Resonant soft x‐ray scattering and reflectivity study of the phase‐separated structure of thin poly(styrene‐b‐methyl methacrylate) films

Combined soft X-ray scattering and reflectometry techniques promise analysis of polymer thin film domain structure and composition without resorting to chemical modification or isotopic labeling. This work explores the capabilities of these techniques in polymer films of poly(styrene-b-methyl methacrylate) (P(S-b-MMA)). The results demonstrate that the techniques give detailed information on the domain structure of thin films using well-known modeling procedures. Discrepancies were noted between the X-ray optical parameters that are needed to best fit the reflectivity data to the model and the expected parameters. The sources of these discrepancies are discussed in terms of instrument configuration parameters, sample attributes, and, particularly, anisotropy of the chromophore parameters. The results show that fitting the soft X-ray reflectivity data is much more sensitive to these X-ray optical parameters than the soft X-ray scattering data. Nevertheless, fits to both types of data yield quantitative measures of the polymer film's lamellar morphology that are consistent with each other and with literature values. (c) 2012 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2013