Dielectric properties of (multilevel) switching devices based on ultrathin organic films

Dielectric properties of an organic material, which shows conductance switching with associated memory phenomenon, have been studied. The devices have been modeled as a parallel combination of a resistor and a capacitor. During conductance switching, devices’ resistive and capacitive properties have been found to change. Multilevel conductivity, which is due to different density of high-conducting reduced molecules in the devices, has also been manifested in dielectric measurements. We could induce (‘write’) a low-conducting state and three high-conducting states and probe (‘read’) them by measuring frequency dependence impedance characteristics without any dc bias for multilevel read-only and random access memory applications.