Thermal environment impact on HfOx RRAM operation: A nanoscale thermometry and modeling study
Matthew West, Georges Pavlidis, Robert Montgomery, Fabia Farlin Athena, Muhammad Jamil, Andrea Centrone, Samuel Graham, Eric Vogel
As the demand for computing applications capable of processing large datasets increases, there is a growing need for new in-memory computing technologies that avoid the von Neumann bottleneck. Oxide-based resistive random-access memory (RRAM) devices are a promising candidate for such applications because of their industry readiness, endurance, and switching ratio. These analog devices, however, suffer from poor linearity and from asymmetry in their analog resistance change. Various reports have found that the temperature in RRAM devices can increase locally by more than 1000 K during operation. Therefore, temperature control is of paramount importance for controlling their resistance. In this study, scanning thermal microscopy is used to map the temperature of Au/Ti/HfOx/Au devices at a steady power state and to measure temperature dynamics of the top electrode above the filament location during both resistive switching loops and analog pulsing. These measurements are used to calibrate the thermal parameters of a multiphysics finite elements model. The model is then used to understand the impact of the thermal conductivities and boundary conductances of the constituent materials on the resistance change during the first reset pulse in RRAM devices. It is found that the resistance change can be reduced significantly when the temperature in the titanium capping layer is reduced. We find that the greatest temperature reduction, and therefore, the lowest resistance change in the device is afforded by capping layers with increased thermal conductivities. This work links thermal properties to the resistance change in RRAM devices providing critical insights for engineering devices with improved linearity, repeatability, and symmetric analog behavior.
, Pavlidis, G.
, Montgomery, R.
, Farlin Athena, F.
, Jamil, M.
, Centrone, A.
, Graham, S.
and Vogel, E.
Thermal environment impact on HfOx RRAM operation: A nanoscale thermometry and modeling study, Journal of Applied Physics, [online], https://doi.org/10.1063/5.0145201, https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=935645
(Accessed September 23, 2023)