Measurement of trap level near the electrode and dielectric thin film boundary by TSC and TL

利用 TSC 和 TL 测量电极和电介质薄膜边界附近的陷阱能级

• 批准号: 10650664
• 负责人: SALURAI Osamu
• 金额: $ 2.11万
• 依托单位: Tokyo Institute of Technology
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1998
• 资助国家: 日本
• 起止时间: 1998 至 1999
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-10650664/
• 关键词: led titanate; barium titanate; thermo stimulated current; trap level; phase transition; leak current; ferroelectric films

Fatigue and leak current of lead titanate and barium strontium titanate films for randam access memory devices were caused by metal ion defects, oxygen vacancy and trapped charge carriers. Objectives of these studies are clarified the relations these defects in the film and TSC peaks related to phase transitions and dielectric relaxation.Polarized barium strontium titanates released electric charges with phase transition from ferroelectric to ferrielectric phase. At phase transition temperature, another new TSC peak was observed except peaks related to phase transition. It was clarified that new peak was generated by relaxing trapped charges in the film.Furthermore, effect of heat treatment for lead titanate films, having relatively low resistivity and leaky property, was studied. Maximum polarization (Pm) of film was lowered and resistivity was increased from 1.2X10ィイD1-8ィエD1 to 3.0X10ィイD1-8ィエD1Ωcm slightly. P-E curves of film were asymmetry with applied electric field. TSC peaks were observed at 74 and 130℃, trap level is 0.45 and 0.52eV respectively for heated films. Otherwise no peak was observed for heated film. It seemed that TSC peaks highly depended on relaxation of electric charge. Leak current properties of films were improved by heating for decreasing the electric charge.

随机存取存储器用钛酸铅和钛酸锶钡薄膜的疲劳和漏电流是由金属离子缺陷、氧空位和捕获载流子引起的。这些研究的目的是澄清这些缺陷的薄膜和TSC峰有关的相变和介电弛豫的关系。极化钛酸钡锶释放的电荷由铁电相转变为铁电相。在相变温度下，除了与相变相关的峰外，还观察到另一个新的TSC峰。结果表明，新峰的产生是由于薄膜中被困电荷的弛豫。此外，还研究了热处理对具有较低电阻率和漏性的钛酸铅薄膜的影响。膜的最大极化率（Pm）降低，电阻率由1.2X10 μ l l -8 μ l l - D1略微提高到3.0X10 μ l l -8 μ l - D1Ωcm。薄膜的P-E曲线与外加电场不对称。加热膜在74℃和130℃时出现TSC峰，捕获能级分别为0.45 ev和0.52eV。否则，加热膜没有观察到峰。TSC峰似乎高度依赖于电荷的弛豫。通过加热降低电荷，提高了薄膜的漏电流性能。

项目成果

Daisuke NAGANO: "Electrical Properties and Crystal Structures of Semiconductive Nb-doped BaTiOィイD23ィエD2 Thin Film Prepared by MOCVD"Key Engineering Materials (Electroceramics in Japan I). 157-158. 167-174 (1999)

Daisuke NAGANO：“MOCVD 制备的半导体 Nb 掺杂 BaTiO2 薄膜的电性能和晶体结构”关键工程材料（日本电陶瓷 I）167-174（1999）。

Daisuke NAGANO: "Electrical Properties and Crystal Structures of Semiconductive Nb-doped BaTiO_3 Thin Film Prepared by MOCVD"Key Engineering Materials (Electroceramics in Japan I). 157-158. 167-174 (1999)

长野大辅：“MOCVD制备半导体掺铌BaTiO_3薄膜的电性能和晶体结构”关键工程材料（日本电陶瓷I）。

Tung-Jung Wu: "Reduction of Leakage Current in PbtiO_3 Film Fabricated by MOCVD"Key Engineering Materials (Electroceramics in Japan II). 169-170. 123-126 (1999)

吴东荣：“减少MOCVD制备的PbtiO_3薄膜中的漏电流”关键工程材料（日本电陶瓷II）。

Tung-Jung Wu: "Reduction of Leakage Current In PbTiOィイD23ィエD2 Film Fabricated by MOCVD"Key Engineering Materials (Electroceramics in Japan II). 169-170. 123-126 (1999)

Tung-Jung Wu：“减少 MOCVD 制造的 PbTiO2D23​​D2 薄膜中的漏电流”关键工程材料（日本电陶瓷 II）169-170（1999）。