On Some Unique Specificities of Ge‐Rich GeSbTe Phase‐Change Material Alloys for Nonvolatile Embedded‐Memory Applications
Minh Anh Luong, Marta Agati, Nicolas Ratel Ramond, J. Grisolia, Y. Le Friec, Daniel Benoit, A. Claverie
Abstract
Among the many possible phase‐change materials that can be used in digital memories, Ge‐rich GeSbTe (GGST) alloys are of special interest due to their much higher thermal stability, i.e., the higher crystallization temperature, they offer. However, in contrast to congruent materials which may transit from the amorphous to the crystalline state while keeping the same homogeneous chemical composition, GGST crystallization is obtained through the successive formation of the Ge and GST‐225 phases. For this reason, they show distinct properties and characteristics from those found in the canonical GST‐225 and GeTe alloys. Herein, some of these characteristics, their crystallization kinetics, the effect of N doping and oxidation, and their electrical properties are reviewed and highlighted.