Pseudo-epitaxial lead zirconate titanate thin film on silicon substrate with enhanced ferroelectric polarization

A pseudo-epitaxial Pb(Zr0.52Ti0.48)O3 (PZT) thin film was fabricated on a silicon substrate using a La0.7Sr0.3MnO3∕YBa2Cu3O7−δ∕yttria-stabilized zirconia heterostructure template by a pulsed-laser deposition process. The pseudo-epitaxial PZT thin film was characterized with broad x-ray diffraction peaks and granular morphology with nanometer-sized pores distributed across the film. Despite the imperfect epitaxial quality, the pseudo-epitaxial PZT thin film exhibited a substantially larger ferroelectric polarization than those “ideal” epitaxial films deposited on silicon substrates. The possible mechanisms underlying this phenomenon were analyzed, and the results indicated that only improving the epitaxial quality without considering the tensile stress relief is not sufficient in achieving the optimal ferroelectric polarization for a ferroelectric film on silicon substrate.