Investigation of ferroelectric character in Wurtzite ferroelectrics using epitaxial films

• Project/Area Number: 18H01701
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Review Section: Basic Section 26020:Inorganic materials and properties-related
• Research Institution: Tokyo Institute of Technology
• Principal Investigator: FUNAKUBO Hiroshi 東京工業大学, 物質理工学院, 教授 (90219080)
• Co-Investigator(Kenkyū-buntansha): 清水 荘雄 国立研究開発法人物質・材料研究機構, 機能性材料研究拠点, 独立研究者 (60707587)
• Project Period (FY): 2018-04-01 – 2021-03-31
• Project Status: Completed (Fiscal Year 2020)
• Budget Amount: ¥17,420,000 (Direct Cost: ¥13,400,000、Indirect Cost: ¥4,020,000); Fiscal Year 2020: ¥4,550,000 (Direct Cost: ¥3,500,000、Indirect Cost: ¥1,050,000); Fiscal Year 2019: ¥4,550,000 (Direct Cost: ¥3,500,000、Indirect Cost: ¥1,050,000); Fiscal Year 2018: ¥8,320,000 (Direct Cost: ¥6,400,000、Indirect Cost: ¥1,920,000)
• Keywords: 酸化ハフニウム / 強誘電性 / 特性支配因子 / HfO2

Outline of Final Research Achievements

Stable ferroelectricity was observed for the films with 14-111 nm in thickness. Phase change temperature between tetragonal and orthorhombic phases shows large hysteresis. Field induced strain from tetragonal to orthorhombic phase was discovered. Sputtered film without heating shows good ferroelectric properties compatible to that of heat-treated one at 1000℃.

Academic Significance and Societal Importance of the Research Achievements

強誘電体の研究は、長年ぺロブスカイト構造とその関連構造の酸化物について主に行われてきたが、2011年に蛍石構造を有するHfO2基酸化物薄膜において強誘電性が見出された。しかし現有の強誘電体理論では説明できない点も多く、新たな理論の構築が待たれる状況にある。最大の課題は、蛍石強誘電体の強誘電特性の起源が解明されていないことにある。本研究は、研究代表者が世界で初めて作製に成功したエピタキシャル膜を用いて、蛍石構造強誘電体の特性支配因子を明らかにすることである。結晶構造やドメイン構造を制御する特性支配因子を解明することによって、従来の理論では説明できなかった蛍石構造強誘電体の強誘電性の起源に迫った。

Research Products

• [Int'l Joint Research] 国立宇宙物理・光学・電子研究所(メキシコ)
• [Journal Article] Preparation of 1 mm-thick Y-doped HfO2 ferroelectric films on (111)Pt/TiOx/SiO2/(001)Si substrates by the sputtering method and their ferroelectric and piezoelectric properties (2021)
  • Author(s): Reijiro Shimura, Takanori Mimura, Akinori Tateyama, Takao Shimizu, Tomoaki Yamada and Hiroshi Funakubo
  • Journal Title: Jpn. J. Appl. Phys Volume: 60 Issue: 3 Pages: 031009-031009
  • DOI: 10.35848/1347-4065/abe72e
  • Peer Reviewed / Open Access
• [Journal Article] Large thermal hysteresis of ferroelectric transition in HfO2-based ferroelectric films (2021)
  • Author(s): Takanori Mimura, Takao Shimizu, Osami Sakata, and Hiroshi Funakubo
  • Journal Title: Appl. Phys. Let. Volume: 118 Issue: 11 Pages: 112903-112903
  • DOI: 10.1063/5.0040934
  • Peer Reviewed
• [Journal Article] Electric‐Field‐Induced Ferroelectricity in 5%Y‐doped Hf0.5Zr0.5O2 : Transformation from the Paraelectric Tetragonal Phase to the Ferroelectric Orthorhombic Phase (2021)
