Effects of barrier layers on the electrical behaviors of phase-change memory devices using Sb-rich Ge-Sb-Te films

Abstract

To improve the memory characteristics of the device using Sb-rich Ge-Sb-Te alloys, especially the data endurance under repetitive rewriting cycles, a nm-thick Al2O3 was proposed as a barrier layer, because the inter-diffusion between top electrode contact (W) and phase-change material had been observed. It was confirmed that the memory device using a 4-nm-thick Al2O3 layer showed good programming behaviors and improved data endurance, compared with those of the device without any barrier layer and with a TiN.