(Invited) Origin of conductive filaments and resistive switching in HfO2-based RRAMs

Summary form only given. Among the variety of technology options for the non-volatile memory devices, the resistive switching memory (RRAM) technology, which is based on reversible changes of the resistivity of a conductive filament formed in a dielectric film, is currently being seriously considered for its superior scaling and low power opportunities. While progress had been made in identifying key factors driving the resistive switching in metal oxides, there is no sufficiently developed microscopic description of the conductive filament features enabling memory operations. This presentation discusses how the nanoscale characteristics of the conductive filament, as determined by STM, C-AFM and TEM/EELS studies, impact resistive switching in the HfO2-based RRAM. Modeling the electron transport through the metal oxide film before the filament formation, as well as in high and low resistive states after the forming, allows the filament features responsible for the resistance changes to be extracted, which, in turn, provides insight into the key processes governing the switching.