Domain switching mechanism in binary ferroelectric

2022 Fiscal Year Final Research Report

• Project/Area Number: 20H00314
• Research Category: Grant-in-Aid for Scientific Research (A)
• Allocation Type: Single-year Grants
• Section: 一般
• Review Section: Medium-sized Section 26:Materials engineering and related fields
• Research Institution: National Institute of Advanced Industrial Science and Technology
• Principal Investigator: Itoh Mitsuru 国立研究開発法人産業技術総合研究所, エレクトロニクス・製造領域, 招聘研究員 (30151541)
• Co-Investigator(Kenkyū-buntansha): 高島 浩 国立研究開発法人産業技術総合研究所, エレクトロニクス・製造領域, 上級主任研究員 (10357353) ; 森分 博紀 一般財団法人ファインセラミックスセンター, その他部局等, 主席研究員 (40450853) ; 佐藤 幸生 九州大学, 工学研究院, 准教授 (80581991)
• Project Period (FY): 2020-04-01 – 2023-03-31
• Keywords: 強誘電性 / ウルツァイト型 / 分極反転 / ２元化合物強誘電体

Outline of Final Research Achievements

In this study, we have attempted to synthesize nitride thin films by material synthesis based on our previous experience in ferroelectric design. The ferroelectricity of single-crystal thin films of wurtzite-type and κ-alumina-type compounds, which have been developed so far, was clarified experimentally and computationally, and the mechanism of polarization inversion in two uniaxial ferroelectric groups, which enables polarization inversion under an external electric field, was discussed in detail in connection with the effect of elemental substitution, and the optimum material selection and Experiments were conducted. We have explored the details of crystallinity, surface flatness, and cross-sectional structure of AlN and GaN matrices and Sc-doped materials by vapor-phase growth to realize high-quality thin films with excellent atomic flatness.

Free Research Field

無機固体化学

Academic Significance and Societal Importance of the Research Achievements

陽性、陰性の２元素からなる化合物強誘電体（ウルツァイト型）の分極反転メカニズムについて、実験と計算を通して普遍的な物質体系を構築し、２元化合物強誘電体の潜在能力を詳らかにすることにより、新規強誘電体の設計指針を世界に提案し展開する。得られた結果と既知の強誘電体の分極反転メカニズムを比較し、3元以上の強誘電体で第3の元素が化学結合で果たす役割を明確することで未知の強誘電体構造を設計・探索する際の戦略を得る。