Increased Fatigue Endurance in Pb(Zr,Ti)O3 Thin Films through Use of PbZrO3 Buffer Layers

Abstract

Thin PbZrO3 (PZ) films were investigated as a buffer layer to improve fatigue endurance of Pb(Zr0.45Ti0.55)O3 (PZT) thin films. The PZ thin films were deposited on Pt(111)/Ti/SiO2/Si(100) substrates by RF magnetron sputtering from a loose powder target containing a mixture of PbZrO3 and ZrO2 powders. The PZT thin films on the PZ buffer layer were obtained by sol–gel spin coating. The PZ buffered PZT films had well crystallized, uniform and dense microstructure with partial (111) orientation. The P–E hysteresis measurements indicated comparable or slightly lower remnant polarization values (2Pr=50–70 µC/cm2) and higher coercive field levels compared to unbuffered film (2Pr=66 µC/cm2). The PZ buffered films displayed an asymmetric leakage current. The fatigue endurance of PZT thin films with PZ buffer layers was superior compared to the unbuffered counterpart with fatigue-free behavior observed up to 109 switching cycles.