Scalable, Alternating Narrow Stripes of PVA Support and Unmodified PEDOT:PSS with Maintained Conductivity using a Single-Step Slot Die Coating Approach.

Slot die coating has been established as an economical approach for deposition of parallel narrow stripes, a constituent pattern feature in many printed device applications. However, the minimum feature size that can be achieved using this approach is constrained by wetting and liquid bridge phenomena at the deposition region. We hypothesize that pattern resolution and process control can be improved by co-depositing a support fluid to stabilize the pattern. Electrically conductive poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) is slot die coated in parallel stripes on flexible poly(ethylene terephthalate) (PET) substrate, without wettability-enhancing dopants or substrate pre-treatment. A miscible liquid phase, polyvinyl alcohol (PVA), is used as the support material. Feature size performance and conductivity of PEDOT:PSS stripe regions are evaluated across a range of process conditions. Narrow PEDOT:PSS stripes produced using our technique range from 400 to 850 µm, and exhibit conduc...