Dynamics of an electrolyte-n-type silicon system during anodization in hydrofluoric acid solutions

The dynamics of the morphology of porous silicon during anodization in hydrofluoric acid has been investigated. The current-voltage characteristics and their variation with time as well as the time dependence of the voltage in an electrolyte-silicon system are highly informative for the construction of a general theory of pore formation in silicon. Attention is drawn to the possible existence of a bifurcation in the transition to harmonic oscillations of U(t) in the course of anodization. In this case, the laws governing the pore formation processes before and after the bifurcation will obviously differ.