The crystallization of Cu-doped Ge2Sb2Te5

Cu-doped Ge2Sb2Te5 was prepared on Si (100) wafer by pulse laser deposition. The crystallization behavior of amorphous sample was investigated through resistance-temperature measurement and X-ray diffraction (XRD). The result of resistance-temperature measurement shows that the crystallization temperature (T-c) of Cu-doped Ge2Sb2Te5 increases with increasing Cu doping content, which is beneficial to improve the stability of phase change film. The XRD patterns of Cu-doped sample contain unidentified extra crystalline phases, while the original crystalline phase remains unchanged. It reveals that Cu does not easily incorporate into the fcc and hex structure of GST, but tends to segregate and produces new compounds. And these new compounds could be responsible for the increasing of the crystallization temperature.