Spin-echo neutron reflectivity on diblock-copolymer films

SERGIS (Spin-Echo Resolved Grazing Incidence neutron Scattering) is a recently developed novel neutron scattering technique which we employ at the new neutron/X-ray reflectometer N-REX+ at FRM II. In contrast to conventional scattering methods, SERGIS measures the lateral structure and morphology of surfaces and thin film systems in real space. The spatial resolution is achieved by measuring the total polarization of the scattered beam, without the usual need to collimate the beam in the direction of interest. Therefore SERGIS combines a high neutron flux with the ability to characterize structures from the nanometer scale up into the micron range, and can thus yields novel information about both equilibrium and time-dependent phenomena on these length scales. As an example, we employ SERGIS to study morphologies produced by dewetting phenomena in thin polymer films. These experiments are complemented by detailed atomic force microscopy investigations. First results on thin diblock-copolymer films will be presented. (orig.)