Overcoming Size Effects in Ferroelectric Thin Films

• Published in: Advanced Physics Research Vol. 2; no. 6
• Main Authors: Park, Sung Hyuk, Kim, Jae Young, Song, Jae Yong, Jang, Ho Won
• Format: Journal Article
• Language: English
• Published: Edinburgh John Wiley & Sons, Inc 01.06.2023; Wiley-VCH
• Subjects: 2D ferroelectrics; Electric fields; Electrodes; Electronic circuits; Energy; ferroelectric; Ferroelectric materials; Ferroelectricity; Ferroelectrics; Fluorite; Grain size; Interfaces; Nanowires; perovskite oxide; Perovskites; Phase transitions; Physics; Random access memory; size effect; Size effects; Thickness; Thin films
• ISSN: 2751-1200; 2751-1200
• DOI: 10.1002/apxr.202200096

Ferroelectric thin films have recently received unprecedented attention due to the need to miniaturize electronic circuit devices. Synthesis and deposition processes along with theoretical calculations are improved remarkably to realize stable ferroelectric thin films up to nanometer thickness. However, even with technological advances, it is still difficult to overcome the size effect of ferroelectrics, so research is being conducted to achieve stable ferroelectricity in unit‐cell thicknesses thinner than the typical critical thicknesses. In this review, the size effects in ferroelectric thin films are described, and their importance and fundamental limitations are discussed. First, intrinsic and extrinsic factors affecting ferroelectricity are introduced based on the theoretical background of the size effects in ferroelectricity. Then, on understanding the size effects by considering complex interacting factors, the recent works showing ferroelectricity below the commonly known critical thicknesses in perovskite, fluorite oxides, and two‐dimensional (2D) ferroelectrics are introduced. Finally, the results of research efforts in scaling ferroelectric thin films with a future perspective are summarized. Continuous research is done to demonstrate stable ferroelectricity in ultra‐thin ferroelectrics. However, the size effect in ferroelectric material is a problem that must be overcome for the miniaturization of ferroelectrics. This review discusses the reasons for and solutions to the size effect resulting from the complicated interactions of several factors within the ferroelectric.