Influence of interfaces on the crystallization characteristics of Ge2Sb2Te5

The crystallization times (τ x ) and crystallization temperatures (T x ) of the phase change material Ge 2 Sb 2 Te 5 (GST) as a function of capping materials was systemically evaluated. SiO 2 and GeO x capping materials accelerated the recrystallization of 10nm GST substantially and increased T x . In addition, the crystallization mechanisms depended on GST thickness as well as capping materials. For very thin films, T x increased by up to 120°C and re-crystallization times were shortened. Through optimization of phase-change layer thickness and interface conditions, a material system with faster recrystallization time and with higher thermal stability is proposed, which is promising for the scalability of phase change random access memory technology.