Enhanced thermal stability and electrical behavior of Zn-doped Sb2Te films for phase change memory application

Abstract

Zn-doped Sb2Te films are proposed to present the feasibility for phase-change memory application. Zn atoms are found to significantly increase crystallization temperature of Znx(Sb2Te)1−x films and be almost linearly with the wide range of Zn-doping concentration from x = 0 to 29.67 at.%. Crystalline resistances are enhanced by Zn-doping, while keeping the large amorphous/crystalline resistance ratio almost constant at ∼105. Especially, the Zn26.07(Sb2Te)73.93 and Zn29.67(Sb2Te)70.33 films exhibit a larger resistance change, faster crystallization speed, and better thermal stability due to the formation of amorphous Zn-Sb and Zn-Te phases as well as uniform distribution of Sb2Te crystalline grains.