Because polymers are not in a thermodynamic equilibrium for temperatures below Tg, such as room temperature, they gradually approach equilibrium through free volume relaxation. This phenomenon, called physical aging, implies that the lithographic material is slowly, but continually changing. These modifications can be observed using various techniques: Thermal Analysis, Ellipsometry, IRFT Spectrometry. The influence of physical aging on dissolution rate is clearly demonstrated. The results presented in this paper demonstrate that not only the chemical, but also the physical properties of polymers play an important role in lithographic processes.

Date Published: 1 June 1991
PDF: 9 pages
Proc. SPIE 1466, Advances in Resist Technology and Processing VIII, (1 June 1991); doi: 10.1117/12.46382

Published in SPIE Proceedings Vol. 1466:
Advances in Resist Technology and Processing VIII
Hiroshi Ito, Editor(s)