Effects of substantial atomic-oxygen migration across silver − oxide interfaces during silver growth

• Published in: Applied surface science 2021-12, Vol.568, p.150927, Article 150927
• Main Authors: Jeong, Eunwook, Lee, Sang-Geul, Bae, Jong-Seong, Yu, Seung Min, Han, Seung Zeon, Lee, Gun-Hwan, Choi, Eun-Ae, Yun, Jungheum
• Format: Article
• Language: English
• Subjects: Atomic oxygen; Density functional theory; Migration; Wetting
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/j.apsusc.2021.150927

We present experimental evidence, supported by numerical predictions, to demonstrate the substantial migration of excessive atomic oxygen from ZnO substrates to Ag lattices across ZnO−Ag interfaces, which induces an increase in the adhesion and wetting of Ag on ZnO substrates. [Display omitted] •Solid evidence supports substantial O intermixing in Ag − ZnO matrices.•Excess atomic O dissolved in ZnO surfaces migrates across Ag − ZnO interfaces.•O incorporated in Ag interstitials participates in formation of Ag oxides.•O intermixing lowers the free energy at Ag − ZnO interfaces.•O intermixing eventually increases Ag adhesion and wetting on ZnO surfaces. The optimization of Ag wetting on oxides is essential to facilitate the synthesis of ultrathin Ag layers with ultralow electrical and optical losses. However, the primary challenge of increasing the Ag wetting on oxides is the strong cohesion and weak adhesion of Ag with chemically heterogeneous oxide substrates. In the present study, it was observed that the dissolution of excess atomic oxygen in ZnO lattices prior to Ag deposition induced the pronounced migration of atomic oxygen across the Ag − ZnO interface and subsequent incorporation into Ag lattices. The substantial intermixing of atomic oxygen in the Ag − ZnO matrices contributed to a decrease in the free energy at the interface, thereby weakening the driving force for the agglomeration of Ag nanoparticles during coalescence. This resulted in an increase in the adhesion and wetting of Ag geometries on the ZnO surfaces. These findings were confirmed based on the results of detailed experimental investigations in conjunction with numerical predictions. These outcomes elucidated the unconventional oxygen spillover dynamics from atomic oxygen-excess oxide surfaces. The findings obtained in the present study refute the existing convictions that the intermixing of oxygen at Ag − oxide interfaces is limited by weak charge transfer.