Organic nonvolatile memory transistors based on fullerene and an electron-trapping polymer

We report for the first time organic n-type nonvolatile memory transistors based on a fullerene (C-60) semiconductor and an electron-trapping polymer. poly(perfluoroalkenyl vinyl ether) (CYTOP). The transistors with a Si++/SiO2/CYTOP/C-60/Al structure show good n-type transistor performance with a threshold voltage (V-th) of 2.8 V and an electron mobility of 0.4 cm(2) V-1 s(-1). Applying gate voltages of 50 or -45 V for about 0.1 s to the devices induces the reversible shifts in their transfer characteristics, which results in a large memory window (Delta V-th) of 10 V. A memory on/off ratio of 10(5) at a small reading voltage below 5 V and a retention time greater than 10(5) s are achieved. The memory effect in the transistor is ascribed to electrons trapped at the CYTOP/SiO2 interface. Because of the use of high-electron-mobility C-60, the switching voltages of our memory transistors become significantly lower than those of conventional memory transistors based on pentacene. (C) 2012 Elsevier B.V. All rights reserved.