Electronic memory effects in a sexithiophene - poly(ethylene oxide) block copolymer doped with NaCl. combined diode and resistive switching behavior

Electrical transport in devices consisting of an electrode of a conducting polymer (poly(ethylenedioxythiophene):poly(styrenesulfonate), PEDOT:PSS); a layer of a sexithiophene-poly(ethylene oxide) (6T-PEO) block copolymer with an Al top electrode is investigated. These devices show diode behavior with the larger current density flowing when the PEDOT:PSS electrode is biased positive with respect to the Al electrode (forward bias). Introduction of inorganic salt (NaCl) in the PEDOT layer results in resistive switching behavior under forward bias while retaining the diode character. The switching allows for storage of information and rewritable memory operation is demonstrated for the diodes although the retention time of the information is still very short (~10 s). The reported combination of switching and diode behavior is an important requirement for passive matrix addressing of resistive switching memory cells in an array and shows that materials with combined ion and charge transport properties are interesting for information storage.