Preparation and ferroelectric properties of (124)-oriented SrBi4Ti4O15 ferroelectric thin film on (110)-oriented LaNiO3 electrode

TL;DR

This study successfully prepared a highly oriented SrBi4Ti4O15 ferroelectric thin film on LaNiO3 electrodes, demonstrating excellent ferroelectric properties, durability over many switching cycles, and potential for large-area applications.

Contribution

It reports the fabrication of a (124)-oriented SBTi ferroelectric film with high volume fraction and long-term stability using a low-temperature process and proposes a long-range epitaxial relationship.

Findings

High remanent polarization of 12.1 μC/cm²

No fatigue observed after 1 billion cycles

Uniform polarization over large areas

Abstract

A (124)-oriented SrBi4Ti4O15 (SBTi) ferroelectric thin film with high volume fraction of {\alpha}SBTi(124)=97% was obtained using a metal organic decomposition process on SiO2/Si substrate coated by (110)-oriented LaNiO3 (LNO) thin film. The remanent polarization and coercive field for (124)-oriented SBTi film are 12.1 {\mu}C/cm2 and 74 kV/cm, respectively. No evident fatigue of (124)-oriented SBTi thin film can be observed after 1{\times}10e9 switching cycles. Besides, the (124)-oriented SBTi film can be uniformly polarized over large areas using a piezoelectric-mode atomic force microscope. Considering that the annealing temperature was 650{\deg}C and the thickness of each deposited layer was merely 30 nm, a long-range epitaxial relationship between SBTi(124) and LNO(110) facets was proposed. The epitaxial relationship was demonstrated based on the crystal structures of SBTi and LNO.