Dimensional Effect of Non-Polar Resistive Random Access Memory (RRAM) for Low-Power Memory Application

The relationships between the resistive cell dimension and the related analytical parameters such as the forming voltage, set voltage, and reset current were investigated to implement high-density and low-power unipolar RRAM. It was shown that the formation process in unipolar switching is strongly related to the cell dimension in the sub-nm region, not only in terms of its vertical thickness but also of its horizontal length, using the numerical simulation method. With the optimal cell size having sufficient initial resistance and a low forming voltage, the achievement of the greatest feasibility of the high-density low-power RRAM will be further accelerated. A numerical simulation was performed using a random circuit breaker (RCB) simulation model to investigate the optimal resistive switching condition. The on/off resistance ratio increases as the cell area decreases at the sub-nm level, and these phenomena are explained in terms of the relatively large set resistance change in a very small area due to the conductive defect (CD) amount effect in the RCB network model.