[22p-A301-1~15] 16.1 Fundamental properties, evaluation, process and devices in disordered materials

▲ [22p-A301-1] [Young Scientist Presentation Award Speech] New Operating Principle: Contact Resistance Change Memory

〇Yi Shuang¹, Yuji Sutou^1,2 (1.Tohoku Univ. (AIMR), 2.Tohoku Univ, (Eng))

Keywords:Phase change material, Phase change memory, Contact resistance

Traditional phase change materials (PCMs) such as Ge₂Sb₂Te₅ (GST) can show as high as 10⁵ resistance reduction upon phase transition.Tthe amorphous and cubic-phase of GST exhibited p-type semiconducting behavior, while the hexagonal phase of GST was a degenerated a p-type semiconductor showing a metallic conduction behavior at room temperature. In a practical memory cell, to increase the storage density and enable the integration of the logic circuit, the memory cells are usually required to be scaled in ~nm order. In nm-sized cells, the contact resistance between PCM and metal electrode becomes a dominant resistance component in the whole cell. Consequently, the contact resistance significantly influences high read accuracy and heat efficiency of the nm-sized memory cell compared to the bulk PCMs themselves. In this study, we proposed a new phase change memory operating principle relying on the contact resistance change of a PCM.