Crystallization process of in situ annealed Ge2Sb2Te5 films

Electron-diffraction radial distribution function (RDF) was used as a structural probe to study the process of crystallization of Ge2Sb2Te5 (GST) films annealed in situ. The GST thin film began to crystallize after a characteristic peak of 0.52 nm appeared in the RDF, indicating the formation of third nearest neighbour ordering. The GST films preferentially form uniform nanosized grains. The similarities and differences in the structures of the amorphous phases and the polycrystalline phases are described.

► The in situ annealing experiments of GST films were done in series temperature.
► The GST films prefer to crystallize into uniform nanosized grains.
► The RDF reveals GST films crystallize after a 0.52 nm featured peak appeared.
► The structural similarities and differences between the two phases are described.