Cr-doped Ge2Sb2Te5 phase change material, phase change memory unit and preparation method

The invention provides a Cr-doped Ge2Sb2Te5 phase change material, a phase change memory unit and a preparation method. The ingredient general formula of the Cr-doped Ge2Sb2Te5 phase change material is CrxGe2Sb2Te5, wherein x is an atomic ratio of the Cr element, and x is more than 0.5 and less than 1.5. Cr doping in Ge2Sb2Te5 is carried out, Cr is a kind of metal with an extremely high melting point, heat stability of a phase change material can be raised, Cr can form bonds with Ge, Sb and Te, so segregation is avoided effectively. Under action of external energy, the Cr-doped Ge2Sb2Te5 phase change material can achieve reversible conversion between high resistance state and low resistance state, and the resistance value ratio of the high resistance state to the low resistance state can reach about two orders of magnitudes. When the phase change material is employed as a memory media of a phase change memory, the phase change memory unit has advantages of fast phase change speed, low write operation current and the like, and high temperature data retentivity and reliability of the device are raised greatly. The phase change memory employing the phase change memory unit structure has advantages of high speed, low power consumption, good data retentivity and the like.