Preparation of Zr-rich PZT and La-doped PbTiO3 thin films by RF magnetron sputtering and their properties for pyroelectric applications

Zr-rich PZT and La-doped PT films were fabricated on a PLT/Pt/Ti/SiO2/Si or Pt/Ti/SiO2/Si substrate by an RF planar magnetron sputtering equipment using powder targets with compositions of PbZr0 94Ti0.06O3, PbZr0.92Ti0.08O3 and Pb0.85La0.15 Ti0.96O3 with excess PbO of 20 mol%. The dielectric constants of PZT and PLT films showed anomalies at the transition temperatures of around 246 and 300°C, and their dielectric constants at room temperature were 350 and 1070, respectively. Significant pytroelectric currents were observed in both as-grown PZT and PLT films even without a poling treatment. The pyroelectric coefficients of those films were 10 and 30 nC/cm2K, respectively. Therefore, Zr-rich PZT and [111]-oriented PLT films sputtered on Pt/Ti/SiO2/Si substrates possess desirable properties for potential applications to pyroelectric devices.