Fabricating dielectric elastomer transducer electrodes using micro atmospheric plasma jet

Dielectric elastomer transducers (DET) are demonstrating exciting potential in many fields, including healthcare, wearable technology, and soft robotics. The electrode layers within these are paramount to their effectiveness, with the demands on these elements likely to increase further as we strive for stretchable electrodes with even greater performance, higher geometric complexity, and greater degrees of actuation or sensing. However, there is a disparity between the demands and ambitions of new DET devices and the capabilities of the current fabrication techniques. Common manufacturing approaches fall into two categories, template-based (e.g screen printing and lithography) and additive methods (e.g. 3D printing). The former limits the design complexity and is poorly suited to low production volumes, prototyping, and device personalization. While the latter overcomes these issues, it is characterized by constraints on printable materials, low material throughput, and limited resolution. We present a novel fabrication approach for DET electrodes, using a micro atmospheric pressure plasma jet to selectively induce hydrophilicity on a silicone elastomer layer. Polar fluids containing dispersed conductive particles self-align with the hydrophilic pattern, removing the need for precise spatially controlled deposition. Furthermore, we demonstrate a dynamically tunable resolution from 45μm to 1200μm through variation driving voltage and frequency. Using a bespoke computer-controlled apparatus we present the opportunity for the rapid and flexible fabrication of the next generation of DETs capable of utilizing a wider range of materials and achieving greater feature resolution, conducted by an automated and scalable process. We showcase the approach by fabricating a functional dielectric elastomer actuator.