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Utilization of Industrial Inkjet Technologies for the Deposition of Conductive Polymers, Functional Oxides and CNTs Wolfgang Voit1,2, Ingo Reinhold1, Werner Zapka1, Lyubov Belova2 and K.V. Rao2 1 XaarJet AB, Elektronikhöjden 10, SE-17526 Järfälla, Sweden 2 Department of Materials Science-Tmfy-MSE, Royal Institute of Technology, SE-10044 Stockholm, Sweden ABSTRACT Printing of functional materials requires reliable deposition processes. This work describes the development of printing processes for selected functional materials utilizing industrial-type inkjet printheads. A well-controlled printing process with fluids containing the conductive polymer poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) is presented, allowing linear printing speeds of up to 0.35 m/s in single-pass, and smallest line width of approximately 40 µm when printing 7 pL drop volumes. In addition reliable processes for producing ZnO-based films, which enable novel applications for electronic and UV-sensitive devices, and for printing of conductive carbon nanotube layers are shown. INTRODUCTION Apart from its traditional use in graphical printing, inkjet printing is emerging as a versatile process for the deposition of various functional materials. While the major advantage of inkjet techniques for application areas like printed electronics is the ability to produce patterned layers in a truly digital process, there is often still a struggle to utilize these techniques for high throughput and large-area applications. Many developments involving inkjet printing are carried out in a lab-scale environment and are strongly limited in printing speed, productivity and reliability of the printing processes. While printing with single-nozzle heads or with a large number of multiple passes is a viable approach for lab samples, it is not suitable for production environments of printed electronics. For such applications, multi-nozzle printheads and highly reliable printing processes are needed that allow for single-pass printing in roll-to-roll processes. This paper focuses on the development of reliable methods for the deposition of different functional materials with industrial inkjet printheads. In particular, a process to print highly conductive formulations of the conjugated polymer PEDOT:PSS with the latest models of Xaar inkjet printheads was developed. PEDOT:PSS is an attractive material for printed electronics, as it combines high transparency with reasonably high electrical conductivity. Potential applications range from the use as transparent conductive coatings, as hole injection layers for OLEDs and organic photovoltaics, or as electrode material for organic transistors [1] and organic memories [2]. We demonstrated earlier the feasibility of using inkjet printing of PEDOT:PSS dispersions for device manufacturing [2, 3]. The lab-type printing processes in this previous work were developed further towards a reliable high-throughput process in the present study by utilizing Xaar 1001 printheads with continuous ink through-flow. The