Additive effects during pulsed deposition of Cu-Co nanostructures

The effects of two additives, sudium dodecyl sulfate (SDS) and saccharin, o n 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 Go-rich columns sur rounded by a Cu-rich matrix phase. Films made with both SDS and saccharin a t short pulse periods are face-centered cubic in orientation with a grain s ize of about 10-15 nm. The interfacial planarity of laminated Films produce d at longer pulse periods is improved by saccharin. By taking advantage of the self-organizing Go-rich columns obtained at short pulse periods and usi ng Cu spacer layers, it is possible to obtain three-dimensional arrays of G o-rich nanophases using a single electrolyte and no masking of lithographic processes. (C) 2000 The Electrochemical Society. S0013-4651(99)12-105-0. A ll rights reserved.