Thermometry Across Switching Oxide Layer in ReRAM Device

Resistive random access memory (ReRAM) is an emerging non-volatile memory (NVM) technology candidate, having the ability to address the next-generation data storage demand. Even though localized self-heating factors impact the functioning of ReRAM, thorough investigations are limited due to nanoscale geometry constraints. This study employs thermometry across the oxide layer to monitor the generation and distribution of local temperature in both SET and RESET states. A maximum local temperature (Tmax) of 690 K at the filament center is estimated during the low resistive SET state, with a complete cylindrical filament of diameter 0.5 nm upon an applied voltage (Va) of 0.55 V at the top electrode (TE). A transient heat transfer model achieves the current heating time on a nanosecond scale (~ 1 ns). Similarly, during the RESET state with Va = 0.1 V, a gap of 5 nm is considered at the bottom electrode (BE) interface, where a Tmax of 400 K is obtained at the filament tip near BE. The radial temperature distribution is evaluated from the filament to surrounding oxide, where 52.93% and 23.44% local temperature declination are detected at the filament-oxide junction during SET and RESET states, respectively, where the local temperature further declines to room temperature at device walls. Additionally, the local temperature concerning Va is calculated across the positive and negative voltage sweep from an analytical simulation, where the device variables and model parameters have collaborated with an experimental I-V characteristic from a fabricated ReRAM device.