Delayed-switch-on effect in metal-insulator-metal organic memories

We report a delayed-switch-on effect in organic memories; i.e., the organic memory devices can automatically switch from off state to on state after a certain period of time when biased at voltages below the threshold voltage. Meanwhile, the lower the voltage is, the longer the switching time will be. The time scales from milliseconds to about 104s with decreasing voltage. Moreover, by applying a certain voltage between threshold voltage and Vmax, intermediate states are also obtained. The existence of filamentary microconducting channels in the organic layer is proposed to be responsible for the observed switching phenomenon.