Epitaxial Single‐Crystalline PZT Thin Films on ZrO₂‐Buffered Si Wafers Fabricated Using Spin‐Coating for Mass‐Produced Memristor Devices

Abstract

A Pb(Zr0.52Ti0.48)O3 (PZT) thin film is fabricated on SrRuO3(SRO)/Pt/ZrO2/Si, and its resistive switching properties are thoroughly investigated. The ZrO2 thin film serves as a buffer layer for the epitaxial growth of single‐crystalline PZT thin films, and spin‐coating fabrication is useful for introducing a suitable defect content to achieve effective resistive switching in PZT. The present PZT thin film exhibits improved ferroelectric properties compared with most of the spin‐coated or sol‐gel prepared PZT films reported previously, with a large saturation polarization of ≈43 µC cm−2 and coercive filed of ≈700 kV cm−1. The symmetrically reversed true‐remanent hysteresis shows no evident imprint effect and a fully saturated polarization is observed. Intrinsic ferroelectric properties indicate the presence of non‐switching components that are conducive to memory applications. Butterfly shaped electrical conduction reveals resistive switching behavior, with abnormal bipolar resistive switching (BRS) at low voltages and normal BRS at high voltages. The abnormal BRS is explained by a microscopic mechanism involving ferroelectric polarization and an induced dipole moment, whereas the normal BRS is studied by fitting different conducting models and is dominated by interfacial barriers and defects. This study presents a progressive strategy for the large‐scale production of ferroelectric perovskite thin films, specifically suitable for silicon‐based memristors.