Relationship between nature of metal-oxide contacts and resistive switching properties of copper oxide thin film based devices

• Growth condition optimization of phase pure copper oxide thin film for memory devices.
• Electronic, structural and optical characterization of Cu2O and CuO thin films.
• Effect of top electrode on resistive memory characteristics of MOM devices.
• Ohmic contact is essential for observing resistive switching in copper oxide devices.

The current-voltage and resistive switching properties of Cu2O and CuO based resistive random access memories in metal-oxide-metal structure with Cu as bottom electrode and different metals (Ti, Ag, Au and Pd) as top electrodes have been investigated. The observation of resistive switching in Cu2O and its absence in CuO based devices indicates that Ohmic nature of top and bottom metal–oxide contacts is favourable for resistive switching behaviour. The rectifying metal-oxide contact results in the applied voltage drop at the rectifying contact, resulting in the absence of electric field induced structural changes which are crucial for occurrence of resistive switching. The values of switching parameters, such as, electroforming, reset, set voltages and also the resistance ratio are also observed to depend upon the work function of the electrode materials and nature of metal-oxide interface.