Templating Electrohydrodynamic Instabilities with Thermocapillary Multidewetting

Thermocapillary dewetting of liquids and molten films has recently emerged as a viable alternative to conventional microprocessing methods. Its dependence on fundamental thermal gradients allows it to be applied to various combinations of materials, including metals and polymers, with sufficiently different melting points. Here, we investigate the application of focused laser spike (FLaSk) multidewetting to direct electrospray deposition. Electrospray deposition utilizes narrow dispersion microdroplet sprays generated by high voltage to deposit micro/nanocoatings. Due to the charged nature of these sprays, they are sensitive to the ability of the spray target to dissipate and redistribute charge on arrival. By the independent greyscale pattering of insulators and conductors through FLaSk, it is possible to create complex masks to template paths to ground for electrospray deposition. These templates can act as both stencils and lenses to trigger and enhance electrohydrodynamic instabilities. The net result is both a fundamental platform for the study of these phenomena and, by crosslinking of the templated fluids, a means of patterning desired structures.