The glass transition temperature (T
g) of thin polystyrene (PS) films supported on silicon wafers
with
oxide layers of varying thickness was characterized by the temperature
dependence of the film thickness using ellipsometry. This allowed
us to uncover how a long-range interaction affects the T
g of polymer films. As previously reported using a variety
of methods, the T
g decreased with decreasing
film thickness. However, the extent was not the same among the reports.
In this study, we found that the T
g attenuation
of a PS film of a given thickness was dependent on the oxide layer
thickness of the silicon wafer via the long-range interaction.