Multi-level switching of triple-layered TaOx RRAM with excellent reliability for storage class memory

A highly reliable RRAM with multi-level cell (MLC) characteristics were fabricated using a triple-layer structure (base layer/oxygen exchange layer/barrier layer) for the storage class memory applications. A reproducible multi-level switching behaviour was successfully observed, and simulated by the modulated Schottky barrier model. Morevoer, a new programming algorithm was developed for more reliable and uniform MLC operation. As a result, more than 10
⁷
cycles of switching endurance and 10 years of data retention at 85°C for all the 2 bit/cell operation were archieved.