Sb-doped GeS2 as performance and reliability booster in Conductive Bridge RAM

In this work, for the first time at our knowledge, the improvement of chalcogenide-based CBRAM performance and reliability by Sb doping of the GeS₂ electrolyte is presented. An original analysis, based on in-depth physico-chemical characterization, device electrical measurements, empirical model and first principle calculations, is shown. We argue that optimized ~10% Sb doping in the GeS₂ electrolyte allows to achieve SET speed of 30ns at 2.2V (i.e. 0.66pJ SET programming power), while assuring 10 years data retention at 125°C, >10⁵ cycling and high robustness to Sn-Pb soldering profile. Finally, the improved thermal stability of the filament in the GeS₂-Sb matrix is clearly elucidated by means of molecular dynamics calculations.