Phase change behaviors of Zn-doped Ge2Sb2Te5 films

Zn-doped Ge2Sb2Te5 phase-change materials have been investigated for phase change memory applications. Zn15.16(Ge2Sb2Te5)84.84 phase change film exhibits a higher crystallization temperature (∼258 °C), wider band gap (∼0.78 eV), better data retention of 10 years at 167.5 °C, higher crystalline resistance, and faster crystallization speed compared with the conventional Ge2Sb2Te5. The proper Zn atom added into Ge2Sb2Te5 serves as a center for suppression of the face-centered-cubic (fcc) phase to hexagonal close-packed (hcp) phase transition, and fcc phase has high thermal stability partially due to the bond recombination among Zn, Sb, and Te atoms.