Electrical behaviour of yttria-doped zirconia (YSZ) in the metal-insulator-metal thin film structure

• Published in: Journal of materials science letters Vol. 12; no. 16; pp. 1306 - 1308
• Main Authors: SALY, V, CHROMIK, S
• Format: Journal Article
• Language: English
• Published: Dordrecht Kluwer Academic Publishers 01-01-1993
• Subjects: Condensed matter: electronic structure, electrical, magnetic, and optical properties; Condensed matter: structure, mechanical and thermal properties; Diffusion in solids; Electronic structure and electrical properties of surfaces, interfaces, thin films and low-dimensional structures; Electronic transport in interface structures; Exact sciences and technology; Metal-insulator-metal structures; Physics; Self-diffusion and ionic conduction in nonmetals; Transport properties of condensed matter (nonelectronic); Frequency dependence; Zirconium oxides; Ionic conductivity; Yttrium additions; MIM junctions; Experimental study; Monoclinic lattices; Permittivity; Activation energy; Molybdenum; Optical conductivity
• ISSN: 0261-8028; 1573-4811
• DOI: 10.1007/BF00506346

The high ionic conductivity of doped ZrO2 at elevated temperatures is exploited for solid electrolyte applications. The conductivity can be higher for the same temperatures if the ZrO2 is prepared in the form of a thin film, and thin film ZrO2 devices can, therefore, be operated at lower temperatures. Thin film metal-insulator-metal (MIM) structures were prepared by electron beam evaporation using YSZ thin film and Mo metal, and the electrical properties were characterised using the electric modulus formalism method. It was found that the conductance of the Mo-YSZ-Mo structure increases with increasing frequency in the range 10-100000 Hz; the conductance curves are shifted to higher frequencies with increasing temperature. The electric modulus exhibits peaks which appear at higher frequencies as the temperature increases. The frequency dependencies of the real and imaginary parts of the complex dielectric permittivity are shown; the plot is shifted to higher frequencies with increasing temperature. Calculation of activation energies was performed. The frequency dependencies of the complex permittivity parts suggests that in the Mo-YSZ-Mo structure (when YSZ is monoclinic), a "hopping" mechanism of conductivity dominates in the frequency and temperature ranges studied. The concentration of mobile carriers does not change at temperatures in the region 125-225 C. 8 refs.