Influence of sputtering and annealing conditions on the structure and ferroelectric properties of Pb(ZrTi)O-3 thin films prepared by RF magnetron sputtering

Lead zirconate titanate (PZT) thin films were prepared on Pt/Ti/Corning 705 9 glass substrates by RF magnetron sputtering using a Pb(Zr-0.5,Ti-0.5)O-3 ceramic target. X-ray diffraction studies were performed on the films to op timize the sputtering pressure, O-2/(Ar+O-2) mixing ratio (OMR), annealing temperature and annealing time, to prepare the films in the perovskite phas e. As-deposited amorphous film goes through an intermediate pyrochlore phas e before crystallizing in the perovskite phase. Perovskite phase formation started at 625 degreesC and annealing at 650 degreesC for 2 h was found to be necessary for complete crystallization in the single perovskite phase. P erovskite phase formation was confirmed with the existence of a perovskite rosette structure by scanning electron micrograph (SEM). Energy dispersive X-ray (EDX) compositional analysis of as-deposited films showed Pb/(Zr+Ti) similar or equal to 1.1; a 10% deviation from the target stoichiometry. Fer roelectric and dielectric properties of the capacitor with thin platinum fi lms as both electrodes were investigated in detail as functions of annealin g temperature and annealing time. The marked improvement in the structural and electrical properties observed in the deposited film after annealing wa s mainly due to the crystal growth of small crystallites. The dielectric co nstant and loss tangent of the films annealed at 650 degreesC for 2 h were 580 and 0.06, respectively. The films with 1.4 mum thickness that were anne aled at 650 degreesC showed a remanent polarization (P-r) = 26 muC/cm(2) an d coercive field (E-c) = 51 kV/cm.