Exploring the applicability of amorphous films of system In-Sb-Te as phase change materials

Abstract

Hereby, we present In-Sb-Te amorphous films grown by pulsed laser deposition technique using, as targets, crystalline ingots (with corresponding stoichiometry) prepared by traditional melt-quenching method. The explored nominal compositions were In50Sb15Te35, about a ternary compound formed in the quasi-binary InTe-SbTe system, metastable at room temperature, and two eutectics In8Sb8Te84 and In10Sb51Te39. Measurements of electrical sheet resistance evidenced that the amorphous films behave as electrical insulators at room temperature and present a giant jump in resistivity towards a conducting state on crystallization. Differential scanning calorimetry technique complemented the structural information obtained by X-ray diffraction and revealed temperatures of crystallization of the amorphous films as well as their melting points. Due to their temperature characteristics (crystallization temperature≈225°C and melting temperature≈540°C), In10Sb51Te39 film results very attractive from technological point of view. These characteristics could make this eutectic composition a good candidate for using in phase-change memory devices.