Role and optimization of thermal rapid annealing in Ta/TaOx/Ru based resistive switching memory

The performance of resistive switching (RS) device based on sandwich structure is greatly affected by the characteristics of the RS layer, electrode, and interface. In this work, the effect of rapid thermal annealing (RTA) (300 degrees C for 120 s) on the RS performance of Ta/TaOx/Ru device was investigated. The discrete distribution in high resistance state (HRS) and low resistance state (LRS) was suppressed after RTA. Meanwhile, the endurance in oxygen RTA is higher 104 times than that of vacuum RTA. The optimized oxygen RTA is contributed to change the microstructure of TaOx (amorphous to nanocrystal), providing the local conductive path, and implant oxygens in top electrode (TE) Ta, acting as an oxygen source (reservoir). It is shown that the nanocrystal TaOx and the oxygen content in TE are intrinsically crucial to the RS behavior and the simple low temperature oxygen RTA is a powerful technique to optimize the RS performance.