Phase-Change Characteristics and Crystal Structure in Multi Stacked GeTe/InTe Films

Abstract

The changes in the microstructural and electrical properties of multi stacked GeTe/InTe layers were investigated. When the GeTe layer was thicker than the InTe layer, a Ge(In)Te phase occurred only after annealing. Although crystallization should originate from the GeTe layers, there was a uniform distribution of Ge and In atoms in the Ge(In)Te phase after 400 °C annealing. The dropping temperature of sheet resistance was slightly increased with a decrease in GeTe thickness. If the GeTe layer was thinner than the InTe layer, the phases observed after annealing were not only the Ge(In)Te phase, but also the In7Te10 phase. The formation of the In7Te10 phase was the primary cause of the increasing sheet resistance after crystallization by subsequent annealing.