Evaluating GISAXS data with SAXSanalysis using the BornAgain export
A detailed GISAXS structure analysis of a monolayer of gold nanoparticles with SAXSanalysis and BornAgain.
Grazing-incidence small-angle X-ray scattering is becoming a standard method in the analysis of thin film structures. However, the evaluation of such data sets is still often challenging.
BornAgain (www.bornagainproject.org) is currently the most modern software for the fitting and simulation of GISAXS data. However, detailed knowledge of the beamline setup is required for proper data fitting and analysis. To facilitate the import of these parameters, the Anton Paar SAXSanalysis software offers a direct export function into the BornAgain software. All beamline parameters are automatically transformed into the BornAgain coordinate system. This way users can focus on their samples and application and do not have to worry about the experimental setup.
To precisely assess parameters of a monolayer of gold nanoparticles we performed GISAXS experiment on the Anton Paar SAXSpoint 2.0 system. Data preprocessing was done using the Anton Paar SAXSanalysis software, followed by a detailed analysis with the BornAgain software.
Figure 1 shows the experimental data and Figure 2 shows the corresponding BornAgain fit.
Fig. 1 2D GISAXS pattern of the gold nanoparticle thin film structure.
Fig. 2 Fit of the BornAgain software to the pattern shown in Figure 1.
For the thin film structure, Siffalovic et al.1 found a diameter of approximately 6 nm for the gold parti-cles and hexagonal lattice with a lattice constant of around 8 nm. They determined the lattice constant solely from the q-value of the peak position and argue that this way they might observe a slightly too large lattice constant. From the fit in the BornAgain software we found a lattice constant of 7.8 nm. This well agrees to the suggestion of the original authors that their lattice constant is slightly too large. Furthermore, it demonstrates the power of a full pattern fit within the framework of the Distorted-wave Born approximation (DWBA).
1 K. Vesgo, M. Jergel, P. Siffalovic, M. Kotlar, Y. Halahovets, M. Hodas, M. Pelletta, E. Majkova, SENSOR ACTUAT A-PHYS 241 (2016) 87-95.