Ye, Kun Hee Jeong, Taeyoung Yoon, Seungjae Kim, Dohyun Kim, Yunjae Hwang, Cheol Seong Choi, Jung-Hae 2025-05-11T06:01:16Z 2025-05-11T06:01:16Z 2025-05-07 2026-03 1616-301X https://pubs.kist.re.kr/handle/201004/152417 This study proposes a new ferroelectric switching mechanism in HfO2-based ferroelectric films by using density functional theory calculations. It predicts a theoretical coercive field (E-c) consistent with the experimental value (approximate to 1 MV cm(-1)). To this end, this work considers the anisotropic nucleation and growth of reversed polarization along the three principal axes of the orthorhombic phase of HfO2 and ZrO2. This approach differs from the earlier theoretical study that assumed homogeneous switching and predicted too high E-c (approximate to 10 MV cm(-1)), and from the recent theoretical prediction that assumed domain switching but still predicted unrealistically high E-c. Along the b-direction involving the non-polar spacer sub-unit cell layer, the switching barriers (E(s)s) for nucleation and growth of a reversed domain are similar. In contrast, along the a-direction, which lacks a non-polar layer and is previously overlooked, nucleation affects neighboring polar layers, significantly reducing the E-s for growth. Switching types along the c-direction (homogeneous or stepwise) has little effect on the overall E-s. These distinct E-s characteristics along three directions predict an E-c of 1-2 MV cm(-1) for a 10-nm-thick (Hf,Zr)O-2 film, consistent with experimental results. English John Wiley & Sons Ltd. Ab Initio Study on 3D Anisotropic Ferroelectric Switching Mechanism and Coercive Field in HfO2 and ZrO2 Article 10.1002/adfm.202500390 1 Advanced Functional Materials, v.36, no.20 Advanced Functional Materials 36 20 N scie scopus Chemistry, Multidisciplinary Chemistry, Physical Nanoscience & Nanotechnology Materials Science, Multidisciplinary Physics, Applied Physics, Condensed Matter Chemistry Science & Technology - Other Topics Materials Science Physics Article; Early Access FILMS PIEZOELECTRICITY TRANSITION GROWTH ferroelectricity Hf1-xZrxO2 (HZO) 3D anisotropic switching mechanism ab initio calculations coercive field (E-c)