The Si2Sb2Te5 phase change material has been studied by applying a nano-tip（30 nm in diameter） on an atomic force microscopy system.Memory switching from a high resistance state to a low resistance state has been achieved,with a resistance change of about 1000 times.In a typical I-V curve,the current increases significantly after the voltage exceeds～4.3 V.The phase transformation of a Si2Sb2Te5 film was studied in situ by means of in situ X-ray diffraction and temperature dependent resistance measurements.The thermal stability of Si2Sb2Te5 and Ge2Sb2Te5 was characterized and compared as well.
