Investigation On Preparation And Electrical Properties Of PZT Thin Films

Ferroelectric materials have excellent piezoelectric, ferroelectric and pyroelectric properties; it received widespread attention in recent years. Among these, Lead zirconate titanate （PZT） is a perovskite structure ferroelectric material with excellent piezoelectric, ferroelectric and pyroelectric properties, and these properties can be improved by changing the ratio of Zr/Ti and doping. PZT films have been widely used in ferroelectric random access memory （FRAM）, surface acoustic wave （SAW） devices and infrared detectors. The Zr-rich （Zr>90mol%） PZT films have rich phase changes and large spontaneous polarization, the dielectric constant （ε） and dielectric loss （tanδ） are low when the phase changes happen; so it can be used in infrared detection hopefully.In this paper, the preparation processes of pulsed laser deposition （PLD）, micro-structures, ferroelectric and pyroelectric properties of Pb(Zr_0.93Ti_0.07)O₃ films were Investigated. The Ag/PZT/YBCO/Si thin films were prepared by PLD. Si was the substrate; Ag and YBCO were the top electrode and the bottom electrode respectively. The influences of preparation processes on micro-structures, ferroelectric and pyroelectric properties of PZT films were investigated after these properties had been tested. The results showed that, PZT films prepared in the optimized conditions had excellent micro-structures, ferroelectric and pyroelectric properties. The peak value of pyroelectric coefficient （p） in the room temperature and curie temperature were 0.9μC/（cm²·K） and 47μC/（cm²·K） respectively. The PZT thin films showed excellent pyroelectric properties, and could potentially be used in infrared detection.