Influence of deposition power on the composition, structure and properties of PZT thin films prepared by RF sputtering

PbZr_0.52Ti_0.48O₃(PZT) ferroelectric thin films were deposited on LaNiO₃ coated p-Si(111) substrates by RF magnetron sputtering at the low substrate temperature of 370°C with deposition power ranging from 60 W to 120 W, sequentially followed by a rapid thermal annealing process at 650°C for 5 minutes. The crystalline phase, microstructure, composition and electric properties of PZT thin films were investigated by X-ray diffraction, scanning electron microscopy, inductively coupled plasma-atom emission spectrometry, four-probe meter and spectroellipsometer respectively. It is found that the microstructure, composition and electric properties of sputtered PZT thin films are highly dependent on the deposition power, i.e., the atom rate Pb(Zr+Ti) of PZT films and the leakage current of Pt/PZT/LNO capacitors increase as the deposition power increases. Films deposited at low power are Pb-poor without ferroelectricity, while those deposited at high power are Pb-rich. Optimized deposition power is 80 W.