2002 Fiscal Year Annual Research Report

新強誘電体薄膜の探索

Research Project

Project/Area Number	12134206
Research Institution	Osaka Prefecture University
Principal Investigator	藤村紀文大阪府立大学, 大学院・工学研究科, 助教授 (50199361)
Co-Investigator(Kenkyū-buntansha)	田畑仁大阪大学, 産業科学研究所, 教授 (00263319) 松井利之大阪府立大学, 大学院・工学研究科, 助手 (20219372)
Keywords	新強誘電体メモリ / YMnO_3 / 強誘電体ゲートトランジスタ / 新強誘電体物質設計 / 減分極電界 / カルコゲン系強誘電体 / BaZrO_3 / リラクサー強誘電体
Research Abstract	強誘電体ゲートトランジスタに最適な新強誘電体物質の探索に関しては、藤村がYMnO_3系物質を、田畑がカルコゲン系物質を中心に検討を行っている。YMnO_3系物質についてはサイト置換によるキュリー点の低減、強誘電特性の改善を目的に、カルコゲン系物質に関しては、自発分極と抗電界の増大、界面特性の向上を目的とした研究に着手した。前者はMFIS、後者はMFSに向けた物質として別個に開発されているが、特性の評価は大学間を連携して行っている。当該デバイスの問題点を記憶保持特性の改善と認識し、記憶保持特性に及ぼす分極状態の影響,界面分極や空間電荷の再配列、リーク電流、減分極電界の影響に関しては(藤村)ほぼ解明された。本年度の重要な研究結果としてはリーク電流との相関が明らかになったことである.また,実際のデバイス特性を測定するためにトランジスタの作成にも着手した.当初予定していた結果を大幅に上回っている. これらのメモリー保持特性には、金属/強誘電体/(絶縁体)/半導体のバンドアライメントの影響を強く受けるために、XPSやSPMを用いた仕事関数、価電子帯準位や伝導帯準位の測定方法を確立した(田畑)。低エネルギープラズマ窒化装置を自作し、超平坦極薄酸窒膜の形成に成功し、この領域での研究の飛躍が期待させる。その他、藤村はBaZrO_3のSi上へのエピタキシャル成長に成功するとともにZnO : Li強誘電体を用いて高速光スイッチング動作に成功するなどの成果が得られた。田畑は高誘電率新物質としてBa(Zr,Ti)O_3系の超格子の作成を試みている。現在は安田(岐阜大)班のバルクの情報を基に単層膜での基礎検討を行い、リラクサー的挙動を確認している。

Research Products
(20 results)

All Other

All Publications (20 results)

