Birnie, Dunbar P. III
Source: Journal of Non-Crystalline Solids, 218,
(1997) p 174-178
Abstract: The flow and evaporation behavior from complex solutions
during spin coating have been measured. Methanol/butanol mixtures where
chosen as a controlled case-study for intensive evaluation. In addition,
a sample sol-gel was evaluated using the same techniques. It was found
that binary solutions had two identifiable thinning regions. At first,
the thinning behavior is governed by the viscosity and evaporation rate
of the starting mixture. However, near the end of the spinning process,
the evaporation of the more volatile component has caused the fluid composition
to change (toward the less volatile solution member). Therefore, the thinning
behavior at the end displays a transition which approaches that of the
pure end-member. The thinning behavior for the sol-gel precursor solution
was linear until quite close to the gelation point, suggesting that further
analysis of sol-gel solutions would be fruitful using this technique.