Design and Prototyping of a ‘Sweep’ - Coating Method for Generating Thin Films

Abstract

The use of thin films, as in monolayers, has been showing an uptick in applied research such as coatings for biomedical implants as well as in fundamental research such as cell and developmental mechanobiology. Common methods to create thin films of polymers and biomolecules include spin coating, dip coating, microfluidics, soft lithography and dip-pen lithography. In general, current challenges to creating thin films include costly machines, efficiency use of the thin film ‘ink’, output reproducibility, min/max effective surface area, versatility to uniform/gradient generation and potential for micro- and nanopatterning. Hence, the project aims to design and create a prototype that can create a thin film, to begin with, via an alternative method called sweep-coating method. Here, a control panel linked to a microcontroller that can actuate components with a minimal rotation was developed. The idea is that a uniform or a gradient of thin film can be created by ‘sweeping’ the surface of a substrate on the ink. Modelling of the relationship between motor speed and time, independently, on the thin layer formation was generated. This prototype can be further fine-tuned for future applications in biomedical research such as biological interactions on spatiotemporal-controlled interfaces.