Lanthanum-modified lead zirconate titanate (PLZT) thin films were fabricated by electron cyclotron resonance plasma enhanced chemical vapor deposition (ECR-PECVD) using MO sources. The composition of the PLZT films could be controlled by varying the flow rate of each MO source. Perovskite PLZT thin films with a smooth surface and fine grains were successfully fabricated on Pt/Ti/SiO2/Si at 450 degrees C. The deposition mechanism of the PLZT films in the ECR plasma was studied by examining the rate of incorporation of each cation into the film at various MO source flow rates. The microstructure of the deposited films and RTA treatment effects were also evaluated.