Isothermal and CW laser crystallization of amorphous Ge2Sb2Te5 thin films

Transmission electron microscopy results are presented for as-deposited amorphous Ge2Sb2Te5 thin films after theirs isothermal annealing and CW laser illumination. Obtained microphotographs suggested that the crystallization process was driven solely by heterogeneous nucleation on the film boundary. The simplified model of steady-state crystallization process was developed for the case of heterogeneous nucleation mechanism. The values of nucleation rate and growth rate for isothermal and CW laser crystallization are calculated. The calculated values are in reasonable agreement with both our experimental data and with results previously published by the other authors.