  • Author(s): Shimizu Takao、Tashiro Yuki、Mimura Takanori、Kiguchi Takanori、Shiraishi Takahisa、Konnno Toyohiko J.、Sakata Osami、Funakubo Hiroshi
  • Journal Title: physica status solidi (RRL) - Rapid Research Letters Volume: on-line Issue: 5 Pages: 2000589-2000589
  • DOI: 10.1002/pssr.202000589
  • Peer Reviewed
• [Journal Article] Preparation of near-1-µm-thick {100}-oriented epitaxial Y-doped HfO₂ ferroelectric films on (100)Si substrates by a radio-frequency magnetron sputtering method (2020)
  • Author(s): Reijiro Shimura, Takanori Mimura, Takao Shimizu, Yoshitomo Tanaka, Yukari Inoue, and Hiroshi Funakubo
  • Journal Title: Journal of the Ceramic Society of Japan Volume: 128 Issue: 8 Pages: 539-543
  • DOI: 10.2109/jcersj2.20019
  • NAID: 130007883941
  • ISSN: 1348-6535, 1882-0743
  • Year and Date: 2020-08-01
  • Peer Reviewed / Open Access
• [Journal Article] Room-temperature deposition of ferroelectric HfO2-based films by the sputtering method (2020)
  • Author(s): Takanor Mimura, Takao Shimizu, Hiroshi Uchida, Hiroshi Funakubo
  • Journal Title: Applied Physics Letters Volume: 116 Issue: 6 Pages: 062901-062901
  • DOI: 10.1063/1.5140612
  • Peer Reviewed
• [Journal Article] Thickness- and orientation- dependences of Curie temperature in ferroelectric epitaxial Y doped HfO2 films (2020)
  • Author(s): Takanori Mimura, Takao Shimizu, Yoshio Katsuya, Osami Sakata, Hiroshi Funakubo
  • Journal Title: Japanese Journal of Applied Physics Volume: 59 Issue: SG Pages: SGGB04-SGGB04
  • DOI: 10.35848/1347-4065/ab6d84
  • Peer Reviewed
• [Journal Article] NiSi2 as a bottom electrode for enhanced endurance of ferroelectric Y-doped HfO2 thin films (2020)
  • Author(s): Joel Molina-Reyes, Takuya Hoshii, Shun-Ichiro Ohmi, Hiroshi Funakubo, Atsushi Hori, Ichiro Fujiwara, Hitoshi Wakabayashi, Kazuo Tsutsui, Kuniyuki Kakushima
  • Journal Title: Japanese Journal of Applied Physics Volume: 59 Issue: SG Pages: SGGB06-SGGB06
  • DOI: 10.35848/1347-4065/ab6b7c
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Preparation of near-1-mm-thick {100}-oriented epitaxial Y-doped HfO2 ferroelectric films on (100)Si substrates by an RF magnetron sputtering method (2020)
  • Author(s): Reijiro Shimura, Takanori Mimura, Takao Shimizu, Yoshitomo Tanaka, Yukari Inoue, Hiroshi Funakubo
  • Journal Title: Journal of the Ceramic Society of Japan Volume: -
  • Peer Reviewed
• [Journal Article] Formation of the orthorhombic phase in CeO2-HfO2 solid solution epitaxial thin films and their ferroelectric properties (2019)
  • Author(s): Shiraishi T.、Choi S.、Kiguchi T.、Shimizu T.、Funakubo H.、Konno T. J.
