Mechanism of oxidation on Si₂Sb₂Te₅ phase change material and its application

Uniformly oxygen doping into phase change materials (PCMs) will increase their crystallization temperatures, but natural oxidation of PCMs has an opposite effect. Mechanism of oxidation for Si₂Sb₂Te ₅ was studied by in situ X-ray photoelectron spectroscopy, employing an oxygen content gradient sample. During an oxidation process, oxygen preferentially reacts with Si due to its smallest electronegativity value among Si, Sb, and Te elements. Models have been proposed for the different mechanisms of oxidation. O-doping into Si-Sb-Te was proposed to prepare nano-crystal PCM based on the discovering. Performance of nano-crystal material and memory device was effectively promoted.