Forming-free metal-oxide ReRAM by oxygen ion implantation process

We propose a new method for obtaining forming-free ReRAM devices by oxygen ion implantation (O 2 IIP) in the metal oxide film during the device fabrication process. By tuning the implantation dose, as-fabricated devices can be transformed into the ON state. Subsequent standard RESET and SET switching cycles reveal that the forming-free devices switch in a similar way to reference (formed) devices. The devices also show good R OFF /R ON ratio (>200), retention (10 4 sec@125°C) and endurance reliability (10 6 cycles), showing the absence of any device degradation caused by the O 2 IIP process. This method is applied on both (PVD) Ta 2 O 5 and (ALD) HfO 2 nanoscale ReRAM devices, demonstrating the versatile applications of the technique.