Resistive Switching Properties of HfO2-based ReRAM with Implanted Si/Al Ions

The effects of Si and Al ion implantation on the resistive switching properties of a HfO2-based resistive random access memory (RRAM) device are investigated. Testing results demonstrate that Si or Al implantation into HfO2 films results in reduced electroforming voltages and improves reproducibility of resistive switching over 1,000 cycles as measured by a DC voltage sweeping method. Furthermore, the Si or Al implantation into HfO2 resistive switching memory devices was found to improve device yields, reduce operating voltages and their variability, expand on/off resistance ratio (>10(3) for Al-doped, > 500 for Si-doped), and increase retention times (> 3 x 10(5) s at room temperature). Doping by Si or Al ion is suggested to improve the formation of conducting filaments in HfO2 matrix and thus improve the performances of the Pt/Ti/HfO2/Pt device.