An organic nonvolatile memory using space charge polarization of a gate dielectric

Abstract

We realize a nonvolatile and rewritable memory effect in an organic field-effect transistor (OFET) structure using polymethylmethacryrate (PMMA) dispersed with 10-methyl-9-phenylacridinium perchlorate (MPA^+ClO4^-) as a gate dielectric. Applying a voltage between a top source-drain electrode and a bottom gate electrode induces electrophoresis of two ions of MPA^+ and ClO_4^- -towards the corresponding electrodes in the memory devices. The drain currents of the memory devicesmarkedly increase from 10^<-9>A to 10^<-2>A under no gate voltage condition due to the strong space charge polarization effect. Our memory devices have excellent electrical bistability and retention characteristics, i.e. the memory on/off ratio reached 10^7 and the drain current maintained 40% of the initial value after 10^4s.