Effect of SrTiO3 seed layer deposition time and thickness on low-temperature crystallization and electrical properties of Pb(Zr, Ti)O3 films by metalorganic chemical vapor deposition

The effect of SrTiO3 seed layer thickness on low-temperature crystallization and electrical properties Pb(Zr, Ti)O3 (PZT) films by metalorganic chemical vapor deposition (MOCVD) were investigated. The thicknesses of SrTiO3 seeds were varied with 1-18 nm by deposition time. The preferred (1 1 1) PZT films could be obtained at 304 °C on SrTiO3 seeds prepared at 500 °C. The intensity of (1 1 1) PZT phase was increased with deposition time due to the enhancement of coverage of SrTiO3 seeds on substrate. The AFM observation revealed that the growth of PZT films was initially started on SrTiO3 seeds. The remanent polarization (2Pr) and leakage current density were changed with seed layer thickness. It is considered that concentration of the electric field on SrTiO3 seeds with capacitance changes were affected to electrical properties of PZT films. The 100 nm thick PZT films on 5 nm thick SrTiO3 seeds showed 2Pr max (18 μC/cm2) with 10−6 A/cm2 of leakage current density.