Electronic properties of junctions between aluminum and doped poly (3,4-ethylenedioxythiophene)

Abstract

Metal contacts to poly(3-,4-ethylenedioxythiophene) doped either with large polymeric anions such as poly(styrenesulphonate) or small anions like ClO 4 − have been studied by means of electrical characterization. The current-voltage characteristics and complex impedance spectroscopy show the poly(3-,4-ethylenedioxythiophene) (PEDOT) (large anion)/Al contacts to be described by an insulating layer in series with a layer depleted of charge carriers. With the PEDOT(small anion)/Al contacts, no interfacial insulating layer is detected in the measurements, but a depletion layer is observed.