One of the essential criteria for the material evaluation for high speed applications such as ferroelectric memories is the switching speed as a function of the applied field. Theoretically the kinetics of switching in bulk and films have often been modeled using models derived from the Kolmogorov Avrami theory. Because some important aspects of thin films are not possible to take into account within this framework, we have adopted another approach based of a time-dependent Ginzburg-Landau model. The present work is devoted to investigating the influence of the surface effect and the bound charges field on the switching properties.