Enhanced resistive switching properties of HfAlOx/ZrO2- based RRAM devices

Resistive Random-Access Memory (RRAM) devices are recognized as potential candidates for next-generation memory devices, due to their smallest cell size, high write/erase speed, and endurance. Particularly, the resistive switching (RS) characteristics in oxide materials have offered new opportunities for developing CMOS-compatible high-density RRAM devices. In this study, the RS behavior of HfAlOx/ZrO2 thin films sandwiched structure between TiN bottom electrode and Au top electrodes were investigated. It was found that Au/HfAlOx/ZrO2/TiN stacks were superior in terms of RS performance when compare to Au/HfAlOx/TiN memory stacks. The devices demonstrated a good resistance ratio of high resistance state and low resistance state similar to 10(3) for Au/HfAlOx/TiN and similar to 10(5) for Au/HfAlOx/ZrO2/TiN stacks, respectively. Both stacks showed good retention characteristics (>10(4) s) and endurance (>10(3) cycles). The experimental current-voltage characteristics fitted with different conducting mechanisms, the linear lower bias region is dominated by ohmic conductivity, whereas the non-linear higher bias region was dominated by space-charge limited current conduction mechanism.

Automated summary

This study investigates the resistive switching behavior of HfAlOx/ZrO2 thin films. The Au/HfAlOx/ZrO2/TiN stack shows superior performance compared to the Au/HfAlOx/TiN memory stack. Both stacks demonstrate good retention and endurance characteristics.