Precursor Decomposition, Microstructure, and Porosity of Yttria Stabilized Zirconia Thin Films Prepared by Aerosol-Assisted Chemical Vapor Deposition

Microstructures of yttria stabilized zirconia thin films deposited by aerosol assisted chemical vapor deposition (AA-CVD) are correlated with the thermal decomposition behavior of the corresponding metal precursors, zirconium and yttrium 2,4-pentanedionate. Process conditions of AA-CVD are investigated with the aim of producing dense and compact YSZ thin films for applications as gas-tight electrolyte. Based on systematic cross sectional scanning transmission electron microscopy (STEM) investigations and conductivity measurements, the development of percolating nanoporosity is observed in samples prepared at temperatures between 350 degrees C and 600 degrees C at standard solution throughput. Compact columnar thin films with bulk conductivity are obtained at 600 degrees C by reducing the metal content of the precursor solution and at 450 degrees C by reducing the solution throughput.