Influence of doping and buffer layers on Pb(Zr,Ti)O3 thin films derived from inorganic zirconium precursor

The effects of doping and buffer layers on the structure and electrical properties of Pb(Zr,Ti)O3 (PZT) thin films on Pt/TiO2/SiO2/Si substrate derived from inorganic zirconium precursor have been studied. Ta doping optimizes the structure texture and reduces the leakage current of PZT films, whereas Ce-doped films have large amount of pyrochlor phase formed and a large leakage current. Dielectric measurement indicates that Ce and Ta doping can greatly change the dielectric constant of films. Doped and undoped PZT films exhibit an ohmic-like current even at high field. PbTiO3 (PT) and LaNiO3 (LNO) were used as PZT buffer layers on Pt/TiO2/SiO2/Si substrate. XRD patterns show that PT buffer layers can decrease the crystallization temperature of PZT films (by about 50 °C). No pyrochlor phase was detected in PZT/PT and PZT/LNO films. Additionally, PZT/LNO films exhibit good fatigue characteristics compared with films directly deposited on Pt-coated Si substrate.