Inkjet Printing PEDOT:PSS using Desktop Inkjet Printer

PEDOT:PSS has been used recently into many organic-based devices in order to help charge transfer and improve efficiency of the devices. PEDOT:PSS exhibit various interesting properties. It posses relatively good electrochemical, ambient, and thermal stability of its electrical properties as compared with the other polythiophenes. One aim of manufacturing organic-based device is to lowering the fabrication cost. Due to PEDOT:PSS's stability, it is possible to pattern PEDOT:PSS using inkjet printing. We found that using the CANON IP4500 desktop inkjet printer, the structure of 150 micron could be patterned on PET substrate. By modifying the surface properties of the substrate, the structure of 20 micron could be achieved. The conductivity of inkjet printed PEDOT:PSS could be further enhanced by annealing at 80 C. The conductivity could be 3 times improved. The morphology of the annealed PEDOT:PSS was further investigated using atomic force microscopy(AFM) and the cause for conductivity enhancement could be explained via localization length extension in variable range hopping theory.