Quantitative analysis of lamellar structures in brush polymer thin films by synchrotron grazing-incidence X-ray scattering

Abstract

In this study, a grazing-incidence X-ray scattering (GIXS) formula was derived for lamellar structures formed in thin films supported on substrates, and a comprehensive numerical analysis was performed using the scattering formula. A quantitative analysis was conducted of lamellar structures formed in nanometre-scaled thin films of a brush polymer, poly[oxy( n -decylthiomethylenyl)ethylene], supported on silicon substrates, by GIXS measurements during cooling and subsequent heating, and data analysis was performed using the scattering formula. This analysis provided details (long period, sub-layers and their thicknesses, volume fraction, bristle paracrystal distortion factor, and orientation) of the lamellar structure with varying temperature that are not easily obtained using conventional techniques. Moreover, a molecular structure model and electron density profiles were established.