Excellent uniformity and multilevel operation in formation-free low power resistive switching memory using IrO _x/AlO _x/W cross-point

Excellent uniformity and multilevel operation in formation-free low-power resistive switching memory fabricated using the IrO _x /AlO _x/W crosspoint structure have been investigated. The thickness of the deposited films has been measured by high-resolution transmission electron microscopy with energy dispersive X-ray spectroscopy for each layer. The cross-point resistive switching memory devices have a tight distribution of SET/RESET voltages and low/high-resistance states as well as switching cycles. A high resistance ratio of >8 × 10 ² is obtained. This memory device shows excellent AC endurance of >5 × 10 ³ cycles, read endurance of >1 × 10 ⁵ cycles, and 10-year-data retention at 85 °C at a low power of 55 μW and low-current compliances of 50-200 μA. This study is not only important for cross-point memories but will also help in the design of high-density nanoscale nonvolatile memories in the future.