Thickness dependence of crystallization and melting kinetics of eutectic Sb70Te30 phase change recording film

As the thickness of eutectic Sb70Te30 phase change recording film was reduced, the crystallization temperature and activation energy for crystallization would increase, while the melting temperature and activation energy for melting would decrease. Accordingly, the archival stability and recording sensitivity can be improved. However, the recording speed for direct over write will be slowed down. Based upon the Johnson-Mehl-Avrami equation, it was found that the increase of film thickness would increase the nucleation rate of eutectic Sb70Te30 recording film and make the crystallization process become more nucleation-dominated.