In-situ investigations of condensation, nucleation and growth of metal films and nanostructures on organic surfaces during sputter deposition

• Applicants: Professor Dr. Franz Faupel; Professor Dr. Peter Müller-Buschbaum; Professor Dr. Stephan Volkher Roth
• Subject Area: Synthesis and Properties of Functional Materials
• Term: from 2013 to 2021
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 238058777

While sputtering of metal coatings on polymers is well established, the early deposition stages are still not well understood due to the complex nature of the deposition process. However, particularly the sub-monolayer regime with its transient 2D nanogranular and ramified structures is of great interest for hosts of emerging applications ranging from plasmonics through sensors to organic photovoltaics. These applications require precise control and understanding of the sputter deposition of sub-monolayer metallic nanostructures on polymer surfaces prior to the formation of a closed film. In the current funding period, the early deposition stages were monitored for selected metal-polymer systems in real time with high special and temporal resolution by means of grazing incidence small angle scattering (GISAXS) in a specially designed mobile sputter chamber at the MiNaXS/P03 instrument of the synchrotron radiation source PETRAIII. The unique results, combined with modelling and various other in situ and ex-situ techniques as well as computer simulations have provided a profound understanding of sub-monolayer sputter deposition. In the 2nd funding period, even more complex processes such as deposition of 2D nanogranular metal alloy films and sputtering onto block copolymer films will be studied. For nanoscale metal alloy structures, marked deviations from bulk phase diagrams are to be expected. This will inter alia allow in-situ observation of phase separation in growing complex nanostructures. Block copolymer substrates will give rise to tailored nanostructures, because they involve selective wetting and nucleation on one of the blocks at different tailorable length scales. At a later stage, glancing-angle deposition will provide another exciting subject of investigation.

• DFG Programme: Research Grants
• Cooperation Partner: Professor Dr. Michael Bonitz