Biancun Xie, Madhavan Swaminathan, et al.
EMC 2011
Variations of the thermal expansion coefficient of thin polyimide films as a function of film thickness (40-260 nm) have been measured by monitoring film thickness as a function of temperature using X-ray reflectivity from samples of poly(pyromellitic dianhydride oxydianiline) (PMDA-ODA) films spin-cast onto silicon wafers. The effective expansion coefficient of the film decreases with decreasing thickness and is consistent with a bilayer model in which an interfacial region of constant thickness is formed for each film. The expansion coefficient of this surface or interfacial region is less than one-third the coefficient of the interior of the films. A simple method is described whereby the thermal expansion coefficient may be determined by reflectivity.
Biancun Xie, Madhavan Swaminathan, et al.
EMC 2011
Imran Nasim, Melanie Weber
SCML 2024
Gregory Czap, Kyungju Noh, et al.
APS Global Physics Summit 2025
Julian J. Hsieh
Journal of Vacuum Science and Technology A: Vacuum, Surfaces and Films