A commercially available water-soluble starch derivative was used as the
sole organic precursor in the Liquid-Mix synthesis of mixed-cation oxide
powders and thin films. The acidified polymer (by nitric acid) was able to
complex metal ions through the carboxylate ligands. Loosely agglomerated
fine powders as well as dense thin films of complex oxides have been
prepared using the same type of polymer. Oxide powders of Cr-doped lanthanum
aluminate and yttrium aluminum garnet both crystallized in a single step,
without forming any intermediate or second phases, when the amorphous resin
intermediates were calcined at 650°C and 750°C for 2 hours, respectively. It
was demonstrated that nitric acid could effectively reduce the viscosity of
the polymer-nitrate solution to make it suitable for spin coating process.
Dense thin films of Y(8 mol%)-doped ZrO2 were formed on Si and
A12O3 substrates by spin coating the polymeric
solution and heating at temperatures below 1000°C.