Electrochemical growth of single copper crystals on glassy carbon and tungsten substrates is studied by measuring the time dependence of the crystals' radius R(t) under potentiostatic conditions. The obtained results are interpreted in terms of a theory accounting for pure charger transfer and combined charge transfer and diffusion limitations. The values of three important growth parameters, the diffusion coefficient, the exchange current density and the charge transfer coefficient are experimentally determined. Information is obtained on the stationary nucleation rate of copper clusters on the tungsten substrate. (c) 2007 Elsevier B.V. All rights reserved.