Preparation of ferroelectric PZT thin films by plasma enhanced chemical vapor deposition using metalorganic precursors

The low temperature and non-thermal equilibrium process is the major advantage of plasma enhanced chemical vapor deposition (PECVD) method for thin film deposition. In this study, the preparation of lead zirconate titanate (PZT) thin films by PECVD has been evaluated. As-deposited PZT thin films prepared via PECVD with Pb(C2H5)4, Ti(O-i-C3H7)4 and Zr(O-i-C4H9)4 source had an amorphous phase and transformed into a crystalline structure from the annealing temperature of around 500 °C under an oxygen ambient. Change of Pb content in the film did not occur under a wide range of annealing temperatures and times, but the surface morphology became coarser with an increase of Pb content. The dielectric constant was strongly affected by the PZT film thickness. Typically the dielectric constant of PZT (Zr/Ti = 54/46) film was 572 at a thickness of 240 nm. Additionally, the film had a remnant polarization, 2Pr,of 42 μC/cm2 and a coercive filed, Er, of 88 kV/cm.