Abstract
La-doped lead zirconate titanate (PLZT) thin films were fabricated on Pt/Ti/SiO2/Si substrates by electron cyclotron resonance plasma-enhanced chemical vapor deposition (ECR-PECVD) method. The composition and the electrical properties of the films were investigated as a function of deposition temperature and Pb-source flow rate. Stoichiometric film with pure perovskite structure was fabricated at a deposition temperature as low as 450°C. As the deposition temperature was increased, the vapor pressure of lead oxide molecules increased and thus the PLZT film tended to be Pb-deficient, resulting in the formation of a non-perovskite phase and the degradation of electrical properties. This problem could be relieved by increasing the Pb-source flow rate. Rapid thermal annealing (RTA) greatly enhanced the electrical properties of the PLZT film as long as the as-deposited film had stoichiometric composition and pure perovskite structure. The rapid thermal annealed PLZT film (74 nm thick) had an effective charge density of 150 fF/µm2, dielectric constant of 1216 and SiO2 equivalent thickness of 0.24 nm.