ABSTRACT
We demonstrate glancing-angle deposition of gold on a nanostructured diblock copolymer, namely polystyrene-block-poly(methyl methacrylate) thin film. Exploiting the selective wetting of gold on the polystyrene block, we are able to fabricate directional hierarchical structures. We prove the asymmetric growth of the gold nanoparticles and are able to extract the different growth laws by in situ scattering methods. The optical anisotropy of these hierarchical hybrid materials is further probed by angular resolved spectroscopic methods. This approach enables us to tailor functional hierarchical layers in nanodevices, such as nanoantennae arrays, organic photovoltaics, and sensor electronics.
ABSTRACT
We investigated the spray deposition and subsequent self-assembly during drying of a polystyrene nanoparticle dispersion with in situ grazing incidence small-angle X-ray scattering at high time resolution. During the fast deposition of the dispersion and the subsequent evaporation of the solvent, different transient stages of nanoparticle assembly can be identified. In the first stage, the solvent starts to evaporate without ordering of the nanoparticles. During the second stage, large-scale structures imposed by the breakup of the liquid film are observable. In this stage, the solvent evaporates further and nanoparticle ordering starts. In the late third drying stage, the nanoparticles self-assemble into the final layer structure.
Subject(s)
Nanoparticles/chemistry , Polystyrenes/chemistry , Scattering, Small Angle , Silicon/chemistry , X-Ray Diffraction , Desiccation , Solvents/chemistry , Temperature , VolatilizationABSTRACT
HASE (Highly Automated Sputter Equipment) is a new mobile setup developed to investigate deposition processes with synchrotron radiation. HASE is based on an ultra-high vacuum sputter deposition chamber equipped with an in-vacuum sample pick-and-place robot. This enables a fast and reliable sample change without breaking the vacuum conditions and helps to save valuable measurement time, which is required for experiments at synchrotron sources like PETRA III at DESY. An advantageous arrangement of several sputter guns, mounted on a rotative flange, gives the possibility to sputter under different deposition angles or to sputter different materials on the same substrate. The chamber is also equipped with a modular sample stage, which allows for the integration of different sample environments, such as a sample heating and cooling device. The design of HASE is unique in the flexibility. The combination of several different sputtering methods like standard deposition, glancing angle deposition, and high pressure sputter deposition combined with heating and cooling possibilities of the sample, the large exit windows, and the degree of automation facilitate many different grazing incidence X-ray scattering experiments, such as grazing incidence small and wide angle X-ray scattering, in one setup. In this paper we describe in detail the design and the performance of the new equipment and present the installation of the HASE apparatus at the Micro and Nano focus X-ray Scattering beamline (MiNaXS) at PETRA III. Furthermore, we describe the measurement options and present some selected results. The HASE setup has been successfully commissioned and is now available for users.