\hbox{(Ba,Ca)TiO}_{3} PTCR Ceramics with \hbox{LaNiO}_{3} Thin-Film Electrodes: Preparation and Characterization of the Interface

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• 作者：Trummer ; Bernd ; Fruhwirth ; Otto ; Reichmann ; Klaus ; Herzog ; Gerhard ; Sitte ; Werner ; Holzinger ; Michael
• 关键词：PTCR ; conducting perovskites ; interface ; barrier layer ; mott ; schottky theory
• 刊名：Journal of Electroceramics
• 出版年：2000
• 出版时间：2000
• 年：2000
• 卷：5
• 期：1
• 页码：53-61
• 全文大小：163 KB
• 刊物类别：Chemistry and Materials Science
• 刊物主题：Chemistry
  Optical and Electronic Materials
  Ceramics,Glass,Composites,Natural Materials
  Characterization and Evaluation Materials
  Electrochemistry
  Crystallography
  
• 出版者：Springer Netherlands
• ISSN：1573-8663

文摘

Conductive $\backslash hbox\{LaNiO\}\_\{3\}$ thin film electrodes were deposited by chemical solution deposition (CSD) from nitrate solutions onto polycrystalline $\backslash hbox\{Al\}\_\{2\}\backslash hbox\{O\}\_\{3\}$ and ($\backslash hbox\{Ba,Ca\}\backslash hbox\{)TiO\}\_\{3\}$ PTCR ceramic substrates. The electrical properties of the $\backslash hbox\{LaNiO\}\_\{3\}$ thin film on $\backslash hbox\{Al\}\_\{2\}\backslash hbox\{O\}\_\{3\}$ and of the interface consisting of $\backslash hbox\{LaNiO\}\_\{3\}$ and the semiconductive oxide ceramic were investigated. The deposited $\backslash hbox\{LaNiO\}\_\{3\}$ films were about 250 nm thick and consisted of nanosized particles. The resistivity of the $\backslash hbox\{LaNiO\}\_\{3\}$ film was about $3\; \backslash times\; 10^\{-3\}\backslash \; \backslash Omega\; \backslash hbox\{cm\}$ at 20°C. The PTCR ceramic consisted of μm sized particles and exhibited an electronic resistivity of about 10 Ωcm at 20°C and a steep increase of the resistivity of a few orders of magnitude above the Curie point at about 120°C. The electrical properties of the $\backslash hbox\{LaNiO\}\_\{3\}/\backslash hbox\{PTCR\}$ interface were dominated by the properties of a barrier layer between the PTCR ceramic and the $\backslash hbox\{LaNiO\}\_\{3\}$ electrode. The potential dependence of the impedance indicated that the barrier layer consisted of a depletion layer within the PTCR ceramic, when the flat band potential of $\backslash hbox\{LaNiO\}\_\{3\}$ on the PTCR ceramic at about −250 mV was exceeded. Additionally the formation of an insulating layer at the $\backslash hbox\{LaNiO\}\_\{3\}$ electrode has to be taken into account.