A candidate Zr-doped Sb₂Te alloy for phase change memory application

Here, Zr-doped Sb₂Te alloy is proposed for phase change memory (PCM). Zr-doping enhances the crystallization temperature and thermal stability of Sb₂Te alloy effectively. Crystalline Zr₂(Sb₂Te)₉₈ film is manifested as a single phase without phase separation and the growth of crystal grain is dramatically suppressed. The density change of Zr₂(Sb₂Te)₉₈ material between amorphous and crystalline is ∼2.65 ± 0.03%, which is much smaller than that of Ge₂Sb₂Te₅ (6.5%). Phase change memory cells based on Zr₂(Sb₂Te)₉₈ material can be reversibly switched by applying 40-400 ns width voltage pulses, and the reset current is relatively small when comparing with the prototypical Ge₂Sb₂Sb₅ material. The resistance ON-OFF ratio of about 1.3 orders of magnitude is enough for figuring "0" and "1" out. Besides, endurance up to 4.1 × 10⁴ cycles makes Zr-doped Sb₂Te alloy a potential candidate for PCM.