Emerging Fluorite-Structured Antiferroelectrics and Their Semiconductor Applications

The ferroelectric properties of fluorite-structured oxides have attracted significant attention from researchers because of their potential applications in nonvolatile memory devices, which are enabled by their compatibility with the complementary metal oxide semiconductor technology and physical scalability to a thickness below 10 nm. Another important emerging property of these materials is their antiferroelectricity, which originates from the field-induced transition between the polar and nonpolar phases. Various applications of fluorite-structured antiferroelectrics, such as those in volatile logic devices and cell capacitors for dynamic random-access memory, engineered nonvolatile memory, and energy storage/conversion devices, have been recently proposed, although they have not been investigated in detail compared to fluorite-structured ferroelectrics. The volatile nature of fluorite-structured antiferroelectrics with a characteristic field-induced phase transition, which clearly distinguishes them from ferroelectrics, have endowed these materials with unique properties that cannot be achieved by ferroelectrics. Therefore, the emerging antiferroelectricity of fluorite-structured oxides is comprehensively reviewed in this paper from its fundamentals to various semiconductor applications based on the existing literature.