We examine the influence of viscoelastic effects on the stability of nanoimprinted polymer films. The decay of features for polymers below the critical entanglement molecular mass at elevated temperatures is determined by simple surface tension and the film viscosity. By contrast, high molecular mass (entangled) polymer patterns under similar conditions exhibit a rapid elastic deformation, followed by an Andrade creep regime of plastic deformation and finally fluid flow at long times. We conclude that these viscoelastic effects have a profound effect on the structural stability of nanoimprinted polymer structures and these nonlinear effects must be considered in the development of nanoimprinting applications.
Citation: Advanced Materials
Pub Type: Journals
critical dimension, nanoimprint lithography, nanotechnology, patterning, small angle scattering, stability, stress, viscoelasticity, X-ray reflectivity