Zirconia thin films were deposited on different substrates by reactive
r.f, magnetron sputtering. It was found that zirconia layers grew pre
ferentially in the (200) direction with a columnar microstructure that
is independent of the oxygen flow, argon to oxygen flow ratios and sp
uttering pressure. On the other hand the substrate roughness clearly a
ffects the orientation of zirconia. Distinct changes were observed in
the case of heated substrates. The heating of the substrates does not
change the form of the zirconia, but strongly influences its orientati
on. When the substrate temperature increases, the crystallographic ori
entation gets more and more random, typically for the polycrystalline
state. A decrease in the optical transmittance and an increase in the
colour intensity of the layers with an increase in the substrate tempe
rature was also found. As is shown, the oxygen non-stoichiometry of th
e zirconia is responsible for these changes.