The influence of the technological parameters on the ionic conductivity of samarium doped ceria thin films

Abstract

Sm_0,20Ce_0,80O₂ powder was used for the formation of samarium doped cerium oxide (SDC) thin films using e-beam. Surface area of powder was 34.9 m²/g and particle size – 0.3-0.5 μm. Thin films were deposited using physical vapor deposition system on SiO₂ and Alloy 600 substrates. 2 Å/s – 16 Å/s growth rate and 20 °C – 600 °C substrate temperature were used during the deposition. Ionic conductivity investigation revealed that the maximum ionic conductivity (1.67 S/m) has the thin film deposited on 300 °C temperature substrate using 4 Å/s growth rate. Minimum ionic conductivity (0.26 S/m) has thin film which was deposited on 20 °C temperature substrate using 8 Å/s growth rate. Vacancy activation energies vary in 0.87 eV – 0.97 eV range. Furthermore the calculations of crystallite size revealed that crystallite size increases with increasing substrate temperature: from 7.50 nm to 46.23 nm on SiO₂ substrate and from 9.30 nm to 44.62 nm on Alloy 600 substrate. Molar concentration of samarium in initial evaporated material is 19.38 mol% and varies from 11.37 mol% to 21 mol% in formed thin films depending on technological parameters.

DOI: http://dx.doi.org/10.5755/j01.ms.21.1.5700