sessions |
| Session NM-WeM |
| Session: | Nanocharacterization |
| Presenter: | Adam Hitchcock, McMaster University, Canada |
| Authors: | A.P. Hitchcock, McMaster University, Canada V. Prabu, McMaster University, Canada S.M. Rosendahl, Canadian Light Source, Canada M. Reynolds, Norcada Inc, Canada H. Hosseinkhannazer, Norcada Inc, Canada |
| Correspondent: | Click to Email |
We are using soft X-ray scanning transmission X-ray microscopy (STXM) [1] to investigate Cu thin film and dendritic electrochemical growth on a Au surface under variable pH conditions. Electrochemical reduction of Cu(II) under acid conditions is commonly used to deposit copper for integrated circuit interconnects, and in many other technologically important applications of thin films and nanoscale Cu metal. Improved understanding of the fundamental steps of the reaction and how to control undesirable phenomena such as dendritic growth is needed to further optimize this process. The reduction of Cu(II) to Cu(0) proceeds via a Cu(I) intermediate, which can be detected under weakly acidic to neutral conditions. We have developed a novel device for in situ STXM studies of electrochemical reactions which can operate under flow or static conditions [2]. The ability to change electrolyte during an experiment is being used to better understand the role of Cu(I) species in the deposition process. Spectromicroscopy at the Cu 2p and O 1s edges is used to analyze initial and final states, follow the process in situ, and search for intermediate species. The apparatus and techniques for spectro-electrochemical-microscopy will be described and results will be presented from deposition & stripping of copper from CuCl2(aq) and CuSO4(aq) electrolytic solutions as a function of pH.
STXM performed using BL10ID1 at CLS and BL 5.3.2.2 at ALS . Research supported by NSERC and the Catalyst Research for Polymer Electrolyte Fuel Cells (CaRPE-FC) network.
References
[1] A.P. Hitchcock, Soft X-ray Imaging and Spectromicroscopy in Handbook on Nanoscopy, eds.
G. Van Tendeloo, D. Van Dyck and S. J. Pennycook 2012. (Wiley)
[2] A.P. Hitchcock, Z. Qin, S.M. Rosendahl, V. Lee , M. Reynolds and H. Hosseinkhannazer, Electro-deposition of Cu studied with in situ electrochemical scanning transmission x-ray microscopy Am. Inst. Phys. Conf Series 1696 (2016) 02003 (1-5)