Structural controlling in nano-scale and high-functionalization for multi-component ferroelectric oxide films by chemical vapor deposition

化学气相沉积多组分铁电氧化物薄膜的纳米级和高功能化结构控制

• 批准号: 05403017
• 负责人: HIRAI Toshio
• 金额: $ 8.83万
• 依托单位: Tohoku University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (A)
• 财政年份: 1993
• 资助国家: 日本
• 起止时间: 1993 至 1994
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-05403017/
• 关键词: multi-component ferroelectric oxide; thin film; bismuth titanate; Bi_4Ti_3O_<12>; chemical vapor deposition; epitaxial growth; ferroelectricity

There are lots of ferroelectric, piezoelectric, pyroelectric and optical materials in multi-component oxides, for example BaTiO_3, PbTiO_3, Bi_4Ti_3O_<12>, and LiNbO_3. It is necessary to prepare films of these materials and to achieve high-functionalization. We treid to prepare films of ferroelectric bismuth titanate (Bi_4Ti_3O_<12>) which belongs to multi-component oxide by chemical vapor deposition (CVD) and clarify the relationship of CVD condition of nano-scale structural controlling and ferroelectricity of the film.We have successfully controlled the composition of BIT films by using tri-ortho-tolyl-bismuth [Bi (o-Tol)_3] and di-isopropoxy-bis- (dipivaloyl metanato) -titanium [Ti (i-C_3H_7O)_2 (DPM)_2] as Bi and Ti sources. The films were stoichiometric and single phase. The film with excess Ti contains Bi_2Ti_2O_7 phase and the film with excess Bi contains Bi_<12>TiO_<20> as second phases. Crystal orientation and crystallite size were controlled in nano-scale. We found that the mechanisms of epitaxial and preferred growth depend on kinds of substrates and substrate temperatures. Grains size of the BIT films observed by electron microscope were nano-meter size. Uniformity of crystal orientation of these nano-scale grains improved with increasing substrate temperature.The value of the residual polarization increased and the coercive field decreased with increasing film thickness. When the thickness of the film were above 5mum, these value of BIT film were almost the same as the values of single crystals.

多组分氧化物中有很多铁电，压电，pyroelectric和光学材料，例如batio_3，pbtio_3，bi_4ti_3o_3o_ <12>和linbo_3。有必要准备这些材料的薄膜并实现高官能化。我们将titanate的铁电抗性二酯（BI_4TI_3O_ <12>）制备，该薄膜属于化学蒸气沉积（CVD）的多组分氧化物，并阐明纳米尺度结构控制和膜的CVD条件的关系。我们通过使用Tri-ortho-tolyl-Bismuth [BI（O-TOL）_3]和Di-di-Ispopoxy-bis-（dipivaloyl metanato）-titanium [ti（i-c_3h_7o）_2（dpm）_2（dpm）_2（dpm）_2 ]作为BI和TI来源。这些薄膜是化学计量和单相。过量Ti的膜包含BI_2TI_2O_7相，并且具有多余BI的膜包含BI_ <12> TIO_ <20>作为第二阶段。晶体方向和结晶石尺寸在纳米尺度中受到控制。我们发现，外延和首选生长的机制取决于底物和底物温度的种类。通过电子显微镜观察到的位膜的晶粒大小为纳米米大小。这些纳米级晶粒的晶体取向的均匀性随着底物温度的升高而改善。残留极化的值增加，强制场随着膜厚度的增加而降低。当膜的厚度高于5MUM时，这些位膜的值几乎与单晶的值相同。

项目成果

H.Yamane, M.Omori, A.Okubo and T.Hirai: "High-temperature phase transition of Y_4Al_2O_9" J.Amer.Ceram.Soc.76. 2382-2384 (1993)

H.Yamane、M.Omori、A.Okubo 和 T.Hirai：“Y_4Al_2O_9 的高温相变”J.Amer.Ceram.Soc.76。

後藤孝、陳俊雄、平井敏雄: "欠陥ペロブスカイトLaTa_3O_9の交流電気伝導と輸率測定" 日本セラミックス協会学術論文誌. 103. 50-53 (1995)

Takashi Goto、Toshio Chen、Toshio Hirai：“缺陷钙钛矿 LaTa_3O_9 的交流电传导和传输数测量”日本陶瓷学会杂志 103. 50-53 (1995)。

H.Masumoto,T.Goto,Y.Masuda,A.Baba and T.Hirai: "Epitaxial growth of Bi_4Ti_3O_<12> films by electron cyclotron resonance plasma sputtering" Proc.of the Thirty-sixth Japan Congress on Material Research,Ed.by R.Ota,S.Kikuti,T.Kitamura,K.Minosihima,S.Nomura,

H.Masumoto、T.Goto、Y.Masuda、A.Baba 和 T.Hirai：“通过电子回旋共振等离子体溅射技术外延生长 Bi_4Ti_3O_<12> 薄膜”，第三十六届日本材料研究大会论文集，Ed

T.Goto, C.W.Chen and T.Hirai: "A.C.electrical conduction and transport number measurements for defect-perovskite LaTa_3O_9" J.Ceram.Soc.Jpn.103. 50-53 (1995)

T.Goto、C.W.Chen 和 T.Hirai：“缺陷钙钛矿 LaTa_3O_9 的交流电传导和输运数测量”J.Ceram.Soc.Jpn.103。

H.Masumoto,M.Namerikawa and T.Hirai: "Preparation of bismuth titanate films by chemical vapor deposition" Proc.of first conference on processing materials for properties,Ed.by H.Henein and T.Oki,The Minerals,Metals and Materials Society. 1113-1116 (1993)

H.Masumoto、M.Namerikawa 和 T.Hirai：“通过化学气相沉积制备钛酸铋薄膜”Proc.of 第一次加工材料性能会议，H.Henein 和 T.Oki 编着，矿物、金属和