  • Journal Title: Applied Physics Letters Volume: 114 Issue: 23 Pages: 232902-232902
  • DOI: 10.1063/1.5097980
  • Peer Reviewed
• [Journal Article] Ferroelectricity in YO1.5-HfO2 films around 1μm in thickness (2019)
  • Author(s): Takanori Mimura, Takao Shimizu, Hiroshi Funakubo
  • Journal Title: Applied Physics Letters Volume: 115 Issue: 3 Pages: 032901-032901
  • DOI: 10.1063/1.5097880
  • Peer Reviewed
• [Journal Article] Effects of heat treatment and in-situ high temperature XRD study on the formation of ferroelectric epitaxial Y doped HfO2 film (2019)
  • Author(s): Takanori Mimura, Takao Shimizu, Takanori Kiguchi, Akihiro Akama, Toyohiko J. Konno, Yoshio Katsuya, Osami Sakata, and Hiroshi Funakubo
  • Journal Title: Jpn. J. Appl. Phys. Volume: 58 Issue: SB Pages: SBBB09-SBBB09
  • DOI: 10.7567/1347-4065/aafed1
  • Peer Reviewed
• [Journal Article] Fabrication of ferroelectric Fe doped HfO2 epitaxial thin films by ion-beam sputtering method and their characterization (2018)
  • Author(s): Takahisa Shiraishi, Sujin Choi, Takanori Kiguchi, Takao Shimizu, Hiroshi Uchida4, Hiroshi Funakubo, and Toyohiko J. Konno
  • Journal Title: Japanese Journal of Applied Physics Volume: 57 Issue: 11S Pages: 11UF02-11UF02
  • DOI: 10.7567/jjap.57.11uf02
  • NAID: 210000149811
  • Peer Reviewed
• [Journal Article] Thickness-dependent crystal structure and electric properties of epitaxial ferroelectric Y2O3-HfO2 films (2018)
  • Author(s): Takanori Mimura, Takao Shimizu, Hiroshi Uchida, Osami Sakata, and Hiroshi Funakubo
  • Journal Title: Appl. Phys. Lett. Volume: 113 Issue: 10 Pages: 102901-102901
  • DOI: 10.1063/1.5040018
  • Peer Reviewed
• [Journal Article] Crystallization behavior and ferroelectric property of HfO2-ZrO2 films fabricated by chemical solution deposition (2018)
  • Author(s): Shuhei Nakayama, Hiroshi Funakubo, and Hiroshi Uchida
  • Journal Title: Jpn. J. Appl. Phys. Volume: 57 Issue: 11S Pages: 11UF06-11UF06
  • DOI: 10.7567/jjap.57.11uf06
  • NAID: 210000149815
  • Peer Reviewed
• [Journal Article] Epitaxial ferroelectric Y-doped HfO2 film grown by the RF magnetron sputtering (2018)
  • Author(s): Taisei Suzuki, Takao Shimizu, Takanori Mimura, Hiroshi Uchida, and Hiroshi Funakubo
  • Journal Title: Jpn. J. Appl. Phys. Volume: 57 Issue: 11S Pages: 11UF15-11UF15
  • DOI: 10.7567/jjap.57.11uf15
  • NAID: 210000149824
  • Peer Reviewed
• [Journal Article] Ferroelectricity mediated by ferroelastic domain switching in HfO2-based epitaxial thin films (2018)
  • Author(s): Takao Shimizu, Takanori Mimura, Takanori Kiguchi, Takahisa Shiraishi, Toyohiko Konno, Yoshio Katsuya, Osami Sakata, and Hiroshi Funakubo
  • Journal Title: Appl. Phys. Lett. Volume: 113 Issue: 21 Pages: 212901-212901
  • DOI: 10.1063/1.5055258
  • Peer Reviewed
• [Presentation] スパッタリング法によるY-HZO強誘電体厚膜の室温製膜とその電気特性および圧電特性評価 (2021)
  • Author(s): 志村礼司郎、三村和仙、舘山明紀、清水荘雄、白石貴久、舟窪浩
  • Organizer: 第68回応用物理学会春季学術講演会
• [Presentation] スパッタリング法によるHfO2基強誘電体厚膜のシリコン基板上への室温製膜とその電気特性および圧電特性評価 (2020)
  • Author(s): 志村礼司郎、三村和仙、舘山明紀、清水荘雄、舟窪浩
  • Organizer: 第81回応用物理学会秋季学術講演会
• [Presentation] HfO2基材料における強誘電相生成機構 (2020)
