The improvement of phase-change properties on Ge2Sb2Te5 using the superlattice-like structure

Ge2Sb2Te5 (GST)/Ge superlattice-like (SLL) films are investigated in the study. Reflection spectra measurements with polarized excitations and atomic force microscopy are carried out to investigate phase-change properties. Because of the Ge cladding films, GST phase-change properties could be improved. The thicker Ge cladding film is believed could lead to a relatively larger grain size. GST phase-change behaviors in the films can be adjusted by changing the layer thickness. We found the [GST(5 nm)/Ge(5 nm)]10 SLL film has the higher crystallization temperature, faster phase change speed, better thermal stability and relatively smooth surface. The GST/Ge SLL films may have the potential for commercial use.