Evolution of the Morphology of Electrodeposited Copper at the Early Stage of Dendritic Growth

The morphological evolution at the onset of dendritic growth of Cu electrodeposited from unsupported CuSO 4 solution under high current density was observed by Scanning Electron Microscopy (SEM). SEM observation was conducted for three stages of the Cu electrodeposition process; i) just before, ii) at and iii) soon after depletion of the Cu 2+ ion at the cathode surface. A deposit consisting in microcrystals was observed at all stages, with size ranging from 20 nm to 2 μm. This size was shown to increase with Cu concentration and decrease with overpotential. At stage iii) the early stage of dendritic growth was observed.