  • Author(s): 清水荘雄、田代裕貴、三村和仙、舟窪浩
  • Organizer: 第40回電子材料研究討論会プログラム
• [Presentation] HfO2基薄膜のZr, Yドープによる結晶相変化と強誘電相の安定性 (2020)
  • Author(s): 田代裕貴、三村和仙、清水荘雄、勝矢良雄、坂田修身、木口賢紀、白石貴久、今野豊彦、舟窪浩
  • Organizer: 第58回セラミックス基礎科学討論会
• [Presentation] エピタキシャルHfO2基膜を用いた直方晶相安定化の調査 (2020)
  • Author(s): 三村和仙、清水荘雄、舟窪浩
  • Organizer: 第67回応用物理学会春季学術講演会
• [Presentation] スパッタリング法によるHfO2基強誘電体厚膜の室温製膜とその電気特性評価 (2020)
  • Author(s): 志村礼司郎、三村和仙、舘山明紀、清水荘雄、舟窪浩
  • Organizer: 第67回応用物理学会春季学術講演会
• [Presentation] Robust ferroelectricity in thick HfO2-based film (2019)
  • Author(s): Takao Shimizu, Takanori Mimura, Hiroshi Funakubo
  • Organizer: STAC-11 (The 11th International Conference on the Science and Technology for Advanced Ceramics)
  • Int'l Joint Research
• [Presentation] Robust Ferroelectricity in Y-Doped HfO2 Films (2019)
  • Author(s): Takao Shimizu, Takanori Mimura, Hiroshi Funakubo
  • Organizer: F2cπ2 2019 (Joint ISAF-ICE-EMF-IWPM-PFM meeting 2019)
  • Int'l Joint Research
• [Presentation] Thickness-dependent crystal structure of epitaxial ferroelectric 0.07YO1.5-0.93HfO2 and HZO films (2019)
  • Author(s): Takanori Mimura, Takao Shimizu, Hiroshi Funakubo
  • Organizer: ISIF 2019 (7th International Symposium on Intagrated Functionalities)
  • Int'l Joint Research
• [Presentation] Endurance Improvement in Ferroelectric Y-doped HfO2 Thin Films on NiSi2 with Low-Thermal Budget Processing (2019)
  • Author(s): J. Molina Reyes, T. Hoshii, S.-I. Ohmi, H. Funakubo, A. Hori, I. Fujiwara, H. Wakabayashi, K. Tsutsui, K. Kakushima
  • Organizer: SSDM 2019 (2019 International Conference on Solid State Devices and Materials)
  • Int'l Joint Research
• [Presentation] Thickness- and orientation-dependence of Curie temperature of ferroelectric epitaxial HfO2 based films (2019)
  • Author(s): T. Mimura, T. Shimizu, Y. Katsuya, O. Sakata, H. Funakubo
  • Organizer: SSDM 2019 (2019 International Conference on Solid State Devices and Materials)
  • Int'l Joint Research
• [Presentation] スパッタリング法を用いたY:HfO2強誘電体膜の室温成膜 (2019)
  • Author(s): 三村和仙、清水荘雄、舟窪浩
  • Organizer: 第80回応用物理学会秋季学術講演会
• [Presentation] HfO2基薄膜の電界誘起相転移 (2019)
  • Author(s): 田代裕貴、三村和仙、清水荘雄、勝矢良雄、坂田修身、木口賢紀、白石貴久、今野豊彦、舟窪浩
  • Organizer: 第80回応用物理学会秋季学術講演会
• [Presentation] Preparation and characterization of Y, Zr-doped HfO2 thin films by PLD method (2019)
  • Author(s): Yu-ki Tashiro, Takanori Mimura, Takao Shimizu, Hiroshi Funakubo
  • Organizer: CJFMA11 (The 11th China and Japan Symposium on Ferroelectric Materials and Their Applications)
  • Int'l Joint Research
• [Presentation] The phase stability and epitaxial growth of HfO2-based ferroelectric materials (2019)
  • Author(s): Takao Shimizu, Takanori Mimura, Hiroshi Funakubo
  • Organizer: PACRIM13 (The 13th Pacific Rim Conference of Ceramic Societies)
  • Int'l Joint Research
• [Presentation] Preparation and Characterization of Y, Zr-doped HfO2 Thin Film by PLD Method (2019)
  • Author(s): Yu-ki Tashiro, Takanori Mimura, Takao Shimizu, Hiroshi Funakubo
  • Organizer: 19th US-Japan Seminar on Dielectric and Piezoelectric Ceramics
  • Int'l Joint Research
• [Presentation] Recent Progress on Ferroelectric HfO2 Epitaxial Films (2019)
