https://doi.org/10.1051/epjap/2016160079
Regular Article
Potentiostatic controlled nucleation and growth modes of electrodeposited cobalt thin films on n-Si(1 1 1)
1
Université de Haute Alsace (UHA), Institut de Science des Matériaux de Mulhouse (IS2M), UMR 7361 du CNRS, 3b rue Alfred Werner, 68092 Mulhouse, France
2
Université d’Oran 1 Ahmed Benbella, Laboratoire de Physique des Couches Minces et Matériauxpour l’Electronique (LPC2ME), BP 1524, El M’Naouer, 31000 Oran, Algeria
a e-mail: jean-luc.bubendorff@uha.fr
Received:
22
February
2016
Revised:
6
July
2016
Accepted:
7
July
2016
Published online: 2 August 2016
The nucleation and growth of Co electrodeposits on n-Si(1 1 1) substrate have been investigated as a function of the applied potential in a large potential range using electrochemical techniques (voltammetry and chrono-amperometry) and surface imaging by atomic force microscopy (AFM). The surface preparation of the sample is crucial and we achieve a controlled n-Si(1 1 1) surface with mono-atomic steps and flat terraces. Using Scharifker-Hills models for fitting the current-time transients, we show that a transition from an instantaneous nucleation process to a progressive one occurs when the overpotential increases. A good agreement between the nucleation and growth parameters extracted from the models and the AFM data’s is observed. The growth is of the Volmer-Weber type with a roughness and a spatial extension in the substrate plane of the deposited islands that increase with thickness.
© EDP Sciences, 2016
