A forming-free WOx resistive memory using a novel self-aligned field enhancement feature with excellent reliability and scalability

A thorough study of the switching mechanism for WO_X ReRAM gives clues about how to improve its performance and reliability. Consequently, a 60 nm WO_X ReRAM is achieved with excellent characteristics - 50ns fast switching, 10⁶ cycling endurance, large MLC window, low read disturb of >; 10⁹, and excellent 150°C/2,000Hrs data retention. Furthermore, the oxidation of the TiN barrier into an insulating TiNO_X causes the WO_X to protrude above the remaining TiN and thus creates field enhancement. The boosted electric field eliminates the need for an initial forming step.