Memristors based on an organic monolayer of molecules and a thin film of solid electrolytes

The memristor is a fundamental circuit element (along with capacitor, resistor and inductor) whose conductance is dependent on the previous functioning history. The concept was postulated almost four decades ago and was actually fabricated only recently. We report the fabrication of memristive junctions using an insulating film of a monolayer of cadmium stearate deposited using the Langmuir-Blodgett method in the gap of an inert electrode and a chalcogenide solid electrolyte. The thickness of the organic monolayer is about 2.8nm and its presence helps ensure a constant gap size between the electrodes. We used an energetic plasma process to create the chalcogenide solid electrolyte using sulfur (S) containing plasma for converting thin films of copper (Cu) into a mix of covelite phase CuS and chalcocite phase Cu₂S.