We examined the crystallization behavior of Ge2 Sb2 Te5 in different amorphous states in the context of the kinetic approach using a laser heating method. We measured the changes in reflectance values after varying the applied laser pulse power and duration time and estimated the fraction of the crystalline phase of Ge2 Sb2 Te5 with a nanosecond time scale. The modification of the laser pulse sequence allowed a comparison between the crystallization behaviors of the as-deposited and melt-quenched amorphous states. We determined crystallization kinetics, such as nucleation and growth mechanisms, by combining the results from reflectance measurements and transmission electron microscopy. We observed the different crystallization behaviors between the as-deposited and melt-quenched Ge2 Sb2 Te5 films. The melt-quenched Ge2 Sb2 Te5 demonstrated fast crystallization with a short incubation time compared to the as-deposited sample. The melt-quenched Ge2 Sb2 Te5 also crystallized with a number of fine grains in contrast with the few larger grains seen in the as-deposited Ge2 Sb2 Te5.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Renewable Energy, Sustainability and the Environment
- Surfaces, Coatings and Films
- Materials Chemistry