Lecture Andreas Meyer
|14 October 2011||FWN-Building 5118.-152, Nijenborgh 4, 9747 AG, Groningen|
|Speaker:||Dr. Andreas Meyer|
Institut für Physikalische Chemie, UniversitätHamburg, Germany
|Title:||Directed self-assembly of Block Copolymers and Nanocomposites on Surfaces|
|Date:||Fri Oct 14, 2011|
|Telephone:||+31 50 363 6768|
Controlling the structure of matter at the nanometer scale and assemble nanoparticles into arrays and networks in a controlled manner is the key to new technologies. Nanosphere lithography is one of the most simple and effective methods for the preparation of large-area, two-dimensional nanostructure arrays. Inorganic precursors of the desired nanoparticles were introduced into micelles. By bringing them onto surfaces they form lateral hexagonal long-range ordered structures. The nanoparticles have tuneable diameters and distances between 10 and 100 nm, controlled by the block lengths of the initial polymer.
Magnetic nanostructure arrays can be created using these monolayers as sputtering masks. The number of preparation steps is kept as low as possible to simplify the formation of the nanostructure array. The structure of the cores is transferred into the film via ion milling under normal incidence. The generated dots were made of (Co/Pt)2-multilayers. They show different magnetic behaviour, depending on their size, interparticle distance and milling time.
Directed self-assembling over large distances of nanoparticles and nano-composites can be reached by topographically or chemically pre-structured substrates. They are easily manufactured by lithography and reproducible with soft imprint lithography. Therefore, we developed a method to use optical storage media (CD, DVD, Blue-Ray) as master pattern for the creation of directed, long range ordered nanoparticle arrays.
AFM and SEM-investigations show highly ordered particles in large domains. Corresponding GISAXS patterns show strong hexagonal diffraction peaks. By analyzing the scattered intensity, we were able to determine the lateral scales of the structure. Furthermore, simulations of the diffraction patterns were successful generated and models with precise length scale parameters were calculated.
|Last modified:||22 October 2012 2.30 p.m.|