  • Author(s): Takao Shimizu, Takanori Mimura, Hiroshi Funakubo
  • Organizer: 19th US-Japan Seminar on Dielectric and Piezoelectric Ceramics
  • Int'l Joint Research
• [Presentation] Stability of Ferroelectric Orthorhombic Phase in Epitaxial HfO2-based Films (2019)
  • Author(s): Takanori Mimura, Takao Shimizu, Yoshio Katsuya, Osami Sakata, Hiroshi Funakubo
  • Organizer: 19th US-Japan Seminar on Dielectric and Piezoelectric Ceramics
  • Int'l Joint Research
• [Presentation] スパッタリング法を用いたY:HfO2強誘電体厚膜の作製とその電気特性評価 (2019)
  • Author(s): 志村礼司郎、三村和仙、清水荘雄、舟窪浩
  • Organizer: 第39回電子材料研究討論会
• [Presentation] Phase stability and property control of ferroelectric HfO2 films (2019)
  • Author(s): Hiroshi Funakubo, Takanori Mimura, Takao Shimizu
  • Organizer: MRM2019 (Materials Research Meeting 2019
  • Int'l Joint Research / Invited
• [Presentation] PLD法を用いたY, ZrドープHfO2薄膜の作製と評価 (2019)
  • Author(s): 田代裕貴、三村和仙、清水荘雄、舟窪浩
  • Organizer: 第57回セラミックス基礎科学討論会
• [Presentation] PLD法を用いたY, ZrドープHfO2薄膜の作製と評価 (2019)
  • Author(s): 田代裕貴、三村和仙、清水荘雄、舟窪浩
  • Organizer: 第66回応用物理学会春季学術講演会
• [Presentation] Phase Stability of HfO2-based Ferroelectric Materials and Their Property Control (2018)
  • Author(s): Hiroshi Funakubo, Takao Shimizu, Takanori Mimura
  • Organizer: 2018 KPS Fall Meeting
  • Int'l Joint Research / Invited
• [Presentation] HfO2基強誘電体の相安定性と特性制御 (2018)
  • Author(s): 舟窪浩、清水荘雄、三村和仙
  • Organizer: 第79回応用物理学会秋季学術講演会
  • Invited
• [Presentation] Effects of heat treatment and in situ high temperature XRD study on the formation of ferroelectric epitaxial HfO2 based film (2018)
  • Author(s): Takanori Mimura, Takao Shimizu, Takanori Kiguchi, Akihiro Akama, Toyohiko J. Konno, Yoshio Katsuya, Osami Sakata, and Hiroshi Funakubo
  • Organizer: SSDM 2018 (2018 International Conference on Solid State Devices and Materials)
  • Int'l Joint Research
• [Presentation] Growth of epitaxial Y2O3-doped ferroelectric HfO2 films by sputtering method and their characterization (2018)
  • Author(s): Taisei Suzkuki, Takanori Mimura, Takao Shimizu, Hiroshi Uchida, and Hiroshi Funakubo
  • Organizer: SSDM 2018 (2018 International Conference on Solid State Devices and Materials)
  • Int'l Joint Research
• [Presentation] HfO2基強誘電体厚膜の作製と電気特性制御 (2018)
  • Author(s): 清水荘雄、三村和仙、舟窪浩
  • Organizer: 2018年度セラミックス総合研究会
• [Remarks] 東京工業大学 物質理工学院 材料系材料コース 舟窪研究室
  • URL: https://f-lab.iem.titech.ac.jp/
• [Remarks] 東京工業大学 物質理工学院 材料系材料コース 舟窪研究室
  • URL: http://f-lab.iem.titech.ac.jp/f-lab.htm
• [Remarks] 東京工業大学 物質理工学院 材料系 材料コース 舟窪研究室
  • URL: http://f-lab.iem.titech.ac.jp/f-lab.htm
• [Patent(Industrial Property Rights)] 強誘電性薄膜の製造方法、強誘電性薄膜、及びその用途 (2019)
  • Inventor(s): 舟窪浩、清水荘雄、三村和仙、中村美子
  • Industrial Property Rights Holder: 舟窪浩、清水荘雄、三村和仙、中村美子
  • Industrial Property Rights Type: 特許
  • Industrial Property Number: 2019-086836
  • Filing Date: 2019
• [Patent(Industrial Property Rights)] 圧電体の製造方法、圧電体、及び圧電体素子又は装置 (2019)
  • Inventor(s): 舟窪浩、清水荘雄、三村和仙、中村美子
  • Industrial Property Rights Holder: 舟窪浩、清水荘雄、三村和仙、中村美子
  • Industrial Property Rights Type: 特許
  • Industrial Property Number: 2019-086840
  • Filing Date: 2019