[Publications] D.Ito, N.Fujimura*, T.Yoshimura, T.Ito: "Ferroelectric properties of YMnO_3 epitaxial films for ferroelectric-gate field effect transistors"Journal of Applied Physics. (accepted for publication). (2003)
[Publications] T.Yokota, N.Fujimura, T.Wada, S.Hamasaki, T.Ito: "The Effect of Carrier for Magnetic and Magneto-transport Properties of Si : Ce Films"Journal of Applied Physics. (accepted for publication). (2003)
[Publications] T.Edahiro, N.Fujimura, T.Ito: "Formation of Two-Dimensional Electron Gas and the Magneto-Transport Behavior of ZnMnO/ZnO Heterostructure"Journal of Applied Physics. (accepted for publication). (2003)
[Publications] T.Yokota, N.Fujimura, T.Ito: "Magnetic and Magneto-transport Properties of Solid Phase Epitaxiallv Grown Si : Ce Films"Journal of Applied Physics. (accepted for publication). (2003)
[Publications] N.Fujimura, D.Ito, H.Sakata, T.Ito: "Ferromagnetic and Ferroelectric Behaviors of A Site Substituted YMnO_3 Based Epitaxia1 Thin Films"Journal of Applied Physics. (accepted for publication). (2003)
[Publications] Ito D, Fujimura N, Ito T: "The effect of leakage current on the retention property of YMnO_3 based MFIS capacitor"Integrated Ferroelectrics. 49. 41-49 (2002)
[Publications] T.Matsui, H.Tanaka, N.Fujimura, T.Ito, H.Mabuchi, K.Morii: "Structural, Dielectric and Magnetic Properties of Epitaxially Grown BaFeO_3 Thin Films on (100) SrTiO3 Single-crystal Substrates"Applied Physics Letters. Vol.81. 2764-2766 (2002)
[Publications] T.Nagata, A.Ashida, Y.Takagi, N.Fujimura, T.Ito: "Electro-optic Effect in Epitaxial ZnO : Mn Thin Films"Japanese Journal of Applied Physics. 41. 6916-6918 (2002)
[Publications] T.Matsui, Y.Kitano, N.Fujimura, K.Morii, T.Ito: "Crystal Growth and Interface Characterization of Dielectric BaZrO_3 Thin Films on Si Substrates"Japanese Journal of Applied Physics. 41. 6639-6642 (2002)
[Publications] Y.Kitano, T.Matsui, N.Fujimura, K.Morii, T.Ito: "Thin Film Crystal Growth of BaZrO_3 at Low Oxygen Partial Pressure"Journal of Crystal Growth. 243(1). 164-169 (2002)
[Publications] K.Kakuno, D.Ito, N.Fujimura, T.Matsui, T.Ito: "Growth Process and Interfacial Structure of Epitaxial Y_2O_3/Si Thin Films Deposited by Pulsed Laser Deposition"Journal of Crystal Growth. 237(Part1). 487-491 (2002)
[Publications] D.Ito, N.Fujimura, K.Kakuno, T.Ito: "Retention Property Analysis of Epitaxially Grown YMnO_3/Y_2O_3/Si Capacitor"Ferroelectrics. 271. 87-92 (2002)
[Publications] T.Yokota, N.Fujimura, T.Wada, S.Hamasaki, T.Ito: "Effect of Substitutionally Dissolved Ce in Si on the Magnetic and Electric Properties of Magnetic Semiconductor : Si_<1-x>Ce_x Films"Applied Phys. Letters. 81. 4023-4025 (2002)
[Publications] T.Matsui, H.Tanaka, N.Fujimura, T.Ito, H.Mabuchi, K.Morii: "Structural, Dielectric and Magnetic Properties of Epitaxially Grown BaFeO_3 Thin Films on (100) SrTiO3 Single-crystal Substrates"Applied Phys. Letters. Vol.81. 2764-2766 (2002)
[Publications] T.Yokota, N.Fujimura, T.Wada, S.Hamasaki, T.Ito: "Ce Concentration Dependence on the Magnetic and Transport Properties of Ce Doped Si Epitaxial Films Prepared by Molecular Beam Epitaxy"Journal of Applied Physics. 91 10. 7905-7907 (2002)
[Publications] T.Shimuta, O.Nakagawara, T.Makino, A.Arai, H.Tabata, T.Kawai: "Enhancement of Remanent Polarization in epitaxial BaTiO_3/SrTiO_3 Superlattices with "Asymmetric" Structure"Journal of Applied Physics. 91. 2290-2294 (2002)
[Publications] Y.Hotta, E.Rokuta, J.-H.Choi, H.Tabata, T.Kawai: "Determination of the Optical Cation Composition of Ferroelectric (ZnxCd1-x)S Thin Films for Applications to Silicon Based Nonvolatile Memories"Applied Physics Lett.. 80. 3180-3182 (2002)
[Publications] O.Nakagawara, T.Shimuta, T.Makino, A.Arai, H.Tabata, T.Kawai: "Dependence of Dielectric and Ferroelectric Behaviors on Growth Orientation in Epitaxial BaTiO_3/SrTiO_3 Superlattices"Vacuum. 66. 397-401 (2002)
[Publications] E.Rokuta, H.Tabata, T.Kawai: "Strong Dependencies of Electrical Characteristics of Bi_4Ti_3O_<12>/Oxynitride/Si Interfacial Proximity on Nitrogen Plasma"Journal of Vacuum Science & Technology B. (in press). (2003)
[Publications] Y.-G.Park, H.-Y.Lee, H.Tanaka, H.Tabata, T.Kawai: "Photo-induced Ferroelectric Hysteresis Curve in Organic CuPc Photoconductor/Inorganic BaTiO_3 Ferroelectric Hetero-junction Photomemory"Applied Physics Lett.. 81. 1318-1320 (2002)

2002 Fiscal Year Annual Research Report

新強誘電体薄膜の探索

Principal Investigator

藤村 紀文 大阪府立大学, 大学院・工学研究科, 助教授 (50199361)

Research Products

[Publications] D.Ito, N.Fujimura*, T.Yoshimura, T.Ito: "Ferroelectric properties of YMnO_3 epitaxial films for ferroelectric-gate field effect transistors"Journal of Applied Physics. (accepted for publication). (2003)

[Publications] T.Yokota, N.Fujimura, T.Wada, S.Hamasaki, T.Ito: "The Effect of Carrier for Magnetic and Magneto-transport Properties of Si : Ce Films"Journal of Applied Physics. (accepted for publication). (2003)

[Publications] T.Edahiro, N.Fujimura, T.Ito: "Formation of Two-Dimensional Electron Gas and the Magneto-Transport Behavior of ZnMnO/ZnO Heterostructure"Journal of Applied Physics. (accepted for publication). (2003)

[Publications] T.Yokota, N.Fujimura, T.Ito: "Magnetic and Magneto-transport Properties of Solid Phase Epitaxiallv Grown Si : Ce Films"Journal of Applied Physics. (accepted for publication). (2003)

