Unipolar resistive switching and retention of RTA-treated zinc oxide (ZnO) resistive RAM

This work investigates the effects of N₂ RTA treatment on characteristics of ZnO film as resistive RAM (RRAM). In addition, we also study the leakage current behavior and conducting mechanism in the low resistance state (LRS) and high resistance state (HRS) of ZnO RRAM. From the electrical characteristics, the resistance ratio (HRS/LRS) can be larger than 10¹¹, and the set and reset voltage is lower to around 0.3V and 2.2V, respectively. The RTA-treated ZnO RRAM reveals more improvement on the endurance up to 10³ times. Presumably, the RTA treatment will induce more crystalline phases in ZnO film and rearranges and/or recover the oxygen vacancies and distribution in the film, and it is beneficial for the resistance switching. Low power and high resistance ratio (HRS/LRS) of ZnO RRAM can be finished for the RTA-treated ZnO RRAM with inexpensive Al metal electrode.