Ink-jet printed thin films of conductive polymers such as polyaniline (PANI), poly(3,4-ethylenedioxythiophene) (PEDOT) doped with poly(styrene sulfonate) and polymer dielectric material poly(4-vinylphenol) (PVP) were used to make RC filters. Both high-pass and low-pass filters were tested. The fabrication process and device characteristics of the RC filters have been demonstrated. Degradation of the ink-jet printed RC filters has been investigated, and the results indicate that PEDOT/PSS RC filters are more stable than those made from PANI. (c) 2005 Elsevier Ltd. All rights reserved.