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 (C60) semiconductor and an electron-trapping polymer, poly(perfluoroalkenyl vinyl ether) (CYTOP). The transistors with a Si++/SiO2/CYTOP/C60/Al structure show good n-type transistor performance with a threshold voltage (Vth) of 2.8 V and an electron mobility of 0.4 cm2 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 (ΔVth) of 10 V. A memory on/off ratio of 105 at a small reading voltage below 5 V and a retention time greater than 105 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 C60, the switching voltages of our memory transistors become significantly lower than those of conventional memory transistors based on pentacene.

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► We report organic n-type nonvolatile memory transistors based on a fullerene semiconductor.
► The memory transistor can be programmed/erased by applying gate voltage pulses of 50/−45 V.
► The memory transistor shows a memory window 10 V and a retention time over 105 s.
► The memory effect originates from trapping and detrapping electrons at a CYTOP/SiO2 interface.