One-step phase transition and thermal stability improvement of Ge2Sb2Te5 films by erbium-doping

The crystallization behavior of Er-doped Ge2Sb2Te5 phase-change materials is investigated systemically for phase change memory application. It is observed that Er dopants can serve as a center for suppression of face-centered-cubic to hexagonal phase transition of Ge2Sb2Te5 films, leading to a one-step crystallization process. The crystallization temperature, 10-year data retention ability and crystalline resistance of Ge2Sb2Te5 films can be significantly increased. Raman spectra suggest that GeTe component is mainly responsible for the phase transition in Er-doped Ge2Sb2Te5 films.