Thin Solid Films, Vol.457, No.2, 258-263, 2004
Processing and characterization of yttrium-stabilized zirconia thin films on polyimide from aqueous polymeric precursors
Low-temperature deposition of dense, nanocrystalline yttrium-stabilized zirconia (YSZ) thin films on polyimide (PI) substrates is illustrated using an aqueous polymeric precursor spin-coating technique. The polymeric precursor uses low-cost materials, is water-soluble and the viscosity and cation concentrations can be easily adjusted in order to vary the film thickness from 0.02 to 0.3 mum. Due to the use of water as the solvent in the YSZ precursor and the hydrophobic nature of the PI surface, surface modification processes were utilized in order to improve the wetting characteristics. Surface modification of PI substrates using wet chemical and oxygen plasma techniques led to a decrease in the precursor contact angle, and ultimately allowed for uniform film formation on both bulk and thin film PI substrates. Scanning electron microscopy, transmission electron microscopy and UV/Vis absorption illustrate that near full-density nanocrystalline thin films of YSZ can be produced at temperatures as low as 350 degreesC. Thermogravimetric analyses illustrate that the PI substrate does not undergo any weight loss up to these temperatures. (C) 2003 Elsevier B.V. All rights reserved.