The investigation of Pb(ZrTi)O-3 (PZT) etching mechanism in both Cl-2/Ar and CF4/Ar plasmas was carried out. It was found that, in CF4/ Ar plasma, etch rate has a maximum at 80% Ar, while for Cl-2/Ar plasma, etch rate keeps a constant value up to 40% Ar. The volume densities and fluxes of active species in both gas mixtures derived from the zero-dimensional (0-D) plasma models change in same manner while a nonmonotonic behavior was not observed. However, the analysis of surface kinetics confirmed the possibilities of nonmonotonic etch rate behavior in both gas mixtures due to a concurrence of physical and chemical pathways in ion-assisted chemical reaction. (C) 2004 Elsevier B.V. All rights reserved.