Understanding the Thermal Aspects in Dense RRAM Memory Arrays

Upcoming computing and market-ready storage technologies must not only become more powerful, but also more energy-efficient to meet future challenges. A promising solution are BEOL-integrated RRAM arrays. Research is ongoing to achieve ever higher device densities on ever smaller technology nodes. However, with shrinking feature size, thermal management is becoming increasingly important, especially with regard to temperature-accelerated switching.In this work, a 3D electrothermal model of an 8x8 RRAM array based on a 40 nm RRAM process is used to investigate the thermal effects on a selected device itself as well as on the adjacent RRAM cells. The study should help to better understand the thermal behavior in dense RRAM arrays especially for their integration in future scaled nodes. We show that thermal crosstalk can be avoided if the devices are placed far away from the shared bit line and the devices are separated by a heat blocking layer. Encapsulated heat also results in more energy-efficient switching.