Organic heterostructure device with nonvolatile memory behavior using electrically doped layers

Abstract

Recently, several memory devices based on organic semiconductors were reported. In most cases, single organic layers were employed, and the switching mechanisms were not fully understood. Here, we report on a novel device structure based on electrically doped organic heterostructures showing highly stable memory behavior. The organic layers are embedded between a bottom indium tin oxide and a top metal contact and form a quantum well-like structure. The device shows a hysteresis in the current-voltage characteristics and well-defined switching behavior. We achieved reproducible bistable electrical switching and stable memory phenomena in these organic multilayer heterostructure devices. The two states were retained for up to several days without noticeable decrease of their on/off ratio. Further, it was found that the ratio of the on/off current depends on the writing voltage, allowing the use as multistate memory.