Microstructure and electrical properties of chemical solution deposition (Pb,La)(Zr,Ti)O₃ thin films on Pt electrodes

Abstract

(Pb,La)(Zr,Ti)O3 (PLZT) films with thicknesses of 150 and 225 nm were prepared by the chemical solution deposition method on sputtered Pt/IrO2 coated on SiO2/Si wafers. The annealed films revealed two different microstructures: fined-grained and large-grained. The thinner film had the largest grain size and highest leakage current, whereas the thicker film had small grains and lower leakage. Atomic force microscope images showed that the thinner film had half-domed-shaped grains, which were about one-third thinner at the grain boundary triple points. These triple points also contained a nanocrystalline nonstoichiometric secondary phase, which contributed to high leakage. A model was developed showing differences in crystallization on the basis of grain growth and number of nuclei on the Pt surface. These results indicate the importance of controlling the film microstructure and its relationship to the film electrical properties.

METALLO-ORGANIC DECOMPOSITION SYNTHESIS AND CHARACTERIZATION OF FERROELECTRIC (PB1 −XCAX)TIO3 Thin Films

“…Improvement in the ferroelectric properties of PCT films with increase in Ca content is attributed to a combined effect of reduction in stress in the film, decrease in dielectric anisotropy (lower c/a ratio) and reduction in the grain size. Further, an increase in the Ca/Pb ratio also helps to minimize the loss of Pb and inhibits interfacial Pb-Pt intermetallic reaction with Pt electrode [31]. It may be recalled that XRD pattern of PCT50 was mostly pseudocubic.…”

Structure and dielectric properties of sol–gel 9/65/35 PLZT thin films

“…The decrease in the grain size with increase of film thickness was also observed in the case of sol-gel x/1.5/45/55 PLZT on Pt coated Si substrate. 15 The dielectric measurements of L6-1 sample revealed the typical relaxor behaviour (Fig. 3).…”

Growth and electrical properties of compositionally graded Pb(ZrxTi1−x)O3 thin films on PbZrO3 buffered Pt/Ti/SiO2/Si substrates

“…Zr-rich at the interface between the graded PZT films and Pt is due to the PbZrO 3 buffered Pt-coated silicon substrate. Because PbTiO 3 has a lower crystallization temperature than PbZrO 3 , as the annealing progresses the nuclei grow into a half-dome shapes pushing out excess Pb in front of the perovskite grain as well as some Zr and inclusions [13,15]. The relative concentrations of Zr and Ti as a function of depth for the graded PZT film can also be seen in Fig.…”

“…As indicated by the splitting of the (0 0 2)/(2 0 0) doublets, which suggests the presence of the tetragonal structure in the crystallized films. The nucleation mechanism of PZT (1 1 1)-orientation has been proposed to date in the literature [12,13,[15][16][17][18]. The proposed mechanism is that PZT(1 1 1) nucleates via a transient intermetallic phase such as Pt 5À7 Pb [17] and Pt 3 Pb [18].…”