An electrochemical analysis of thin silver films produced by reactive sputtering

• Published in: Journal of the Electrochemical Society 2001-03, Vol.148 (3), p.C191-C196
• Main Authors: DJOKIC, S. S, BURRELL, R. E, LE, N, FIELD, D. J
• Format: Article
• Language: English
• Subjects: Cross-disciplinary physics: materials science; rheology; Deposition by sputtering; Exact sciences and technology; Materials science; Methods of deposition of films and coatings; film growth and epitaxy; Physics
• ISSN: 0013-4651; 1945-7111
• DOI: 10.1149/1.1346609

Silver films produced under conditions of reactive sputtering (a mixture of argon and oxygen atmosphere) were investigated. For this purpose. X-ray diffraction (XRD), scanning electron microscopy, and electrochemical methods were used. The results show that these films contain oxidized silver species (Ag sub 2 O and Ag sub 2 CO sub 3 ) and metallic silver. The size of silver crystallites increased from 4 to 40 nm as the amount of oxygen decreased from 10 to 0 vol % in the sputtering atmosphere and the amount of oxidized species in sputtered silver films increased as the amount of oxygen increased; this was confirmed by the XRD, chemical, and electrochemical analyses. In the first sweep of cyclic voltammograms, two anodic and one cathodic peaks appeared. Both anodic peaks are attributed to the oxidation of metallic silver and formation of Ag(I) species. The cathodic peak is attributed to the reduction of Ag(l) species produced during the anodic cycle as well as those existing in the sputtered silver films. Due to an increased roughness and porosity, in the second and in every successive sweep of cyclic voltammetry experiments, only one anodic and one cathodic peak appeared, which provides evidence for complete oxidation and/or reduction of the whole sputtered silver layer on the glass substrate.