Inkjet printed PEDOT:PSS for organic devices

Abstract

Printing technology is a low cost technique for the processing of organic electronic devices. Here, we report printing characteristics of poly (3,4-ethylenedioxythiophene) : poly (styrenesulfonate) (PEDOT:PSS), typically used as hole injection/transport layer in various organic devices e.g. organic light emitting diodes, solar cells, and field effect transistors. In this work, we optimize drop spacing and substrate temperature during ink-jet printing of PEDOT:PSS films on rigid (glass) and flexible (PET) substrates. Morphological characterization of the films was performed using optical and scanning electron microscopy. Optical transmittance was measured using UV-Vis spectrophotometer and sheet resistance of the films was measured using four-point probe technique. We find that substrate temperature and drop spacing significantly affect the morphology, in our case decreasing these lead to smooth morphology of the ink-jet printed PEDOT-PSS films.