Preparation and Characterization of Ferroelectric Thin Films for Memories by the Chemical Process

化学方法制备存储器用铁电薄膜并表征

• 批准号: 04555188
• 负责人: TOHGE Noboru
• 金额: $ 4.48万
• 依托单位: Kinki University (1993)Osaka Prefecture University (1992)
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Developmental Scientific Research (B)
• 财政年份: 1992
• 资助国家: 日本
• 起止时间: 1992 至 1993
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-04555188/
• 关键词: Sol-gel process; Ferroelectrics; PZT; PLZT; Bi_4Ti_3O_<12>; Thin film; Patterning; Chemical modification; ペロブスカイト構造; パターニング; ペロブスカイト相; 微細加工

Ferroelectric memories have recently been attracting much attention. The sol-gel process, a typical chemical process, is promising for the preparation of these ferroelectric films. The present study has been done to develop the preparation process and characterize the resultant films, with the following results.(1) PZT films were prepared from Zr- and Ti-butoxides modified with acetylacetone and trihydrated lead acetate. The solubility of the acetate in ethanol was found to increase in the presence of monoethanolamine. The heat-treatment of the gel films at 700 C produced ferroelectric films of the perovskite single phase.(2) Based on the results on PZT films, PLZT films were prepared using lanthanum nitrate in a part of lead acetate. Homogeneous thin films with uniform compositional distribution have been formed. Their properties such as ferroelectricity and leak current were studied as a function of film thickness.(3) Bi-ethoxide stabilized with monoethanolamine and Ti-butoxide modified with acetylacetone were used for the preparation of Bi_4Ti_3O_<12> ferroelectric films and their properties were studied is terms of preparation conditions.(4) The UV-irradiation of gel films modified with beta-diketones was found to decrease their solubility in acidic solutions or alcohol solutions. This finding was applicable to the fine-patterning of single component such as ZrO_2 and TiO_2 and moreover ferroelectric thin films of multicomponent.(5) Hydrolysis of a number of trifuctional alkoxysilanes was studied and the properties of sol-gel derived SiO_2 films were examined in an atmosphere of high temperature and humidity.

铁电存储器最近引起了广泛关注。溶胶-凝胶工艺是一种典型的化学工艺，在制备这些铁电薄膜方面具有广阔的前景。本研究对制备工艺进行了开发并对所得薄膜进行了表征，取得了以下成果：(1)以乙酰丙酮和三水醋酸铅改性的Zr-和Ti-丁氧化物为原料制备了PZT薄膜。发现乙酸盐在乙醇中的溶解度在单乙醇胺存在下增加。将凝胶薄膜在700℃下热处理，得到钙钛矿单相铁电薄膜。(2)基于PZT薄膜的研究结果，用硝酸镧和部分醋酸铅制备了PLZT薄膜。已形成具有均匀成分分布的均质薄膜。研究了它们的铁电性和漏电流等性能随膜厚的变化。(3)采用单乙醇胺稳定的Bi-乙醇盐和乙酰丙酮改性的Ti-丁醇盐制备了Bi_4Ti_3O_<12>铁电薄膜，并在制备条件下研究了其性能。(4)改性凝胶薄膜的紫外辐照。 发现与 β-二酮结合会降低其在酸性溶液或酒精溶液中的溶解度。这一发现适用于ZrO_2、TiO_2等单组分以及多组分铁电薄膜的精细图案化。(5)研究了多种三官能烷氧基硅烷的水解情况,并考察了溶胶-凝胶法制备的SiO_2薄膜在高温高湿气氛下的性能。

项目成果

K.Izumi: "Hydrolysis of Trifunctional Alkoxysilanes and Corrosion Resistance of Steel Sheets Coated with Alkoxysilane-Derived Films" J.Mater.Sci.Lett.12. 724-727 (1993)

K.Izumi：“三官能烷氧基硅烷的水解和涂有烷氧基硅烷衍生薄膜的钢板的耐腐蚀性”J.Mater.Sci.Lett.12。

N.Tohge, H.Tanaka, K.Tadanaga and T.Minami: "Preparation and Characterization of PZT and PLZT Thin Films by the Sol-Gel Process Using Chemically Modified Metal-Alkoxides" J.Mater.Sci.(to be submitted).

N.Tohge、H.Tanaka、K.Tadanaga 和 T.Minami：“使用化学改性金属醇盐通过溶胶-凝胶法制备 PZT 和 PLZT 薄膜并表征”J.Mater.Sci.（待提交）

峠 登: "ゾル-ゲル法によるエレクトロニクス用薄膜の作製と特性" 電気化学. 60. 765-770 (1992)

Noboru Toge：“使用溶胶-凝胶法制备电子薄膜及其性能”电化学 60. 765-770 (1992)。

N.Tohge: "Preparation and Properties of Ferroelectric Thin Films by the Sol-Gel Method (in Japanese)" Science and Technology. 66. 481-486 (1992)

N.Tohge：“溶胶-凝胶法铁电薄膜的制备和性能（日语）”科学与技术。

峠 登: "ゾル-ゲル法による強誘電体薄膜の作製と特性" 科学と工業. 66. 481-486 (1992)

Noboru Toge：“溶胶-凝胶法铁电薄膜的制备和性能”《科学与工业》66. 481-486 (1992)。