Effect of Structural Change on Thermoelectric Properties of the Chalcogenide Ge 2 Sb 2 Te 5 Thin Films

Abstract

Ge2Sb2Te5 (GST) films grown onto SiO2 (250 nm)/Si substrate at room temperature were annealed at various temperatures to investigate the structural variations. The GST films changed from amorphous to face-centered cubic (FCC) and hexagonal closed packed (HCP) crystalline phases as the annealing temperature increases and the samples annealed at 380 degrees C showed co-existence of the FCC and the HCP. Samples annealed at 380 degrees C showed the highest charge carrier concentration, the lowest resistivity, and the highest power factor. (C) The Author(s) 2014. Published by ECS. All rights reserved.