Surfaces With Roughness Gradient and Invariant Surface Chemistry Produced by Means of Gas Aggregation Source and Magnetron Sputtering
Abstract
Surfaces whose properties change gradually along the sample length, so-called gradient surfaces, are highly interesting for fundamental studies focused on the interaction between biomolecules or cells and surfaces. In this study, we investigate simple, vacuum-based strategy for fabrication of surfaces with gradient nanoroughness and wettability.
This approach is based on the application of gas aggregation source of nanoparticles combined with the magnetron sputtering of poly(tetrafluoroethylene). It is shown that this technique makes it possible to produce coatings with invariant surface chemistry, but with gradient roughness in the range 0.5-20 nm and wettability gradient that ranges from 100 degrees up to 150 degrees, i.e., coatings with hydrophobic to superhydrophobic character.