AFM imaging of copper stripping/deposition processes in selected electrolytes on boron-doped diamond thin-film electrodes

Electrochemical atomic force microscopy (EC AFM) studies of copper strippin g/deposition processes under potentiostatic control were carried out on bor on doped diamond thin-film electrodes in solutions of different ability to form copper complexes. Careful analysis of the electrode surface profiles t aken at the potentials switched between oxidative and reductive values reve als the nucleation state and the early stages of complex formation when cat ions are released from the deposited metal. An unusual increase of the depo sit-layer thickness is observed in sulfate- and phosphate-solutions at the positive potentials in contrast to an expected decrease of the surface adla yer thickness accompanying its stripping. The last effect takes place in th e case of copper stripping in the presence of nitrates when no complex is f ormed. Similar behavior is observed on the HOPG electrode used in these stu dies as a reference surface. (C) 2000 Elsevier Science Ltd. All rights rese rved.