Organic low voltage rewritable memory device based on PEDOT:PSS/f-MWCNTs thin film

We report on devices constructed using a small quantity (⩽0.01 wt.%) of functionalized multiwalled carbon nanotubes (f-MWCNTs) embedded in a conducting polymer (poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate), PEDOT:PSS) matrix and aluminum top electrodes, prepared on indium-tin-oxide (ITO) substrates. Our ITO/(PEDOT:PSS + f-MWCNTs)/Al devices show current bistability. The low resistance ON-state, as well as the high resistance OFF state, retain the information for hours and are stable after hundreds of write–read–erase–read (WRER) cycles, being potentially interesting for erasable and rewritable volatile memory device applications. Moreover, the operation voltages used for performing these WRER cycles are very low. The threshold voltage for OFF to ON switching can be adjusted changing the f-MWCNTs concentration. Our results suggest that the nanotubes are necessary for the production of an inhomogeneous electric field playing a role in the electroforming (dielectric breakdown) of the aluminum oxide layer at the Al2O3/(PEDOT:PSS) interface.

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► Simple and cheap memories based on carbon nanotube – PEDOT:PSS composite are demonstrated.
► The rewritable memories operate at low voltages.
► The OFF to ON transition threshold voltage can be adjusted changing the nanotube concentration.