Surface-tension driven self-assembly of microchips on hydrophobic receptor sites with water using forced wetting

Abstract

This letter reports waterdroplet self-alignment methods for self-assembly of microchips on hydrophobic receptor sites in ambient air environment. It is an open question if lyophobic receptor site of the self-alignment medium can be used for self-assembly. We investigate this question using both numerical simulation and experimental studies on hydrophobic receptor sites (advancing contact angle of 118°) with superhydrophobic substrate (contact angle of 180°). We demonstrate that self-alignment is possible using two forced wetting methods: (a) introducing an excessive amount of water and (b) applying external pressure. The results suggest that surface-tension driven self-alignment can be applied in a wider combination of materials and mediums.