Microstructure Development in Unsupported Thin Films
To better understand the role of the substrate in the microstructural evolution of thin films, unsupported nanocrystalline yttrium-stabilized zirconia (ZrO2:16%Y or YSZ) films were examined as a function of temperature and annealing time. Grain growth, texturing, and pinhole formation were measured using transmission electron microscopy (TEM) and electron diffraction. Films were produced and subsequently annealed on metallic grids using a previously developed technique that results in near full density films at low annealing temperatures. Microstructural evolution in these films was unique compared with constrained films. Grains were found to spheroidize much more readily, ultimately resulting in the formation of porosity and pinholes. Grain growth was found to stagnate at a size particular to each annealing temperature, presumably due to the effects of Zener pinning. It is proposed that the lack of substrate strain and confinement effects allows for the dominance of surface energetics with respect to microstructural evolution.
B. P. Gorman and H. U. Anderson, "Microstructure Development in Unsupported Thin Films," Journal of the American Ceramic Society, John Wiley & Sons, Dec 2004.
Materials Science and Engineering
Missouri. Department of Economic Development
Keywords and Phrases
Microstructure; Thin films
Article - Journal
© 2004 John Wiley & Sons, All rights reserved.