We use optical scatterometry to extract the time evolution of the profile of nanoimprinted lines in low and high molecular mass polymer gratings during reflow at the glass transition temperature. The data are obtained continuously during the anneal using a spectroscopic ellipsometer and analyzed using a rigorous-coupled-wave model. We show excellent agreement of scatterometry results with ex situ measurements of line height by atomic force microscopy and specular x-ray reflectivity. The in situ scatterometry results reveal differences in the shape evolution of the grating lines indiscernible by other methods.
Citation: Applied Physics Letters
Pub Type: Journals
ellipsometry, nanoimprint, optics, polymers, scatterometry, semiconductors