Additive Effects during Pulsed Deposition of Cu-Co Nanostructures

The effects of two additives, sodium dodecyl sulfate (SDS) and saccharin, on the composition and microstructure of pulse‐plated Cu‐Co alloys have been studied. The additive SDS appears to promote the displacement of Co by Cu during pulse off‐times in the pulsed deposition of Cu‐Co alloys. For short pulse periods, films made with SDS only are composed of Co‐rich columns surrounded by a Cu‐rich matrix phase. Films made with both SDS and saccharin at short pulse periods are face‐centered cubic in orientation with a grain size of about 10–15 nm. The interfacial planarity of laminated films produced at longer pulse periods is improved by saccharin. By taking advantage of the self‐organizing Co‐rich columns obtained at short pulse periods and using Cu spacer layers, it is possible to obtain three‐dimensional arrays of Co‐rich nanophases using a single electrolyte and no masking of lithographic processes. © 2000 The Electrochemical Society. All rights reserved.