| AVS 57th International Symposium & Exhibition | |
| Thin Film | Wednesday Sessions |
| Session TF-WeA |
| Session: | Thin Films: Growth and Characterization |
| Presenter: | T. Hauffman, Vrije Universiteit Brussel, Belgium |
| Authors: | T. Hauffman, Vrije Universiteit Brussel, Belgium E. Tourwé, Vrije Universiteit Brussel, Belgium A. Hubin, Vrije Universiteit Brussel, Belgium H. Terryn, Vrije Universiteit Brussel, Belgium |
| Correspondent: | Click to Email |
In order to form stable self-assembling organic monolayers on numerous substrates, dipping deposition from organic solvents is a widespread technique. However, it is rarely investigated what is the influence of the solvent on the substrate and the molecules which are supposed to be deposited. In this study we present the self assembly of phosphonic acids from an ethanolic solution on aqueous based pretreated aluminium oxides. Following the deposition behavior with XPS and AFM throughout deposition time, it was concluded that the nature of the deposition is random and fluctuating. In order to understand better what is going on, the deposition was followed in situ with odd random phase multisine impedance spectroscopy. This technique gives the opportunity to follow the behavior of the organic molecules as well as the behavior of the buried substrate. It was observed that ethanol adheres on the surfaces, changing the water based chemistry which was obtained through the pretreatment. Furthermore, a competition between the adsorption of the phosphonic acids and ethanol was seen, explaining the non-stable behavior previously analysed with XPS and AFM.
This statement was proven by characterizing ethanol-stabilised aluminium oxide samples during different immersion times. Although here no monolayer was formed, the trend observed corresponded with continuous organic layer growth.