Wetting of single crystalline and amorphous silicon surfaces: effective range of intermolecular forces for wetting

ABSTRACT

Wetting at nanoscale is a property of a three-dimensional region with a finite length into the solid domain from the surface. Understanding the extent of the solid region effective on wetting is important for recent coating applications as well as for both crystalline and amorphous solids of different atomic ordering. For such a case, we studied the wetting behaviour of silicon surfaces at various crystalline and amorphous states. Molecular distributions of amorphous systems were varied by changing the amorphisation conditions of silicon. Semi-cylindrical water droplets were formed on the surfaces to be large enough to remain independent of line tension and Tolman length effects. Contact angles showed up to 38% variation by the change in the atomic orientation of silicon. Instead of a homogeneous solid density definition, we calculated different solid densities for a given surface measured inside different extents from the interface. We correlated the observed wetting variation with each of these different solid densities to determine which extent governs the wetting variation. We observed that the variation of solid density measured inside a 0.13 nm extent from the surface reflected the variation of wetting angle better for both single crystalline and amorphous silicon surfaces.

KEYWORDS:

• Surface wetting
• single crystalline and amorphous silicon
• molecular dynamics

Acknowledgements

Authors also would like to thank the Center for Scientific Computation at Southern Methodist University.

Disclosure statement

No potential conflict of interest was reported by the authors.

ORCID

Murat Barisik http://orcid.org/0000-0002-2413-1991

Additional information

Funding

This work was supported by the Scientific and Technological Research Council of Turkey (TÜBİTAK) [grant number 217M460] and by the Turkish Academy of Sciences (TUBA) in the framework of the Young Scientist Award Programme (GEBIP).