Non-Linear I-V Characteristics of TiOy Film by Optimizing Thickness and Trap Density for Selector-Less ReRAM

The non-linear current voltage (I-V) characteristics in low-resistance state (LRS) of resistive random access memory is the most important device parameter for cross-point memory applications. An ultrathin TiO y tunnel barrier can significantly improve non-linear characteristics of resistive random access memory. Based on mathematical modeling, we verified that direct tunneling and trap assisted tunneling of TiO y layer are dominant in low voltage regime and high voltage regime, respectively. To maximize non-linearity, we need to reduce direct tunneling at low voltage by increasing film thickness and increase trap assisted tunneling at high voltage by increasing trap density.