Effect of Pb1.1(Al1/2Nb1/2)O3 on Structure and Electrical Properties of Lead Titanate Thin Films Prepared by Chemical Solution Deposition Process

Abstract

A series of Pb1.1(Al1/2Nb1/2)O3–Pb1.1TiO3 [xPAlN–(1-x)PT, x=0, 0.1, 0.2, 0.25, 0.3, 0.4, 0.5, 0.7, 1] thin films of 400–500 nm thickness were fabricated successfully onto Pt(111)/Ti/SiO2/Si substrates using a chemical solution deposition (CSD) process. The thin films consisted of a single perovskite phase when the PAlN content was less than 25 mol%, whereas pyrochlore-type phases were observed in the thin films containing more than 30 mol% PAlN. This result indicates that the solubility limit of PAlN in the perovskite phase is 25 mol%. Among the single perovskite xPAlN–(1-x)PT phase, the 0.2PAlN–0.8PT thin film showed a maximum dielectric constant of approximately 600, and a slim P–E hysteresis loop. The remanent polarization (Pr) and the coercive field (Ec) of this thin film were 12 µC/cm2 and 38 kV/cm, respectively. The leakage property of the xPAlN–(1-x)PT thin films showed a tendency to decrease with increasing amount of PAlN added. The xPAlN–(1-x)PT thin films containing more than 20 mol% PAlN showed less than 10-7 A/cm2 current density at ±150 kV/cm, and were superior in terms of the leakage property of the Pb(Zr, Ti)O3 thin film.