Si_3.5Sb₂Te₃ Phase Change Material for Low-Power Phase Change Memory Application

Novel Si_3.5Sb₂Te₃ phase change material for phase change memory is prepared by sputtering of Si and Sb₂Te₃ alloy targets. Crystalline Si_3.5Sb₂Te₃ is a stable composite material consisting of amorphous Si and crystalline Sb₂Te₃, without separated Te phase. The thermally stable Si_3.5Sb₂Te₃ material has data retention ability (10 years at 412 K) better than that of the Ge₂Sb₂Te₅ material (10 years at 383 K). Phase change memory device based on Si_3.5Sb₂Te₃ is successfully fabricated, showing low power consumption. Up to 2.2×10⁷ cycles of endurance have been achieved with a resistance ratio lager than 300.