Park Min Hyuk, Hwang Cheol Seong
School of Materials Science and Engineering, College of Engineering, Pusan National University, Busandaehak-ro 63beon-gil 2, Geumjeong-gu, Busan, 46241, Republic of Korea.
Rep Prog Phys. 2019 Dec;82(12):124502. doi: 10.1088/1361-6633/ab49d6. Epub 2019 Oct 1.
Ferroelectricity in fluorite-structure oxides like hafnia and zirconia have attracted increasing interest since 2011. Two spontaneous polarizations of the fluorite-structure ferroelectrics are considered highly promising for nonvolatile memory applications, with their superior scalability and Si compatibility compared to the conventional perovskite-structure ferroelectrics. Besides, antiferroelectricity originating from a field-induced phase transition between the paraelectric and ferroelectric phases in fluorite-structure oxides is another highly interesting matter. It was suggested that the field-induced phase transition could be utilized for energy conversions between thermal and electrical energy, as well as for energy storage. The important energy-related applications of antiferroelectric fluorite-structure oxides, however, have not been systematically reviewed to date. Thus, in this work, the fluorite-structure antiferroelectrics are reviewed from their fundamentals to their applications based on pyroelectricity as well as antiferroelectricity. Another important application field of the fluorite-structure antiferroelectrics is the semiconductor memory devices. The fluorite-structure antiferroelectrics can be utilized for antiferroelectric random-access-memories, negative capacitance field-effect-transistors, and flash memories. Moreover, the recently reported morphotropic phase boundary (MPB) between the ferroelectric and antiferroelectric phases in this material system marks another significant progress in this material system, and thus, the fundamentals and applications of the MPB phase are also reviewed.
自2011年以来，氧化铪和氧化锆等萤石结构氧化物中的铁电性引起了越来越多的关注。萤石结构铁电体的两种自发极化因其与传统钙钛矿结构铁电体相比具有卓越的可扩展性和与硅的兼容性，在非易失性存储器应用中被认为极具潜力。此外，萤石结构氧化物中由场诱导的顺电相和铁电相之间的相变产生的反铁电性是另一个非常有趣的问题。有人提出，场诱导相变可用于热能与电能之间的能量转换以及能量存储。然而，迄今为止，反铁电萤石结构氧化物在重要的能量相关应用方面尚未得到系统的综述。因此，在这项工作中，基于热释电以及反铁电性，从萤石结构反铁电体的基本原理到其应用进行了综述。萤石结构反铁电体的另一个重要应用领域是半导体存储器件。萤石结构反铁电体可用于反铁电随机存取存储器、负电容场效应晶体管和闪存。此外，该材料体系中最近报道的铁电相和反铁电相之间的准同型相界（MPB）标志着该材料体系的又一重大进展，因此，也对准同型相界相的基本原理和应用进行了综述。
