Structure and dielectric properties of 80%Pb(Zn1/3Nb2/3)O3–20%PbTiO3 thin films prepared by modified sol–gel process

Abstract

80%Pb(Zn1/3Nb2/3)O3–20%PbTiO3 (PZN–PT) thin films have been prepared on Pt/Ti/SiO2/Si substrates using a modified sol–gel method. In our method, niobium pentaoxide is used as a substitution instead of niobium ethoxide which is moisture-sensitivity and much more expensive. Microstructure and electrical properties of PZN–PT thin films have been investigated. X-ray diffraction analysis shows that proper annealing temperature of PZN–PT thin films is 600 °C. The PZN–PT thin films annealed at 600 °C are polycrystalline with (111)-preferential orientations. Field-emissiom scanning electron microscope analysis revealed PZN–PT thin films possess well-defined and crack-free microstructure. The thickness of thin films is 290 nm. The Pt/PZN–PT/Pt capacitors have been fabricated and it presents ferroelectric nature. The remanent polarization (Pr), spontaneous polarization (Ps), and the coercive electric field (Ec) are 8.71 μC/cm2, 43.06 μC/cm2, and 109 kV/cm at 1 MHz, respectively. The dielectric constant (er) and the dissipation factor (tan δ) are about 500.3 and 0.1 at 1 kHz, respectively.