Phase change behaviors of Zn-doped Ge 2Sb 2Te 5 films

Abstract

Zn-doped Ge 2Sb 2Te 5 phase-change materials have been investigated for phase change memory applications. Zn 15.16(Ge 2Sb 2Te 5) 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 Ge 2Sb 2Te 5. The proper Zn atom added into Ge 2Sb 2Te 5 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. © 2012 American Institute of Physics.