Direct writing of anodic oxides for plastic electronics

Metal oxide thin films for soft and flexible electronics require low cost, room temperature fabrication, and structuring processes. We here introduce an anodic printing process to realize the essential building blocks of electronic circuitry, including resistors, capacitors, field-effect transistors, diodes, rectifiers, and memristors directly on imperceptible plastic substrates. Largely independent on surface properties, we achieve high-quality, few nanometer thin dielectric and semiconducting films even on rough substrates via localized anodisation of valve metals using a scanning droplet cell microscope. We demonstrate printing-like fabrication of 3D multilayer solid-state capacitors with a record-high areal capacity of 4 mu Fcm(-2). Applicable to the whole class of valve metals and their alloys, our method provides a versatile fabrication technique for the circuits that empower the flexible and stretchable electronics of tomorrow. Flexible circuits: anodization makes them all!A simple concept of scanning head-guided anodization is shown to be highly expandable to fabricate various electronic components. A team led by Professor Siegfried Bauer from Johannes Kepler University Linz, Austria develops a universal and patternable printing protocol of anodic oxides for a full range of circuit components for flexible devices. The researchers employ a scanning droplet cell microscope to anodize the pre-deposited thin metal films to form dielectric layers with good control in both lateral dimension and vertical thickness. They demonstrate the versatility of the on-site anodization methods by fabricating oxides-based resistors, diodes, transistors and memristors, and multilayer capacitors with a record-high areal capacity of 4 mu Fcm(-2). The approach is cheap, adaptable, and thus ideal for rapid-prototyping of metal oxides circuits for various applications.