Surface Tension-Driven Flows for Convective Deposition

Convective deposition, traditionally driven by evaporation of a solvent from a thin film that results in well-ordered particle arrays from suspension, is performed under various conditions that result in surface tension gradients. This includes the resulting gradient in temperature when heating the substrate, concentration graditent of added surfactant, and concentration gradient when using a binary solvent of ethanol and water. In each case, these surface tension gradients can result in flow profiles and deposition modes that vary greatly from traditional convective deposition. Resulting ultra-fast deposition of well-ordered particle monolayers and streaking instabilities will be explained in terms of these surface tension gradients, breaking previous paradigms surounding convective deposition.