Staining-free observation of polymer blend thin films on transmission extreme ultraviolet microscopy

Abstract

Abstract Transmission extreme ultraviolet microscopy is applied to the staining-free observation of a poly(styrene–methyl methacrylate) (PS/PMMA) blend. At a photon energy of 92 eV, the imaginary part of the atomic scattering factor for oxygen, which represents the absorption, is four-times larger than that of carbon, and microstructures can be visualized by the contrast resulting from the presence of oxygen. Based on the signal to noise ratio of the images, we consider the optimum photon energy and sample thickness for common polymer blends. Finally, a practical high contrast of 30% is successfully demonstrated for the PS/PMMA thin film.