The study of crystallization process of as-deposited amorphous phase change-materials by in situ annealing experiments

Abstract

The crystallization process of two types of phase change materials (Ge2Sb2Te5 and AgInSbTe) has been studied by in-situ annealing experiments in the column of a transmission electron microscope. Under the same heating rate (7.5KIs), the Ge2Sb2Te5 material starts to nucleate at 170 °C, while AgInSbTe starts to nucleate at 250 °C. The measured nucleation rate of Ge2Sb2Te5 is 8.2x10'4cm3s1 larger than nucleation rate of AgInSbTe (3.5x1014cm3s').By studying the partially crystallized samples, we found that homogeneous nucleation is dominant for both Ge2Sb2Te5 and AgInSbTe with ZnS-Si02 as the dielectric layer in the thinned samples.