Current oscillations in the anodic dissolution of silicon: On the origin of a sustained oscillation on the macroscopic scale

The damped current oscillations observed in the anodic dissolution of silicon in fluoride electrolyte have been attributed to a sustained current oscillation on the local scale. However, the possibility of a sustained oscillation on the macroscopic scale has been a subject of controversy. Here, through a combined simulation/analytical probabilistic analysis, we examine whether an interaction between the various locations on the electrode surface may lead to a macroscopic oscillation of the total current. We find that a short-range interaction cannot lead to a synchronisation of the oscillation over the surface of a large electrode. Such a synchronisation might however be obtained on small electrodes, or with appropriate values of the system parameters. The examination of existing data in the literature rather points to a macroscopic oscillation induced by global coupling through extrinsic resistances in series with the electrode.