The P03 beamline, also called the microfocus and nanofocus X-ray scattering (MiNaXS) beamline, exploits the excellent photon beam properties of the lowemittance source PETRA III to provide a microfocused/nanofocused beam with ultra-high intensity for time-resolved X-ray scattering experiments. The beamline has been designed to perform X-ray scattering in both transmission and reflection geometries. The microfocus endstation started user operation in May 2011. An overview of the beamline status and of some representative results highlighting the performance of the microfocus endstation at MiNaXS are given.

We present a real-time study of the nanostructuring and cluster formation of gold nanoparticles deposited in aqueous solution on top of a pre-structured polystyrene colloidal thin film. Cluster formation takes place at different length scales, from the agglomerations of the gold nanoparticles to domains of polystyrene colloids. By combining in situ imaging ellipsometry and microbeam grazing incidence small-angle x-ray scattering, we are able to identify different stages of nanocomposite formation, namely diffusion, roughness increase, layer build-up and compaction. The findings can serve as a guideline for nanocomposite tailoring by solution casting.

The influence of nanoparticles on the domain orientation in a particle co-operated self-assembly process in thin diblock copolymer films is investigated toward the preparation of ordered magnetic nanoparticle arrays. Thin films are prepared from a mixture of chemically masked iron oxide nanoparticles and a polystyrene-block-poly (methyl methacrylate) diblock copolymer. The resulting nanostructures are investigated with grazing incidence small-angle X-ray scattering, atomic force microscopy and scanning electron microscopy. Nanoparticles arrange themselves spontaneously inside the upright cylindrical domains due to the selective affinity to the poly (methyl methacrylate) minority phase during the microphase separation process and due to the balance of the surface free energies between the polymers and the nanoparticle coating after annealing. The incorporation of the nanoparticles inside the cylindrical domains increases the diameter of the cylindrical domains and the distance between two neighboring domains. A spatially ordered arrangement of magnetic nanoparticles is observed below a critical concentration of 0.2 vol % for the investigated molecular weight of 77 kg/mol.

Diblock copolymer nanostructures with metal oxide nanoparticles are prepared on solid supports by spin-coating. The maghemite nanoparticles (Fe 2 O 3 ) are masked with grafted polystyrene chains to allow a tailored positioning on top of nanostructures created by the symmetric polystyrene-block-polyisoprene diblock copolymer. Film thickness and lamellar thickness of the diblock copolymer are smaller than the nanoparticles diameter to prevent the particles from being embedded inside the polymer superstructure. Nanostructures without nanoparticles are compared with structures with up to 30% nanoparticles content. The structural analysis is based on atomic force microscopy and grazing incidence small-angle X-ray scattering. The observed structures are explained in the framework of a retarded dewetting process preceding microphase separation. With increasing nanoparticle concentration the structural type changes from droplets into a continuous structure and covers typical lengths between 50 and 195 nm. Above a critical concentration cluster formation out of nanoparticles is present in coexistence with isolated nanoparticles and dominates structure creation.

The installation of large scale colloidal nanoparticle thin films is of great interest in sensor technology or data storage. Often, such devices are operated at elevated temperatures. In the present study, we investigate the effect of heat treatment on the structure of colloidal thin films of polystyrene (PS) nanoparticles in situ by using the combination of grazing incidence small-angle X-ray scattering (GISAXS) and optical ellipsometry. In addition, the samples are investigated with optical microscopy, atomic force microscopy (AFM), and field emission scanning electron microscopy (FESEM). To install large scale coatings on silicon wafers, spin-coating of colloidal pure PS nanoparticles and carboxylated PS nanoparticles is used. Our results indicate that thermal annealing in the vicinity of the glass transition temperature T(g) of pure PS leads to a rapid loss in the ordering of the nanoparticles in spin-coated films. For carboxylated particles, this loss of order is shifted to a higher temperature, which can be useful for applications at elevated temperatures. Our model assumes a softening of the boundaries between the individual colloidal spheres, leading to strong changes in the nanostructure morphology. While the nanostructure changes drastically, the macroscopic morphology remains unaffected by annealing near T(g).