Resistive random access memories with nanodiamond dielectric films

We report the application of nanodiamond prepared by microwave plasma chemical deposition system as the dielectric film with copper as top electrodes and a tungsten counter electrode for the fabrication of resistive random access memory (RRAM). The RRAM is switched between the high-resistivity state and a low-resistivity state of nanodiamond film. The high or low resistance state can be probed by applying a low voltage across two counter electrodes on two sides of the nanodiamond film and measuring its conduction current. We observed that the Cu/Nanodiamond/W structure shows good performance with ON/OFF current ratio >10⁵ and retention time >10⁴ s. Nanodiamond is known to be chemically inert, good for heat dissipation, and has very low solid solubility in copper. It is, therefore, a suitable dielectric material for RRAM for harsh environments.