One step deposition of PEDOT films by plasma radicals assisted polymerization via chemical vapour deposition

Abstract

The careful control of the electrode interface in organic devices is one of the key factors that strongly affects the application of semiconducting polymers to a wide range of organic devices. In this work, a novel vapour phase technique, named plasma radicals assisted polymerization via chemical vapour deposition, is presented and studied to deposit intrinsically conducting polymer films by combining the advantages of current CVD techniques. This innovative concept is based on the concomitant but physically separated injection of low-energy plasma radical initiators and monomer molecules into the deposition chamber where the temperature and the pressure are controlled, which allows the uniform deposition of films on a large surface. As a case study, poly(3,4-ethylenedioxythiophene) synthesis was successfully carried out with an improved growth rate of 2 times, compared to established vapour phase synthesis technologies. Films stable over one year show conductive properties in the range of a few S cm⁻¹, thereby opening avenues for the large scale manufacturing of functional and stable organic thin films with tailored interfaces.