Discussion on the Mechanism of Reversible Phase Change Optical Recording

Abstract

In stoichiometric GeTe-Sb₂Te₃ films, reversible phase change optical recording materials, Sb addition is used widely in order to improve the crystallization speed, the data retention time and the stability of cyclic operation, but its mechanism is not clear. V-VI compounds (GeTe, SnTe) are well known as compounds in which the ferroelectric structural phase transition occurs. The dielectric constant ε₀ changes largely due to a change in the short-range order of weakly bound nearest neighbors in the crystal to more strongly bound nearest neighbors in the amorphous phase. Therefore, it is necessary to discuss the effect of Sb addition in the stoichiometric GeTe-Sb₂Te₃ composition upon the thermal stabilities, the dynamic properties of crystallization and the dielectric constant change Δε₀ based on the amorphous-to-crystalline phase transition.