(Invited) HfO2-Based RRAM for Embedded Nonvolatile Memory: From Materials Science to Integrated 1T1R RRAM Arrays

The Ti/HfO2/TiN-based system is a very promising candidate for Resistance change Random Access Memory (RRAM). By combining material science studies and integration in a Si CMOS technology, we succeeded to give quantitative insight in the resistive switching mechanism and to process a 4 kbit array with 1T1R RRAM devices. In particular, in-operando hard X-ray photoelectron spectroscopy allows to describe the resistive switching mechanism by a push-pull model of oxygen vacancies as a function of voltage polarity. Moreover, the characterization of integrated 600×600 nm2 TiN/Ti/HfO2/TiN 1T1R devices in the pulse-induced mode and the recent realization of a 4 kbit memory array have demonstrated promising performance for embedded non-volatile memory applications.