Implication of low temperature and sonication on electrocrystallization mechanism of Cu thin films: a kinetics and structural correlation

摘要

The effect of an ultrasonic environment during electrodeposition of copper on graphite at various electrolyte temperatures of 25, 20, 15, 10 and 5 °C is reported in this investigation. Resulting Cu deposits formed by potentiostatic deposition were characterized by electrochemical methods, scanning electron microscopy and atomic force microscopy. It was found that in presence of ultrasound the deposition kinetics was mainly dominated by the charge transfer. Copper nucleated according to 3D instantaneous mechanisms for all temperature ranges. The extent of nucleation was found to be increased at low temperatures. Diffusion coefficients and nuclei population density were calculated for each temperature range. Sonicated deposits with good surface coverage were found to consist of spherical copper agglomerates of nanosized particles.