Multiple-scaled polymer surfaces investigated with micro-focus grazing-incidence small-angle X-ray scattering

We show that a position-sensitive sample surface information of multiple-scaled polymer films is successfully addressed with micro-focus grazing-incidence small-angle X-ray scattering (μ-GISAXS). From the analysis of the diffuse scattering without further model assumptions the length scale of the heterogeneous structures is determinable. The method is illustrated by an example of two-step dewetted polystyrene (PS) films exhibiting droplets on a nano scale in coexistence with mesoscopic drops. The results are compared to scanning force microscopy measurements. As compared to the conventional transmission geometry using the same micro-focus optics the resolvable length scale is increased by one order of magnitude.