[Publications] N.Fujimura, D.Ito, H.Sakata, T.Ito: "Ferromagnetic and Ferroelectric Behaviors of A Site Substituted YMnO_3 Based Epitaxia1 Thin Films"Journal of Applied Physics. (accepted for publication). (2003)

[Publications] Ito D, Fujimura N, Ito T: "The effect of leakage current on the retention property of YMnO_3 based MFIS capacitor"Integrated Ferroelectrics. 49. 41-49 (2002)

[Publications] T.Matsui, H.Tanaka, N.Fujimura, T.Ito, H.Mabuchi, K.Morii: "Structural, Dielectric and Magnetic Properties of Epitaxially Grown BaFeO_3 Thin Films on (100) SrTiO3 Single-crystal Substrates"Applied Physics Letters. Vol.81. 2764-2766 (2002)

[Publications] T.Nagata, A.Ashida, Y.Takagi, N.Fujimura, T.Ito: "Electro-optic Effect in Epitaxial ZnO : Mn Thin Films"Japanese Journal of Applied Physics. 41. 6916-6918 (2002)

[Publications] T.Matsui, Y.Kitano, N.Fujimura, K.Morii, T.Ito: "Crystal Growth and Interface Characterization of Dielectric BaZrO_3 Thin Films on Si Substrates"Japanese Journal of Applied Physics. 41. 6639-6642 (2002)

[Publications] Y.Kitano, T.Matsui, N.Fujimura, K.Morii, T.Ito: "Thin Film Crystal Growth of BaZrO_3 at Low Oxygen Partial Pressure"Journal of Crystal Growth. 243(1). 164-169 (2002)

[Publications] K.Kakuno, D.Ito, N.Fujimura, T.Matsui, T.Ito: "Growth Process and Interfacial Structure of Epitaxial Y_2O_3/Si Thin Films Deposited by Pulsed Laser Deposition"Journal of Crystal Growth. 237(Part1). 487-491 (2002)

[Publications] D.Ito, N.Fujimura, K.Kakuno, T.Ito: "Retention Property Analysis of Epitaxially Grown YMnO_3/Y_2O_3/Si Capacitor"Ferroelectrics. 271. 87-92 (2002)

[Publications] T.Yokota, N.Fujimura, T.Wada, S.Hamasaki, T.Ito: "Effect of Substitutionally Dissolved Ce in Si on the Magnetic and Electric Properties of Magnetic Semiconductor : Si_<1-x>Ce_x Films"Applied Phys. Letters. 81. 4023-4025 (2002)

[Publications] T.Matsui, H.Tanaka, N.Fujimura, T.Ito, H.Mabuchi, K.Morii: "Structural, Dielectric and Magnetic Properties of Epitaxially Grown BaFeO_3 Thin Films on (100) SrTiO3 Single-crystal Substrates"Applied Phys. Letters. Vol.81. 2764-2766 (2002)

[Publications] T.Yokota, N.Fujimura, T.Wada, S.Hamasaki, T.Ito: "Ce Concentration Dependence on the Magnetic and Transport Properties of Ce Doped Si Epitaxial Films Prepared by Molecular Beam Epitaxy"Journal of Applied Physics. 91 10. 7905-7907 (2002)

[Publications] T.Shimuta, O.Nakagawara, T.Makino, A.Arai, H.Tabata, T.Kawai: "Enhancement of Remanent Polarization in epitaxial BaTiO_3/SrTiO_3 Superlattices with "Asymmetric" Structure"Journal of Applied Physics. 91. 2290-2294 (2002)

[Publications] Y.Hotta, E.Rokuta, J.-H.Choi, H.Tabata, T.Kawai: "Determination of the Optical Cation Composition of Ferroelectric (ZnxCd1-x)S Thin Films for Applications to Silicon Based Nonvolatile Memories"Applied Physics Lett.. 80. 3180-3182 (2002)

[Publications] O.Nakagawara, T.Shimuta, T.Makino, A.Arai, H.Tabata, T.Kawai: "Dependence of Dielectric and Ferroelectric Behaviors on Growth Orientation in Epitaxial BaTiO_3/SrTiO_3 Superlattices"Vacuum. 66. 397-401 (2002)

[Publications] E.Rokuta, H.Tabata, T.Kawai: "Strong Dependencies of Electrical Characteristics of Bi_4Ti_3O_<12>/Oxynitride/Si Interfacial Proximity on Nitrogen Plasma"Journal of Vacuum Science & Technology B. (in press). (2003)

[Publications] Y.-G.Park, H.-Y.Lee, H.Tanaka, H.Tabata, T.Kawai: "Photo-induced Ferroelectric Hysteresis Curve in Organic CuPc Photoconductor/Inorganic BaTiO_3 Ferroelectric Hetero-junction Photomemory"Applied Physics Lett.. 81. 1318-1320 (2002)

藤村紀文大阪府立大学, 大学院・工学研究科, 助教授 (50199361)