%0 Journal Article
%A Busch, P.
%A Rauscher, M.
%A Moulin, J.-F.
%A Müller-Buschbaum, P.
%T Debye-Scherrer rings from block copolymer films with power-like order
%J Journal of applied crystallography
%V 44
%@ 0021-8898
%C Copenhagen
%I Munksgaard
%M PreJuSER-14703
%P 370 - 379
%D 2011
%Z CHESS is a national user facility supported by the National Science Foundation and the National Institutes of Health/National Institute of General Medical Sciences under award No. DMR-0225180. We thank Sita Krishnan for the preparation of the semifluorinated diblock copolymer sample. PMB acknowledges financial support by the Deutsche Forschungsgemeinschaft in project No. MU1487/6.
%X The powder-like orientation of lamellar domains in thin films of the diblock copolymer polystyrene-block-poly(methyl methacrylate) is investigated using grazing-incidence small-angle X-ray scattering (GISAXS) and grazing-incidence small-angle neutron scattering (GISANS). Conventional monochromatic GISANS and GISAXS measurements are compared with neutron time-of-flight GISANS. For angles of incidence and exit larger than the critical angle of total external reflection of the polymer, Debye-Scherrer rings are observed. The position of the Debye-Scherrer rings is described quantitatively based on a reduced version of the distorted-wave Born approximation. A strong distortion of the ring shape is caused by refraction and reflections from the film interfaces. Close to the critical angle, the ring shape collapses into a banana shape.
%K J (WoSType)
%F PUB:(DE-HGF)16
%9 Journal Article
%U <Go to ISI:>//WOS:000288758500014
%R 10.1107/S0021889810053823
%U https://juser.fz-juelich.de/record/14703